Aerodynamic Design of Heavy Vehicles Reporting Period April 15, 2002 Through July 15, 2002

[摘要] Activities for this quarter include an effort to simulate the flow structure in the wake region of the trailer and in the gap region between the tractor and the trailer for the GTS geometry. Two-dimensional simulations have been conducted on both flow structures using LLNL's ALE3D code. With the information obtained from these calculations, three-dimensional (3D) grids are constructed for the wake and the gap regions. Due to complexity of the required grid generation, two different grid generation tools have been utilized. The ALE3D code and NASA's Overflow code are both being used for the 3D simulations; ALE3D for large-eddy simulation and Overflow for Reynolds-averaged Navier-Stokes simulations. The wake results will be compared to the NASA 7 x 10 wind tunnel experiment and the gap results to the USC gap flow experiment. The NASA 7 x 10 wind tunnel simulation has been finalized with two different grid topologies. These results will provide the proper boundary conditions needed for the GTS in the tunnel flow simulations. Significant progress has been made in understanding and applying the NASA's Overflow code and the overset grid technology. In addition, we continue to implement advanced algorithms in LLNL's models to improve simulation speed and accuracy and to verify and validate these advanced simulation tools.

[发布日期] 2002-08-08 [发布机构] Lawrence Livermore National Laboratory

[关键词] Boundary Conditions;Aerodynamics;Geometry;Wind Tunnels;Simulation