This content is not included in your SAE MOBILUS subscription, or you are not logged in.
The Effect of Boundary and Geometry Simplification on the Numerical Simulation of Front-End Cooling
ISSN: 0148-7191, e-ISSN: 2688-3627
Published February 23, 1998 by SAE International in United States
Annotation ability available
The maturity of Computational Fluid Dynamics methods and the increasing computational power of today's computers has allowed the automotive industry to integrate CFD into the mainstream design process in many areas. As the application of CFD technology is moving from the component level analysis to the system level, the complexity and the size of the models increases continuously. A successful simulation requires synergy between CAD, grid generation, solvers and post-processing so that a timely solution can be obtained that influences the design directions.
The complexity of the simulations introduces several issues that affect the acceptance of these methods including but not limited to the accuracy, grid independence, influence of boundary conditions, level of geometry detail. The investigation of these issues is the purpose of the current work. The flow around a family sedan has been investigated using a commercial code, and solutions have been obtained for different test conditions. The grid generation was based on a tetrahedral unstructured technology. This approach provides the means for fast and efficient generation of volume meshes for complex geometries. The influence of the geometry detail on the results was investigated by comparing two models, one with all the major underhood components included and a second with a simplified engine and most of the underhood components removed. The flow rate through the cooling package was used as the influence gauge. Two tunnel configurations were used to investigate the effect of the tunnel inlet conditions on the cooling flow rate. Again the flow rate through the cooling package is used to judge the influence of the boundary conditions on the solution. The influence of the grid on the solution was also investigated by applying local refinement in the regions of high gradients. Numerical results for the flow rate through the cooling package are presented and compared with the available experimental data. The usefulness of the approach and implications of the different factors in the successful implementation of the method is also discussed.
|Technical Paper||The Optimum Design of Engine Cooling System by Computer Simulation|
CitationAndra, R., Hytopoulos, E., Kumar, K., and Sun, R., "The Effect of Boundary and Geometry Simplification on the Numerical Simulation of Front-End Cooling," SAE Technical Paper 980395, 1998, https://doi.org/10.4271/980395.
- Ecer, A. Toksoy, C. Rubek, V. Hall, R. Gezmisoglu, G. Pagliarulo, V. Caruso, S. Azzali, J. “Air flow and heat transfer analysis of an automotive engine radiator to calculate air-to-boil temperature” SAE Intl. Congress and Exposition Detroit, MI 1995
- Blumcke, E. Nefischer, P. “Improved engine cooling systems using calculation methods,” Proc. Vehicle Thermal Management Systems London, England 1995
- Bauer, W. Ehrenreich, H. Reister, H. “Design of cooling systems with computer simulation and underhood flow analysis using CFD,” Proc. Vehicle Thermal Management Systems London, England 1995
- Fellague, Kader A. Hu, S. Willoughby, Donald A. “Determination of the effects of inlet air velocity and temperature distributions on the performance of an automotive radiator,” SAE paper 940771 , SAE Intl. Congress and Exposition 1994
- Ashmawey, M. Berneburg, H. Hartung, W. Werner, F. “A numerical evaluation of the thermal effect of the new V6 engine on the underhood environment of the 1993 Opel Vectra,” SAE paper 930295 1993
- Chua, K. Bilanin, A. J. Olson, M. E. “Engine compartment heat rejection analysis via Navier-Stokes simulations,” SAE paper 932971 1993
- Balachander, R. Hytopoulos, E. Kumar, K. Shih, T. Malan, P. Sam, R. “Underhood/Underbody flow simulation using unstructured grid technology,” Procs. 3rd International Conference on High Performance Computing in the Automotive Industry,” Sheh M. 1996
- Blake, K. R. Spragle, G.S. “Unstructured 3D Delaunay Mesh Generation Applied to Planes, Trains and Automobiles,” AIAA Paper 93-0673 1993
- Mathur, S.R. Murthy, J.Y. “A Pressure-Based Method for Unstructured Meshes,” Fluent Inc. Technical Memorandum TM-234