CFD Simulation
Professional Computational Fluid Dynamics (CFD) Simulation
CFD simulation is at the core of what we do here at our Singapore office in BroadTech Engineering.
We are a CFD company which provide a comprehensive range of CFD consulting services such as CFD flow analysis, CFD Modeling, Mechanical simulation and Digital Prototyping solution to help design engineers and Analysts make the correct engineering decisions earlier in the design development process.
This CFD consulting allows engineering companies to leverage the CFD services to validate and optimize designs way before the manufacturing phase and increases the performance efficiency.
What is CFD
CFD or computational fluid dynamics is the study of the Fluid flow of liquids and gases in and around specifically engineered objects under study. It also involves the numerical modeling and simulation of thermal behaviors.
The equations governing fluid dynamics is complex and is often unsolvable manually by hand.
However, through the use of CFD simulation software methods and Computational Fluid Analysis algorithms, it has made it possible to accurately predict the Fluid flow behavior of liquid and gases and its interaction with the engineering product designed.
Why CFD Simulation
Computational fluid dynamics or CFD analysis is an important part of the engineering design process as it helps to boost the energy efficiency of design performance, reduce the risk of failure and helps to accelerate innovation in engineering design.
By having insights into the forces that affect the fluid dynamics simulation through the use of Fluid Dynamic Analysis, you can make the critical design decisions that can significantly reduce energy consumption and improve performance efficiency
Featured CFD Simulation Case Studies
Optimization of Thermal Cooling Systems
One of the key processes in a metal extrusion plant is the efficient thermal cooling of the extruded beams through natural convection. Our customer needed to achieve maximize the airflow while minimizing the acoustic noise footprint outside the factory. The current air intake designs were modified and optimized using Airflow Simulation to guarantee uniform airflow, sound vibrational isolation and maximum cooling capacity of interior currents. Buoyant structures and wind sensitivity were analyzed using Air Flow Analysis to evaluate different designs of air intakes.
Thermal Comfort of Glass Facade
An in-depth thermal comfort analysis was conducted in the intermediate space of the condominium building.This space is isolated from the exterior by means of a glazed facade. Right from the beginning, It was imperative to address the greenhouse effect and the influence of interior flow currents created by wind. All must be within acceptable comfort ranges. CFD results were combined with energy simulation in order to set-up the most energy-efficient facility.
Features & Benefits of CFD Simulation
1. Less Reliance on Physical Prototyping
Through our CFD engineering simulation capabilities, we are able to help our clients in the capacity of a CFD Services Company to accurately predict the real-world performance of their various engineering design iterations.
This helps to minimize reliance on the need to fabricate and test multiple physical prototypes variants, thus helping companies to save a tremendous amount of development time and money.
2. Cutting Engineering Development Time
CFD Fluid Flow simulation enables engineering teams the flexibility to simultaneously test design performance in multiple conditions and failure scenarios.
This helps to significantly cut down on the engineering development time and save money and resources which would otherwise be spent on testing
3. Focus on Design, We Take the Complexity out of Engineering Simulation
We help you to channel your focus on designing the product for optimum performance by taking care for you the complexity of advanced Computational Fluid Dynamics Simulation analysis and Numerical modeling methods
4. Early Validation of Engineering Design
Through the running of CFD Fluid Flow Analysis simulation during the engineering design process design issues such as miscalculations in judgment, can be identified and solved before they turn into serious problems, such as
- Using Wind Load Analysis to predict Building collapse due to Structural failure when subjected to wind loads
- Thermal Overheating of electronic components
- Failure of automotive car parts
The consequence of such failures can be serious and Financially Expensive, such as Complete product recall from the market, legal lawsuits or even loss of Precious life.
Early Identification & Highlighting of Design Errors
An accurate CFD simulation performed by a Professional CFD Consulting Company also helps to identify and highlight any occurrence of engineering design errors early in the engineering design process where the product cost is not yet locked in and allows for more flexibility for design modifications to be implemented.
5. Multiphysics Simulation
We also have the professional CFD software tools and capabilities to perform Multiphysics simulation to conduct detailed analysis of Fluid flow phenomena such as
- Heat Transfer behavior to study Thermal characteristic of Specific Designs
- Fluid flow simulations to study accurate and detailed fluid flow behavior
- Using advanced computational fluid flow simulation tools, we as an Experienced CFD Fluid Dynamics Company can accurately simulate fluid flow behaviors and patterns in various situation, such as Laminar and Turbulent flow Modeling.
- Modeling of AirFlow of incompressible fluids moving around a physical object (such as Aeroplane wing airfoil Simulation)
- Cavitation CFD, where it involves the study of the Formation of Hollow cavitation in Fluid
- Fluid Flow simulation which takes into account the simultaneous effects of fluid thermal behaviors, such as natural convection buoyancy and forced convection flows
- Simulation of mold flow during Plastic injection molding process
Overview
About Us
BroadTech Engineering is a Leading Engineering Simulation and Numerical Modelling Consultancy in Singapore.
We Help Our Clients Gain Valuable Insights to Optimize and Improve Product Performance, Reliability, and Efficiency.
We Help Our Clients Gain Valuable Insights to Optimize and Improve Product Performance, Reliability, and Efficiency.
Questions?
Contact Us!
Please fill out the form below. Our friendly customer service staff will get back to you as soon as we can.
1. Powerful ANSYS FEA Simulation Software Tools
2. FEA Consultants with Extensive Research & Professional Experience
3. FEA projects Completed in a Timely and Cost-effective Manner
4. Proven Track Record
5. Affordable
6. Full Knowledge Transfer
Applications of CFD Simulation
CFD analysis should be used throughout the design process to gain insight and to make good design decisions
1. Thermal prototyping
CFD Thermal analysis can be used to solve and optimize engineering design thermal performance for all modes of heat transfer (ie. Conduction, Convection, Radiation) between various medium (eg. From Solid to solid, Solid to fluid, or Fluid to Fluid)
eg. Temperature behavior in an electronics enclosure
2. Building Efficiency Design
Use CFD software and thermal modeling tools by ESD Consultants for various architectural and MEP Building Performance Simulation applications, such as
- Optimization of building CFD aerodynamics using Wind Simulation for minimization of Wind loads
- Wind engineering and Natural Ventilation CFD Analysis for Enhancing natural indoor ventilation and reduces reliance on Mechanical forced ventilation by Fans
- Fluid Flow Optimization of the Building Mechanical, Electrical and Plumbing systems to Improve Energy efficiency
- Data Center CFD Simulation and HVAC CFD Simulation to enhance HVAC system efficiency and lower Energy consumption
- Thermal Comfort Analysis – Use of Thermal Simulation visualization technology and Natural Ventilation Simulation approach to Ensuring the comfortable indoor environment in a crowded building indoor environment (eg. Meeting hall)
- Wind Driven Rain Simulation to simulate the entry of rain into building interior due to various Wind directions
3. Fluid Flow Control in Industrial Applications
CFD Heat Transfer Simulation can be used for Optimization of Engineering designs when you need to improve performance such as
- Drop in pressure as fluid flows through a valley component
- Design performance behavior in Turbulent flow conditions/scenarios using Turbulent Simulation
- Distribution of Fluid flow and Thermal temperature flow. eg. Efficient use of optimized heat sinks to eliminate the need for cooling fans in electronics. This helps to provide a significantly smaller design form factor and increases product performance reliability.
