Determining Thermal Test Requirements for Automotive Components

Abstract

Component thermal response is dependent upon numerous factors including the atmospheric temperature, heat sinks and sources, vehicle use time, etc. The number of significant thermal cycles and time at temperature for many components will be related to the number of times the engine is started. This paper provides a methodology to determine the number of significant thermal cycles and time at temperature a product will experience in 10 years which will depend upon engine starts. These calculations provide the basis for an accelerated test requirement to qualify the product based upon customer usage measurements. Because of the trace ability and linkage, the methodology is more marketable to internal and external customers, and less likely to be questioned or arbitrarily overruled. It also enables relative severity assessments for historical customer requirements compared with field needs. © 2004 John Wiley & Sons, Ltd.