Correlating HVAC Vehicle Interior Noise to Sub-system Measurements

This paper discusses the relationship between the Heating, Ventilation and Air-Conditioning (HVAC) subsystem (module) and vehicle noise levels from test results. Vehicle measurements were performed in semi-anechoic room with a binaural head at driver location. The reverberation room measurements on the subsystem level were performed on modules without ducts and at pre-selected inlet restriction. For a given vehicle segment as defined by the J.D. Power & Associates, the interior vehicle noise levels show a good correlation to the module noise over the entire flow rate range of the HVAC operation. The module and vehicle noise strongly depend on the vehicle segment. The results presented here can provide insight to the vehicle noise trends from module noise measurements and in writing vehicle and module noise level specifications.