- Hydrodynamic Simulation Modeling of Ship Hull Design for performance of Ship Trim optimization
- Optimize Efficiency of Turbo-machinery and Combustion Engines
- Solving of in-flight icing by the CFD Engineer.
4. Automotive Aerodynamics
Aerodynamic simulation through the use of CFD Modeling
eg. Study of wind resistance effects on a car, motorcycle in motion
Types of CFD Simulation Scenarios
Incompressible Flow
In a majority of engineering applications, the Fluid flow involved in the CFD Design Study is incompressible and turbulent, where the flow speed is below Mach 0.3. In such simulation applications, an Advanced solver is needed.
Application Example of such simulation includes
- Commercial Ship Hydrodynamics simulation for purpose of Ship Optimization
- Green Water Loading Simulation to Validate Design of Ship Deck Structure and FPSO
Compressible Flow
A Compressible fluid flow is where the fluid density varies with the Pressure values. Such Fluid flows are usually high speed flows with Mach numbers greater than 0.3
Examples include Aerodynamic applications such as optimization of Fluid flow over an airplane wing aerofoil and applications in industrial processes such as engineering of Fluid flow through high-performance grade valves
The CFD simulation analysis of compressible flow takes into account the formation of shocks.
In the case of liquid, it comes in the form of water hammers.
Cavitation
Cavitation is a physical phenomenon that occurs in many high-velocity liquid flows. It occurs when vapor bubbles are formed when the liquid pressure drops below the vapor pressure of the liquid.
Prolonged cavitation have a negative effect of causing pitting and erosion in equipment, resulting in significant reduction in efficiency, costly downtime and repairs
Cavitation is common occurrence in devices, such as
- High-performance valves
- Flow control valves devices
- Fluid flow simulation of Pumps using Mechanical Fan CFD Simulation, such as Axial fans CFD Modeling, Jet Fan CFD Simulation, and Centrifugal Fan CFD
- Industrial mixing Propeller CFD Simulation
- High speed Centrifugal Pump – Cavitation is simulated using Centrifugal Pump CFD Simulation
Using CFD Cavitation simulation, we are able to efficiently and quickly analyzed
- Predicts the Occurrence and location of bubble formation within the flow
- Monitor the vapor bubble to volume ratio
Scalar Mixing of 2 Fluids
We can also simulate the scalar mixing of two similar fluids and accurately track the variation of fluid properties, such as changes in overall density or viscosity of the fluid mixture as the scalar is added.
Using the free surface modeling capability, we are able to dynamically simulate the interface between liquids and solids
This is used for the CFD Modeling and Study of flow phenomena in a wide range of engineering applications
- Industrial applications, such as Stir Tank Propeller Simulation used in Mixing processes
- Building Architectural applications, such as using Air Dispersion modelling for Tracking the distribution of air pollutants in smoke. Such Air Quality Modeling studies uses specialized Air Pollution Dispersion Model, such as Aermod.
- Infrastructure design, such as naturally occurring flows behavior like waves sloshing and fluid spilling
Call Us for a Free Consultation
Discover what CFD Simulation can do for your company today by calling us at +6581822236 for a no obligation discussion of your needs.
If you have any questions or queries, our knowledgeable and friendly consultants will be happy to answer any of your queries and understand more about your needs and requirements
Alternatively, for quote request, simply email us your technical specifications & requirements to info@broadtechengineering.com
Other Featured CFD Simulation Case Studies
CFD Simulation of Smoke extraction system of Mall Under different fire scenarios
Simulation Objective:
The objective of this CFD Simulation is to investigate the effectiveness of the smoke extraction system of the Meraas Outlet Village mall under two different fire scenarios.
Methodology/Approach
Fluid domain is created in the Ventilation CFD Analysis base on the information from the given architectural and MEP drawings from the client, this shopping mall is located at Dubai (UAE) and has an approximate surface area of 6,600.00 m2, with and an average height of 13.5 m. The structure has seven main entrances, three of them automatics and the rest manuals, during the fire scenario, it is considered that all the doors will be open.
A hybrid mesh of tetrahedrons and hexahedrons with 8.1 million of cells, is created in the CFD ventilation analysis of the shopping mall. Finally, a grid adaptation was employed to concentrate grids in the regions of high velocity and temperature gradients.
Transient continuity, momentum, turbulence kinetic energy, turbulence energy dissipation rate, as well as the species transport equations to model the propagation of the smoke. The flow in the CFD Flow Analysis is assumed to be incompressible using the hypothesis of Boussinesq to consider the buoyancy effects.
Standard k-ε turbulence model
The standard k-ε turbulence model was used in the analysis. The coupling between the pressure and velocity fields has been done with the coupled algorithm. Finally, the second-order of precision has been applied in both temporal and spatial discretization.
The fire has been modeled in the CFD Flow Simulation as a heat source and a smoke source generated as a combustion product. Using t²-fire laws is the most common way to simulate the evolution of the heat release rate (HRR) during both the growth and decay stages of the fire. In shopping centers, the fire has a growth speed which is considered ultra-fast, i.e., the fire needs only 75 seconds to reach the maximum power of 5 MW, and the simulation is carried out for 30 min.
0 < t < 75 sec grow periods
75 < t < 900 sec Maximum fire periods for 15 min
900 < t < 1050 sec decay period
1050 < t < 1800 sec, to check the performance of the smoke extraction system
Outcome & Conclusion
In summary, base on the Flow Simulation results obtained from the CFD Modeling services provided to the client, we know that under a fire scenario of 5 MW which is off after 17.5 minutes (1050 sec), the extraction system guarantees that no more than three compartments of the mall (atrium or corridor) will be affected by the smoke. In the worst case, in two compartments the smoke layer reaches the breathing height (1.5 m). However, once the fire is off, from the CFD Simulation results it is noted that the system needs 3.5 minutes to clear such breathing height and 8 minutes to evacuate the smoke until the extraction height.
Wind Driven Rain (WDR) CFD simulation project for environmental flows around an aircraft hangar
Objective
The objective of the CFD project was to investigate the environmental flow impact of the aircraft hangar and its orientation through the use of Wind Driven Rain (WDR) Simulation.
Our CFD Consultant was responsible for grid generation task with Pointwise software and simulation setup in ANSYS Fluent Software, in collaboration with the local Engineering Services companies.
Outcome
The outcome of the CFD simulation and Wind Driven Rain Louvre Design project was to advise the client on the flow impact of each possible orientation of aircraft hangar setup together with a report prepared by my supervisor.
HVAC CFD Simulation study of a Sport Arena
We were engaged as a HVAC CFD Consultancy to perform the redesigning project of the “Kaposvar sport arena”
The whole ventilation and air conditioning system was replaced.
Objective:
The main objective of the HAVC simulation was to achieve an accurate temperature distribution in the arena which satisfies the industrial standards for sports arenas. The input for the CFD simulation: like the position of the ventilation inlets and outlets, seats of the spectators (they were modeled as heat sources), the position of the lamps (likewise were taken into account as heat sources) and the full 3D CAD geometry of the arena was provided by the customer.
