Comparison of Experimental NVH Analysis Techniques on Automotive HVAC Systems

Automotive HVAC systems contribute to acoustic discomfort caused by high interior noise level especially at extreme climate conditions. Progress in vehicle acoustics has lead to more NVH optimization efforts concerning air handling devices. Various testing and analysis techniques are used at Visteon Product Development Climate to investigate noise and vibration problems. Four of them are chosen as examples. Sound Power can be determined with the sound intensity method or the reverberation chamber method. A comparison of these methods is performed. The vibrational behavior of air handling systems is investigated with experimental modal analysis and running mode analysis. Both techniques are applicable for air handling units.