2009-26-0058 HVAC Module CFD.pdf

Symposium on International Automotive Technology 2009 1 Sumit Tiwari, Roopak Agarwal, Puneet Saxena and James Acre Delphi Thermal Systems, India CFD-Based Design Enhancements in Passenger Vehicle HVAC Module SAE Paper No. 2009-26-058 Copyright ? 2009 The Automotive Research Association of India, Pune, India ABSTRACT The Heating Ventilating and Air Conditioning (HVAC) module is a single unit designed to provide passenger comfort and safety in any automotive application. In the present competitive environment cost saving and short turn-around time are two major challenges for the development of automotive HVAC modules and systems. However, to make progress in this area, a good understanding of the flow behavior within the module is essential. Computational Fluid Dynamics (CFD) tool reduces the overall development time and ensure an optimum comfort level to passengers in the vehicle. In this paper, attempt has been made to simulate a passenger SUV HVAC module at different modes to examine flow field development and temperature distribution inside the module. All the CFD results have been compared and validated with wind tunnel obtained test results. A three dimensional model with FLUENT solver and GAMBIT, TGrid meshing software has been used throughout the study. INTRODUCTION Nowadays human comfort and safety are the most important criterion to develop any passenger vehicle. HVAC system has almost become near-standard on all new vehicles sold today because it provides driving comforts, reduces road noise, improves safety and enhances driver vigilance. To Improve air conditioning performance and occupant thermal comfort requires an thorough understanding of the fluid motion prevailing in the HVAC system. HVAC system dynamic airflow should be based on achieving uniform passenger comfort inside the passenger compartment at the specified maximum cooling and heating conditions. However care needs to be exercised in air flow selection because increasing airflow leads to grea