We ran a steady case buoyant HVAC CFD simulation for the winter and for the summer conditions too (the temperature of the air inlets and the temperature of the walls were different in the 2 cases).
Outcome Results
The HVAC CFD Analysis results revealed that the temperature distributions were not satisfied with the original arrangement of the air inlets and outlets. We suggested our customers swap the air inlets and outlets above the largest tribune. He approved my proposal and asked me to do 2 more runs with the modified arrangement.
The CFD Simulation calculations proved that with the modified arrangement the temperature distributions comply with the industrial standards. Finally, the HAVC design was modified and the sporting arena was equipped with the modified and optimized arrangement.
Integrated Environmental modeller (for HDB)
Objective:
Wind flow simulations of Singapore island coupled with solar and acoustic data for comfort level optimization of HDB estates
Approach:
FVM for CFD with OpenFOAM with data from a ray tracer for solar incidence and acoustic data coupled by pressure
Outcome:
A web-based micro-service deployed on HDB cluster for the Wind Flow Analysis simulations to different precinct geometries. Functioned as the CFD Software lead and as well as application specialist.
Software won several government awards, including the President’s award for merit in R & D
Urban Airflow Dynamics Simulation over the Bolund hill
Our CFD Consultant also worked on the flow over the Bolund hill, a hill located on a peninsula close to the city of Roskilde in Denmark. Its shape represents a scaled down model of a typical wind farm site, hence accurately simulating the flow over it is of great importance to the wind energy industry. WMLES (similar setup to case 1) as well as RANS models (namely the k-ε model, commonly used in atmospheric flows) were used on this case study, both of which performed very well.
Nevertheless, it was noted that uncertainties in the hill geometry used in the numerical CFD simulations (due to interpolation errors following the triangulation of the field data) could have a rather large effect on the quality of the CFD simulation results.
Numerical study of free surface flow based on smoothed particle hydrodynamics (SPH) method
Objective:
The objective of this CFD Consulting Client research is to develop a meshfree CFD solver similar to that used in Ship Hydrodynamics Simulation
Methodology
This is to be adapted for the flows with free surface especially large deformation of free surface. A parallel, multi-phase SPH code for numerical CFD simulation of flow field is developed using FORTRAN. An improved boundary treatment approach based on coupled boundary approach is proposed so that the pressure of boundary particles is more accurate and the CFD simulation results of flow field using the improved approach are better than that of the original approach.
A non-reflection boundary treatment approach is proposed for this Multiphysics Simulation. The SPH code is adopted for the CFD Simulation to investigate the water entry of a solid body. The parallelized one-phase and two-phase SPH code are adopted to simulate the whole process of a wedge entering water respectively.
Outcome & Conclusion
Similar to Numerical Ship Hydrodynamics Studies, the comparison of the numerical results of one-phase code and two-phase code is analyzed.
Finally, the computational Fluid flow Simulation results of two-phase code are verified by our experimental data.
The different type of validation cases show that the developed SPH code are quite robust and suitable for the CFD simulation of the flow field with interface or free surface.
Sloshing: Oil tank Hydrodynamic CFD simulation & Optimization
Objective:
The main purpose of the Multiphysics Modeling study was to optimize the design of the oil tank, as well as the design and location of the baffles located inside the oil tank of the FSAE race car. It was to ensure that when the car underwent longitudinal and lateral load, sloshing was minimized, such that there was oil at the pickup point, which is located at the bottom of the oil tank, at all times, so that oil distribution to the engine is not disrupted at any point during the race.
Methodology:
As for the CFD design of the overall oil tank, a few designs were considered, some of which included a basic cylinder shape, which was used in previous iterations of the race car, as well as a cylinder attached to a circular cone with different cone angles. All oil tank designs have similar volume, as well as similar inner diameter due to the availability of materials in the workshop. Designs for baffles included circular plates with different configurations of cut holes, and to be mounted at different points in the oil tank.
Multiphase Flow Simulations were done using Autodesk CFD and ANSYS Workbench Fluent, with transient solvers being used in this study. Acceleration data entered in the solvers was collected from telemetry data from the race car. Oil control volume inside the oil tank CFD simulation was set to be the same for all cases. As for ANSYS CFD Software, an additional step to autosave the images was needed.
Outcome & Conclusion
Based on the sets of images gathered from the CFD Consulting study, it was concluded that the new design which include a cone at the bottom of the oil tank, as well as circular baffles located inside the tank was seen to minimize the oil sloshing around while the car was moving.
Long-term Ecological, water and Sediment quality monitoring and Numerical Modelling of the seawaters around Singapore
This Water treatment Simulation project is part of PUB seawater environment impact assessment program.
Objective:
The aims of this CFD Consulting study are to quantify the impact on the environment of sewage discharge from some plant.
Methodology:
A commercial CFD software – MIKE by DHI – is adopted to carry out the numerical CFD Simulation investigation. The hydrodynamic module of MIKE is used to Perform CFD simulation of the tidal flow in the seawaters around Singapore. The water quality module of MIKE is used to investigate the water quality in the seawaters around Singapore.
The water quality parameters considered in the Wastewater Treatment Simulation study are: Enterococci, Faecal Coliform, Ammonia, Nitrite, Nitrate, Phosphate, Dissolved Oxygen, Chlorophyll-a, Total suspended solids.
Outcome & Conclusion
The numerical baseline CFD Simulation results without sewage discharge are validated by the Measurement data from the monitoring station.
Then the numerical results of adding sewage discharge are compared with the baseline to show the environment impact of the discharge.
CFD Fluid Flow Analysis of Hydraulic DTH (Down the hole) Hammer Prototype
The design and numerical simulation of a wear-free fluidic switch based on the Coanda effect for a hydraulic DTH (Down the hole) hammer prototype. The traditional DTH hammer prototypes have around 40-45 parts enclosed within the hammer casing for efficient operation. the major drawback, however, is if one of the components within the hammer fails, the complete hammer assembly has to be opened and the part has to be replaced. The need to reduce the number of moving parts within the assembly is of utmost importance. The fluidic switch assembly was designed in the Siemens Unigraphics NX 10 Cad software and the numerical simulation was carried out in the Ansys CFX simulation software. The major part of the analysis is the extraction of the fluid volume through the hammer assembly. this was accomplished in the Ansys design modeler. A sensitivity analysis was carried out in order to establish the final design of the fluidic switch which can be incorporated into the hammer casing.
Analysis of Flue Gas Flow in The Piping of Circulating Fluidized Bed Boiler
This CFD simulation is about how to depict the flow characteristics of multiphase fluid within the pipe. And then, to design a modification of 3D piping to accommodate the separation of the small solid particles (ashes) from the gas phase along the pipe and also to direct the fluid flow into a more laminar type. The method that was used for the CFD Simulation is Lagrangian for the solid particle and the Eulerian for the gas phase in which they are applied using ANSYS CFX. The separation method has relied upon the gravitational factor and the mass difference between those two phases. After implementing modification of baffles on certain areas, a high portion of ashes can be kept in the ash pit area while the flow can be directed into a more laminar type while it was also able to be distributed in a similar amount of flow rate for all outlets.
Backpressure valve (BPV) and downpipe design
Objective
To suggest design change for downpipe of commercial truck
Methodology
Downpipe is part of exhaust pipings for a truck and it takes exhaust air out from the truck. The Fluid flow after the turbine passes through a back pressure valve and then enters into the downpipe.
CAD data was imported in a neutral CAD format. The surface repair tool was used to check the surface quality (pierced face, free edges, manifold vertices/edges) and then meshed with polyhedral mesh (mesh sensitivity was done to obtain optimum mesh size) along with prism layers. The part based mesh was used to create the final mesh along with custom controls. To perform this CFD simulation, Velocity and temperature profile was used as inlet condition. The profiles were exported as internal tables from an earlier turbine CFD Simulation which was without BPV and downpipe. The table is then imported as a table to apply as an inlet boundary condition. The outlet of the pipe was applied as a pressure boundary. Walls were treated as adiabatic for this analysis. k-epsilon turbulence model was used for closure.
Air was used as Ideal gas. Various monitors & reports are used for post-processing and understanding the convergence of results. Area of design improvements (recirculations and higher velocity related loss etc.) were identified and reported. CFD Simulations were performed for design recommendations and 20% improvement is shown.
Outcome & Conclusion
Pressure drop along with the area of recirculating regions was identified for various BPV opening conditions along with improved results for design suggestions.
CFD Simulation of Gas Flow on the Pipe Ejector
The CFD simulation is about Numerical modeling of the gas flow on the pipeline ejector as to show whether the gas is sucked on by the ejector or not.
The method that was used for the CFD Simulation is the Eulerian as it was only one phase whereas it was performed using ANSYS Fluent.
The Fluid Flow Modeling results from the CFD Simulation showed that the gas was sucked in quite wholly to the ejector due to the far smaller diameter of it compared to the pipeline’s diameter whereas the velocity was constant along the pipeline up to the ejector.
Numerical Simulation of 3D Local Scouring Around Submarine Pipeline
For this CFD Simulation Project, our CFD consultants have already completed 2 dimensional Computational fluid Dynamic simulations and now trying to get my 3D simulations done.
Objective:
The objective of this CFD Consulting study/simulation is to predict the scouring under submarine pipeline as scour under a submarine pipeline can lead to structural failure; hence, a good understanding of the scour mechanism is necessary.
Methodology:
Our aim is to represent a numerical investigation of the scour phenomenon around a submarine pipeline.
The numerical Fluid Flow simulations would be performed using SedFoam, a two-phase flow CFD model for sediment transport implemented in the open source Computational Fluid Dynamics (CFD) toolbox OpenFOAM CFD software. The CFD Analysis study will focus on the turbulence model with respect to the predictive capability of the two-phase flow model. k-ε turbulence models will be checked by completing the numerical CFD simulation.
Outcome & Results
The main outcomes of this CFD Consulting project would be to predict and determine 3D scouring, numerical investigation of scour phenomenon, behavior of two phase flow model and change in scour pattern due to change of particle size of sediment.
Sand Erosion Modelling in the Gas Pipeline Bends
The simulation is about to depict the potential of erosion location on pipeline bends due to the existence of sand within the gas flow. The objective is to apply the best model for the pipeline bend so that the erosion area can be diminished. This was performed using STAR CCM+. Moreover, the method that was used is Lagrangian particle tracking for the sand as this was intended to show the collision area of the solid particle on the pipeline wall. Meanwhile, the Eulerian is used for the gas phase to depict it as one body of flow. The factor that determines the model selection is the curvature of pipe bend, the selection of U bend or S bend, and the pipeline diameter. Consequently, the U pipe model with 2D curvature and diameter of 25 cm was chosen as the erosion has occurred the least on this model.
On-demand Reactivity Enhancement to Enable Advanced Low-Temperature Natural Gas IC Engines
Objective:
To design a reactor to enhance fuel to achieve the combustion of natural gas engines at low temperatures by performing catalytic reactive simulations.
Methodology:
– Exploring design configurations using CAD (SolidWorks Software from SeaCAD Technologies) to get a desirable distribution of air and fuel with non-reacting simulations using ANSYS Fluent Gambit Software and Converge CFD
– Conducting initial reacting flow simulations with Chemkin Pro for simplified geometries.
– Performing reacting Fluid flow simulations for complex geometries with Fluent and Converge and analyzing fuel composition
– Refining design to produce expected output fuel composition. CFD Engine is simulated with this fuel (Converge) to determine performance, ignition temperatures and emissions.
Outcome:
– Experimental results from collaborators are matched with reacting flow CFD Simulation model for a benchtop test reactor with <5% error
Numerical Simulation of a Dynamic/Active Heat Flux sensor on a Flat wall using Ansys (Fluent)
Objective:
In this CFD Turbulent Flow simulation, a Newly developed Dynamic Heat flux sensor was developed and placed on the surface of the Wind tunnel. From the inlet side, 2m/sec to 12m/sec velocity of air was sent through the blower. The difference between Dynamic and passive Heat flux sensor is: Passive/Traditional HTS gives the Local Heat transfer coefficient and surrounding temperature; Dynamic HTS gives the Global Heat transfer coefficient and equivalent surrounding temperature and Experiment Testing results were recorded and it should be validated through Numerical CFD simulation.
Methodology
Ansys ICEM CFD was used for Geometry and Meshing Purpose and Ansys CFD Fluent as a solver. This is a 2-D and 3-D (Real case) Transient Numerical CFD simulation of airflow and Heat Transfer. For Post-processing of the data obtained from the CFD Turbulence modeling, we used Matlab and Fortran 95.
Different geometry was modeled for different cases and created a Hexahedral Mesh with better quality and less skewness.
As fluid flow comes under the Laminar Flow, we also considered a turbulence flow with very little intensity about 1% and wall y+ came around 0.9. Mesh grid independence test was carried for different Nodes and considered the optimum nodes mesh for fast computation. We considered the energy models like K-epsilon, we used Enhanced wall treatment and Menter-Lechner near-wall treatment (Independent of Y+ model) and K-omega SST Model.
We also created a UDF for giving some heat flux at one side up to 4 sec according to the experiment. As a solver, we used Ansys Fluent CFD and the CFD simulations ran successfully for both 2-D and 3-D cases.
Outcome & Conclusion
The conclusion was the average error between the 2-D (Turbulent) and Experimental data was around 9% and between 3-D (Turbulent) and Experimental data was 8%.
Improvement of the lifetime prediction of the silicon fluid in torsional dampers
This CFD Research consultancy project was a collaboration work with Caterpillar. The lifetime of the silicon fluid depends on the temperature of the fluid. At Knorr-Bremse Our CFD Consultant performed the thermal simulation of the damper, while at Caterpillar the thermal model was put into a huge CFD model where the turbulence was modeled with the k-epsilon closure. The transferred information was :
- – The heat flux profiles on the inner walls of the damper from us.
- – The Thermal temperature profile on the skin of the damper from Caterpillar.
The CFD Simulation project was based on an iterative process and after 4 iteration steps we achieved converged results.
Later the results obtained from the CFD simulation were validated by physical measurements.
CFD analysis of turbulent swirling flow instability in the vaneless diffuser
Objective:
To Numerically simulate rotating stall in a vaneless diffuser section of the radial compressor with Simcenter STAR-CCM+ and OpenFOAM and determine critical angle
Methodology:
– Sketched geometry with SolidWorks. Boundary conditions were provided by the Elliott company
– Analyzed Skewness and Orthogonality to refine the mesh. Conducted CFD simulations with High-Performance Computing
– Compared RANS, URANS, and LES models. Only LES predicted rotating stall (α≤ Critical Angle).
– Compared pressure coefficients & critical angle to experimental data provided by the company
Outcome:
– Successfully modeled rotating stall using STAR-CCM+ CFD Software and OpenFOAM
– Performed dynamic pressure analysis to prove rotating stall in the diffuser
– Accurately predicted the critical angle with error < 2%
Most of our CFD consulting research and CFD Client work has revolved around evaluating different numerical methods/approaches in regards to their accuracy, effectiveness, and ease of use, always with complex engineering flows in mind.
Extend the gas turbine engine performance for client in Gas turbine industries
By using the well-known Bryton cycle for the CFD simulation, the combustor outlet temperature must increase to have higher efficiencies. However the turbine inlet temperature increment creates harsh environment for the downstream components of the combustor. This requires designing an efficient cooling technique in this area.
In the traditional Thermal cooling system, the increase in blowing ratio enhances cooling effectiveness. But, the coolant does not well attach on the surface at higher blowing ratios. This necessitates restructuring the cooling holes. A useful way can be trenching cooling holes at the combustor end wall surface and the alignment of row trenched holes; however, this has not been seriously considered as a Engineering solution up to the present time.
Therefore, the present CFD consulting study has been conducted in order to investigate the effects of trenched cooling holes with different depths and widths at blowing ratio of BR=3.18 on film cooling effectiveness. The two-dimensional representation of a part of combustor end wall was Computationally simulated and a program was written in the finite difference method by MATLAB software in order to find the optimum depth and width.
Furthermore, the three-dimensional representation of Pratt and Whitney’s gas turbine engine was selected to investigate the effects of cylindrical and row trenched cooling holes with an alignment angle of 0, 90 and +-60degrees at different blowing ratios of 1.25 and 3.18 on film cooling effectiveness and mixing processes adjacent the end wall surface.
To achieve the objective, the CFD model was simulated and analyzed with the commercial finite volume package, Ansys CFD FLUENT 6.2.26. This study overall findings show that the application of the row trenched cooling holes near the combustor enwall surface increases the effectiveness of film cooling up to twice its value compared to the cooling performance of baseline case.
Microchannel Solar Receiver Project
- Thermal Simulation modeling and design of microchannels with circular pin fins using STAR-CCM+ CFD Thermodynamics Simulation.
- Work involved computational modeling of coupled fluidic and heat transfer processes occurring in a unit cell of the Microchannel Solar Receiver (MSR). Conducted detailed parametric CFD Analysis study varying the geometric parameters for microchannel pin fin design to achieve maximum thermal efficiency with minimum pressure drop.
- Developed an optimized fluidic design of unit cell design of microchannel solar receiver with circular pin fins that meets efficiency goal and pressure drop and temperature goals.
Porous media CFD simulations
- CFD simulations using Lattice Boltzmann based solver – PowerFLOW to analyse essential rock properties.
- The main objective for this CFD Simulation is developing scripts in Python, estimate resistance values for porous media and run simulations using porous media model in PowerFLOW and find out permeability.
- Porous media CFD simulations on micro CT scan images to account for unresolved porosity.
CFD Simulation involving High Knudsen number flow
- CFD simulations to study flow in microchannel and microtubes for high Knudsen number flow.
- Because for unconventional rocks like Shale, Knudsen number is high due to high pressure and smaller length scales.
- Therefore, to study behaviour of flow in high Knudsen number is very important. Developed code/scripts to automate simulation and analyze functionality using object oriented programing in Python for high Knudsen number flow.
CFD Simulation for Heat Transfer Applications
The convection heat transfer has applications in a wide variety of engineering and technology applications.
To mention some of them, the cooling system should be mentioned which is the main concern of the factories and industries such as microelectronics. Thus, using some cooling systems with strong and improved cooling methods, is something necessary.
In this Thermodynamics Simulation CFD study, a hot obstacle which is located in the middle of a rectangular enclosure is cooled, and the flow is considered two dimensional, steady, laminar, and incompressible. This enclosure has an inlet and outlet, and the fluid is entered from one side and gone out from the other side (forced convection heat transfer). All the walls are insulated and the obstacle is hot. The effects of different parameters used in this Heat Exchanger Simulation such as volume fraction of nanoparticles, Reynolds number, Hartmann number, and the outlet place on the heat transfer rate has been investigated.
Outcome and Conclusion
The Thermal Analysis results show that the average Nusselt number and heat transfer rate increases as the outlet place goes down. Besides, by increasing the Reynolds number, the isothermal lines are compressed and the dimension of the cold spots near the entrance augments. This phenomenon causes the isotherms to come near the hot obstacle and the heat transfer increases. Moreover, by changing the volume fraction of nanoparticles, no changes are observed in the vertical velocities and the general pattern of the flow as far as the nanoparticles have little effects on the viscosity of nanofluids.
Finally, by increasing the Reynolds number and volume fraction of nanoparticles, the average Nusselt number and heat transfer augment.
Thermal Heat transfer: Radiator core selection
The main purpose of this CFD Simulation study is to determine the optimal radiator core selection for the FSAE race car. During that particular season, there were two potential radiator suppliers for our team, namely Pace Products and PWR. As both companies provide a wide range of core selections, a simple CFD heat transfer model was used in order to determine which core would provide the highest cooling capacity.
The heat exchanger model in ANSYS Fluent Flow Simulation Software was used in this Heat Exchanger Simulation study. The thermodynamics values used were those of water, as water was the coolant. The inlet temperature values were entered using the water and air temperature sensors installed on the car. The number of rows, column, and passes were based on the cores’ values specified by Pace Products and PWR.
After a number of core Steady State Thermal Analysis simulations were done, the heat rejection values were compared. In the end, it was decided that one of the cores provided by Pace Products would be used in the car.
Development of next-generation industrial gas-liquid mixing device for hydro-processing reactors used in refineries
Eulerian-Eulerian multiphase simulation with mixture drag model to account for the interaction between the gas and liquid phase was employed to test the different conceptual design of gas-liquid mixing device.
Based on the CFD analysis of the Centrifugal Pump Simulation, a new gas-liquid mixing device was developed which provides excellent mixing performance, occupies less space and easier for maintenance compared to the previous generation gas-liquid mixing device (Applied for world patent).
Development of methodology to understand and quantify the relationship between the catalyst particle shapes and catalyst deactivation.
Multi-domain single-phase CFD simulation with user-defined function to model the reaction and diffusion inside was developed to simulate the transient carbon formation process for different particle shapes. Based on the CFD FSI analysis, particle features that are less favorable for catalyst deactivation was reported (Published in peer-reviewed international journal).
Conditioning Tower for a Cement Manufacturing Plant
Water was sprayed into the tower to cool and aggregate particles in the air. The problem was uneven wetting of the product at the bottom of the tower. The flow in the tower was analyzed. A simple model with particle tracking was used to determine the flow of air and water to determine how and why the water was accumulating more in one area of the tower. A range of flow correction devices was compared to determine the improvement in the air flow and water distribution. The best (and simplest) solution was presented to the client. The device was only being installed by the time I finished my term at the consultancy (part-time work), but the feedback I received indicated the device was working.
Development of next-generation industrial gas phase hydrocarbon fuel burner device for chemical reactors used in oil & gas industries.
Single-phase CFD simulation with eddy dissipation/finite rate chemistry combustion model to account for the combustion and reforming reactions were employed to test the different conceptual design of air-blown burner device.
Based on the CFD analysis, a new burner device was developed which provides 80% lower pressure drop and better temperature mixing compared to the previous generation burner device (Applied for world patent).
Milk frother CFD simulation
Apart from being highly proficient in the use of Simcenter Star CCM+, Our CFD Simulation Consultants have experience in other projects which Our Consultants have done in CRADLE scTetra. a MSC software company.
Objective:
Objective of the CFD Simulation is to find the vertex formation to predict the uniform mixing, rise in temperature of the milk and to predict the possibility of milk scorching under high speed rotation of the impeller.
Approach:
- Assumption: working fluid water, in-compressible, No Cavitation
- set the initial condition like water height. temperature..
- CFD Analysis settings: Transient state,Turbulence: RNG K-e, free surface VOF (interface capturing method), Bottom of the jar boundary fixed heat flux q, for the rotating impeller moving element with dis-continues mesh, all walls: No-slip , Top face of the jar: open (fixed static pressure), time step: 0.0001 s (fixed)
- Test run, Final run
Outcome and conclusion:
extraction of temperature profiles, iso-contours of VOF and velocity vectors and contours.
from the CFD Simulation results it has observed that void are formed at the bottom surface forms big bubbles which may be over predicted as the present CFD Simulation has not incorporated cavitation.
from the results it has concluded that uniform mixing of the fluid maintains the uniform temperature through out the liquid volume, temperature has rise as expected by the client. bottom surface temperature of the jar indicate the no scorching possibility.
Also for the given height, liquid will not spill out of the jar.
Prediction of Dew condensation on the display Case for cold storage
Objective:
To use CFD Simulation to predict the dew condensation on the front glass of the display case, this results in poor visibility of the product inside.
Approach:
- Assumption: in-compressible, products are kept at constant Thermal temperature.
- Initial condition: set the domain temperature and humidity, display case internal temperature
- Settings used for the Jet Fan CFD Analysis: Transient state, buoyancy is considered, Turbulence: Linear low Re model, Humidity and dew condensation considered. Wall: No-slip walls, heat transfer considered. fan model: blower type. time step 0.001 s (fixed)
- Test and Final run
Outcome and Conclusion:
extraction of temperature profiles, humidity and velocity vectors and contours. dew condensation profile on the front glass.
From the CFD Simulation results it has been concluded that the possibility of dew condensation on the glass surface
Apart from general CFD Simulation, Our CFD Consultants have deep exposure to electronics thermal management, Architectural CFD. Our CAE Consultants worked extensively on these above area.
At present Our CFD Consultants am working on FDS Fire Dynamics Safety for Numerically modeling fire Outbreak scenarios in basements, office space, warehouse ..
CFD code development for blood flow along a bifurcating artery
Objective:
The purpose of this blood flow CFD consultancy project is to develop a Navier-Stokes finite difference solver to simulate the coronary artery disease
Methodology:
– A bifurcating clogged artery domain was setup and dimensions and boundary conditions for the Blood Flow CFD Simulation were taken from medical articles
– Developed Finite difference Navier-Stokes’ solver with & performed grid dependence study to maximize accuracy
– Compared simulated CFD Simulation results from the solver to a commercial CFD Software code (ANSYS Mechanical CFD Software)
– Analyzed gauge pressure to find clot thickness at the point of hypertension
Outcome:
– Developed fully functional transient solver using Fractional Step Method
– Accurately predicted the clot thickness for which a patient experiences hypertension
– <2% error in comparison with ANSYS CFD Post processing
Cardiovascular Flow Dynamics Simulation Modeling
Objective:
The objective of of this CFD consulting project is to predict cardiac arrest in real time as an supplement to specialist diagnosis
Methodology & Approach:
To conduct Blood Flow CFD Simulation superimposed on MRI scan of aorta to obtain flow results with respect to the critical backpressure.
The main agenda was to accelerate the computational process of the CFD Simulation by 20X times with a hybrid CPU-GPU based strategy
Outcome & Results:
Being implemented by Samsung Korea in one of their core medical diagnostic software system
Aerodynamics: Sidepod/front wing/radiator optimization
In this CFD Simulation study, the main purpose was to determine the optimal sidepod/front wing configuration, so as to maximize air flow into the radiator, as well as the positioning of the radiator inside the sidepod. As previous iterations of the FSAE race car were plagued with cooling issues, it was decided that solving cooling problem would be the main priority, with small compromise on the aerodynamics of the car.
A half car CAD geometry was simplified and modified using SOLIDWORKS CAD and Solid Edge, and the mesh was created using ANSYS CFD Premium. Front wing open and closed configurations, and sidepod with and without slots were considered. As for the positioning of the radiator, the configurations studied include vertically mounted, leaning backwards, and leaning forwards.
ANSYS Fluent 3D Fluid Simulation Software was used in this Air flow Analysis study. A pressure drop zone was created in the space of the radiator inside the sidepod. The pressure drop parameters were obtained from the radiators’ sponsors as mentioned above. All models involved in the Airflow Modeling Simulation use k-epsilon turbulence model as basis of comparison. The inlet velocity inlet was chosen to be the average speed of the car during the previous race. Since the main priority is to resolve cooling issue, air flow across the pressure drop region would be compared among different configurations studied. The drag, downforce and center of pressure values were collected as well.
Based on the CFD Analysis data, it was decided that the car would be run with open front wing configurations, as well as open slots on the sidepod in order to maximize air flow into the sidepod. The radiator is to be mounted leaning forward with respect to the car. The improvement in cooling when this configuration was used was also confirmed with real track testing, with water and oil temperatures considerably lower than those during the race.
Numerical Aerodynamics investigation of Flapping Wing Design
This CFD Aerodynamics Simulation project is part of a preliminary defense research program of DSTA.
Objective:
The Primary objective of the CFD Consulting is to investigate the lift and drag force of the flapping wing profile. A 3D moving grid based on the transfinite interpolation is generated which has better adaptation than the deforming grid for flapping wing. A 3D finite volume method solver is developed as part of our FSI Analysis Services to adapt for the calculations of flapping wing.
All the code including mesh generation and flow field solver are self-developed by FORTRAN. The effects of every flapping control parameters on the aerodynamic characteristics of flapping wing are investigated by the FSI Consulting Engineers.
Outcome & Results
The numerical results from the CFD Analysis show that the pitching angle contributes to the average lift and will slightly decrease the thrust force as well.
Numerical Simulations of Transonic Buffet on a Half Wing-Body Configuration.
Our Team of CFD Consultants are experts with extensive experience with Simcenter STAR-CCM+ and Ansys Fluent. Both solver are similar finite volume based and has similar physics models.
Some of the recent projects we did using CFD Simulation includes work focused on the characterisation of buffet unsteadiness and its onset. The CFD simulations were performed using a structured mesh, after a grid sensitivity study has been assessed.
RANS and DES Computational calculations were conducted at a fixed transonic Mach number for a low and a high incidence case, using a finite volume solver. Several turbulence models and numerical schemes were tested when Solving the . It was concluded that the biggest sensitivity among the numerical parameters is the choice of the turbulence models.
For the unsteady CFD simulation, a time-step size has to be chosen depending on the time scale of the flow unsteadiness. The time-step size chosen for all DES simulations is 2 x 10-6s.
This precaution has been taken to prevent Soving inaccuracy in case the buffet frequency is significantly higher for some combination of angle of attack and Mach number. Steady-state solutions converge
only when the flow does not present a large separated zone on the upper surface of the wing.
Then, time-accurate CFD simulations have to be considered.
It has been shown that for all Mach numbers, when considering small angles of attack, the shock induced separation has a limited size and the flow is steady. Increasing the angle of attack, the separated zone close to the wing tip begins to oscillate and the unsteadiness moves towards the fuselage.
CFD Analysis on Vertical Axis Wind Turbine (VAWT) Platform
Simulation Objective:
The objective of this CFD Simulation report is to develop best practice to simulate straight-type Vertical Axis Wind Turbine (VAWT). The design of VAWTs has been developed such as Blade Element Momentum theory (BEM) and Double Multiple-Stream Tube model (DMT). However, the design tools may not accurately predict turbine performance. So CFD analysis performs essential role in the design stage to accurately optimize output power. A validation study of a wind tunnel test is performed as benchmark for CFD modelling, and further a 2 MW VAWT with various RPMs is studied for design purpose.
Methodology/Approach:
Three-dimensional (3D) unsteady RANS model is used to simulate turbine performance and fluid flow, and the employed turbulence model is k-ω SST. The SIMPLE scheme is used to solve the coupling of pressure and velocity. The inner iteration is fixed to be 10 for each time step. Temporal discretization is second order. Unstructured Polyhedral mesh is used in the CFD Simulation to discrete the computational domain. Fine meshes in the critical regions near interface and blade are created to accurately capture the fierce flow characteristics. The prism layers attached to the blade surfaces are generated to fully resolve the turbulence viscous boundary layer. The sliding mesh technique is used to allow the mesh adjacent to the blades to rotate. The interface separated the stationary region and the rotating region. To develop the best practice in CFD Simulation, the sensitivity tests are performed for the convergence on grids and time steps.
Outcome and Conclusion:
The best practice is developed on the VAWT numerical modelling using Simcenter Star CCM+. The wind tunnel testing data on a two-bladed turbine is used to benchmark the three-dimensional CFD Simulation results. The 2 MW wind turbines with various blade chord lengths are modelled. The numerical results have shown that the turbine with certain dimensions performs best in the power output. The dimensions and performance characteristics obtained from the CFD analysis on the 2 MW turbines will be employed in the VAWT platform design.
CFD Modeling of Air flow around Vortex generators
Our CFD Consultant also studied the flow around vortex generators, small devices typically used on wind turbine and aircraft wings in order to delay separation. This achieved by mixing high momentum fluid into the boundary layer through the wing-tip vortex created around the vortex generator.
Objective:
The goal of this study was to evaluate whether the increase in accuracy of a wall-resolved RANS simulation was significant enough to justify the additional computational cost, compared to using case specific models (namely the so-called BAY model), that substitute the vortex generator with a force term, significantly reducing the resolution requirements. It was shown from the CFD Simulation that wall-resolved RANS (here a finite volume code coupled with either the Spalart-Allmaras or the SST k-ω models was used) provides a rather significant increase in accuracy and, therefore, should be considered instead of the simplified models.
For more details, Our CFD Consultant could provide a structured document presenting the cases in full and some key results, if you would prefer that.
Steady and Unsteady Analysis of Turbine Stage of Small Turbofan & TurboFan Engine
Objective: To carry out the unsteady simulations of turbine stage and its comparison with CFD steady analysis
Methodology: Grid generation in NUMECA’s AutoGrid5 | 3D analysis in ANSYS-CFX
Outcome: Results obtained from the unsteady analysis is within limits as compared to steady analysis results and a lot of time can be saved with steady analysis.
CFD analysis of airflow through a C-D nozzle
Objective:
CFD analysis of airflow through a C-D nozzle to capture normal and oblique shock and expansion fan.
Approach:
Using a density-based solver in ANSYS Gambit Fluent with quadrangle mesh the flow was modeled as a steady-state with laminar and kwSST turbulence models for different conditions of back pressure at the nozzle exit. A code was developed in MATLAB to verify with the analytical results.
Outcome:
Subsonic flow is observed up to exit pressure ratio of 0.93 while Internal Normal shock at 0.68. As this ratio keeps decreasing normal shock at exit, oblique shock outside nozzle and expansion fan can be observed.
Paint spray simulation through Coating Hood
Objective:
Paint spray simulation through Coating Hood to study the effect of suction pressure on particles and their behavior with the wall.
Approach:
Using OpenFOAM CFD Software and sprayFoam solver to perform the simulation of air and paint spray atomization was simulated with Ritz-Diwakar breakup model and Rosin Rammler size distribution with no chemical reaction involved.
Outcome:
Suggested the internal dome design to achieve minimum sticking of particles inside and maximum suction of unused spray.
Cascade Analysis of Turbine Blade Sections of Small Gas Turbine, Small Turbofan, and Turbofan Turbine
Objective: To carry out the CFD analysis of turbine blade sections and its comparison with the experimental data
Methodology: Grid generation in NUMECA’s AutoGrid5 | 3D analysis in ANSYS-CFX
Outcome: The CFD results were within acceptable limits compared to the experimental data
CFD simulation study on Aeroacoustics in Unsteady Exhaust flows.
This current CFD study’s objective is to validate the capability and robustness of ANSYS Fluent CFD software acoustic models in predicting aeroacoustics noise sources with existing anechoic chamber acoustic data.
The methodology planned is to model the experimental setup in ANSYS Fluent Flow environment with FW-H acoustic model, as well as direct method from unsteady LES simulations.
Outcome & Conclusions
The expected outcome of the study is to understand the capability and limitations of ANSYS Fluent Software in Computational aeroacoustics noise predictions and utilise the learning outcome in future aeroacoustics CFD simulation project.
CFD simulation case study on Exhaust flow.
The objective of the study was to investigate the impact of different exhaust design parameters such as exit angle, opening area, etc. The case studies were started with CAD geometry preparation in Siemens NX and then exported to ANSYS workbench and Fluent for CFD simulation and post-processing.
At the operating flow rate / point, simulation results were validated with recorded experimental test data. A grid convergence study was carried out as well to gain confidence in CFD simulations. Pressure and velocity contours were plotted and communicated with the project team for improvement and discussion. The outcome of this CFD study on exhaust flow helped in guiding the project team on the difference between design points and reduced prototyping resources needed as decisions can be made to narrow down the design direction based on CFD simulations.
Preliminary CFD analysis for the comparison of two exhaust brake valve designs.
A new flap valve design had been developed in which there was almost no leakage at the closed flap position. This new design required modifications not only in the valve but also in the tube’s geometry. Due to the sudden cross section changes in the tube (in the original design the tube’s diameter was constant) a larger energy loss was expected for the new design. Our client asked for a comparison of total pressure drops through the valves at 10° from the closed position. In the fluid domain there were small gaps between the flap valve and the wall of the tube. These little gaps made the mesh generation to be extremely challenging. Our CFD Consultant ran steady case CFD simulation with taking into account the turbulence by the k-omega SST model. The results revealed that the sudden cross section changes did not significantly increased the pressure drop along the valve.
CFD Modeling of Soot Particle Formation
- A new phenomenon soot CFD modelling approach have been proposed towards the formation of soot particles, particular in different hydrocarbon classes on soot characteristics, which guides in the selection of commercial surrogate fuels in clean engine combustion.
A full-cycle engine CFD model including valves movement and intake/exhaust ports have been employed in this FSI Simulation under KIVA-CHEMKIN platform, coupled with new soot model and fuel chemistry mechanism to test engine performance. - Sensitivity analysis of main combustion reaction path of diesel surrogate fuel under varies combustion boundaries was done under STAR-CD platform.
The information of chemistry reaction paths, flow velocity, combustion and emission charateristics were anaylized in post-processing of the Computational Fluid Dynamics analysis.
3D CFD analysis of Components in IC Engine Exhaust Layout using OpenFOAM
Field of Work: Transient Thermal Analysis
Simulation Objective: This project was done for BOSCH Ltd., Bangalore (India), where the prime objective was to analyze the flow of exhaust gases and atmospheric air in the EGR valve specifically been developed for single cylinder engines.
The methodology used: The concept was discussed among the team of four peoples and finally Orifice-type of EGR valve concept was approved for the analysis. I was assigned to design and do CFD analysis of the concept. I have used Pro-E for CAD, ICEMCFD for meshing (tetra mesh) and OpenFOAM for CFD analysis.
Later, for post-processing, ParaView, Gnuplot and Libre office (open-source, default office program in Ubuntu OS) is used
Outcome and Conclusion: It was found that, during the exhaust stroke of the engine, when both inlet and exhaust valves are open, the pressure in the exhaust valve is very low compared to the inlet. Hence, the air was moving out of the EGR valves and was not able to mix with exhaust gases. That is why, instead of the air-exhaust mixture, only the fresh air was supplied to the engine.
Finally, it is established that spring-loaded elbow type EGR valve can perform better than the newly-designed Orifice-Type EGR valve.
Aerodynamics Simulation of Airflow around the DrivAer car model
Our CFD consultants have worked on simulating the flow around the DrivAer car model. DrivAer is a fairly complex car model designed by merging the BMW 3 series and Audi A4. The main goal of the CFD Simulation was to evaluate whether wall-modeled Large Eddy Simulation (WMLES) is accurate enough in the prediction of the aerodynamic coefficients as well as the vortical structures created by the geometry of the car, e.g. the wheels and pillars.
The CFD Simulation results shown that WMLES provides satisfactory results at a greatly reduced cost (compared to wall-resolved LES), even with very simple wall models. A finite element code, using a formulation based on fractional step method, coupled with an energy-preserving Runge-Kutta temporal scheme and a simple wall law were used in these CFD simulations.
Aerodynamics CFD Simulation of Formula SAE car
Objective:
CFD Simulation of side wind Loading Effect on Formula SAE car.
Approach:
Using SimScale CFD software a model a FSAE car was meshed using snappy hex mesh with SIMPLE solver and Komega SST turbulence model including the effects of radiator porous media and rotating wheels (MRF)
Outcome:
Front wing-Negligible difference in drag in the moving direction. Almost thrice the effect of drag in the side wind direction.
Rear wing-Negligible difference in drag in the moving direction. Almost 6 times the drag force as compared to no side wind. The wake of the car is greatly disturbed.
Research project at NUS collaborative with Bureau Vertias, supported by MPA
Objective:
The objective of the CFD Consultancy project is to accurately quantify the viscous damping effect and flow structure of resonant fluid between side-by-side FLNG-LNG Carrier under a particular wave environment.
Methodology
Our CFD Consultants used the open-source CFD package OpenFOAM and its extension library packages for marine/offshore CFD simulations. The results were cross-validated by Simcenter StarCCM+ The CFD simulations have good agreements with the experimental measurements.
Outcome & Results
Our Consultants confirmed the vortex shedding flow structure in the gap between two long ships and proposed simple method to estimate the viscous damping effect.
Hydrodynamics of a Boat Hull
I was approached by a boat builder to analyze their new design of a 52 ft catamaran motorboat. This was to determine the top speed, power requirement and other characteristics of their hull shape. Their initial hull design was not suited for the high-speed conditions they desired. So a more appropriate hull shape was proposed which met their requirements. The first boat is still under construction.
Flotation Tank and Flow Control Valves
A bank of settling tanks was analyzed to determine the correct sizing of flow valves and the height of the outlet back-pressure pipe for required flow characteristics between tanks. The design was approved by the time I finished my term with the company (short-term contract). No construction had started.
Let us quickly touch on the fundamental Methodology of Engineering Simulation and Computational Fluid Dynamics (CFD) mean and how they fit into your engineering development workflow processes.
What is Engineering Simulation
Engineering Simulation is an integral and core part of the digital prototyping process. Fundamentally the 3d CAD model of your product concept design is your digital prototype.
It is from this prototype model that critical engineering design information is verified, Tested and Validated along each of the engineering development function in the company, from Manufacturing to Production and finally to Sales and Marketing
Engineering simulation takes place predominantly in the early Test and Validation phase of the digital prototyping process, during which critical questions need to be answered. This includes questions such as:
– Can the design withstand the loading forces? Will the design break?
– How light can the design be made while optimizing it for maximum strength
– What is the physical performance like when the temperature changes
Why Engineering Simulation
Engineering Simulation allows companies to develop better products quicker and at a cheaper rate
1. Save Time & Money
Traditionally, questions concerning a design performance have been answered through the Building and Testing a large number of physical prototype iterations which is an extremely Costly and Time-consuming process.
By leveraging on engineering simulation, you can test digital prototypes in a virtual environment, thus helping to save time and money as fewer physical prototypes are needed for testing.
2. Early Engineering Insights
Engineering simulation provides Accurate and Reliable results early in the design development process to help companies make better-informed engineering decisions to optimize their products.
It also allows Failure modes to be identified and Defects to discovered early in the engineering design life-cycle where there is flexibility for corrective modifications allows changes to be implemented relatively inexpensively.
This helps tremendously in the creation of higher quality products and prevents costly product recalls when the product is sold.
3. Accelerated Testing Cycle & Rate of Innovation
In a virtual simulation environment, designers and engineers have the freedom to test and Explore more what-if scenarios because engineering simulation is not constrained by physical size, cost, or external environmental conditions.
As the performance of specific Engineering designs when subjected to specific external conditions can be accurately predicted, it helps to accelerate the design testing cycles involved in optimizing the Materials and Design features.
4. Complete Picture
Through the use of CFD simulation analysis, it is able to give a complete view of the fluid flow behavior.
This accurate engineering insight helps to facilitate questions and critical thinking which is important for driving innovation.
This is in contrast to the individual testing of each iteration of physical prototypes, which only provides discrete pieces of test data