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During thermal performance testing, achieving thermal balance between two fluid mediums of any heat exchanger is critical. Heat balance ratio (HBR) measures the heat transfer imbalance between two sides (source and sink) in a heat exchanger and also helps in ensuring accuracy of test data. There could be many factors which may lead to the imbalance in thermal performance of the sample under testing e.g. sensors accuracy, test operating range, sample orientation, hysteresis in the data acquisition systems etc. Therefore, a testing procedure needs to be established to achieve a better heat balance ratio as low as less than ±5%, which accounts for errors during instrumentation processes, flow losses & manual errors during testing. The current experimental study focuses on a typical coolant aluminium brazed heater core product which is used in automotive applications for passenger cabin heating during the cold climate conditions, windshield demisting and defrosting.

The durability evaluation of overhanging components of a vehicle (Ex: horn, radiator) is a challenge to durability engineers as resonance plays an important role in determining their fatigue life. As resonance cannot be avoided always, it is desirable to develop methods to evaluate life of the component in the presence of resonance. Though the existing vibration test standards suggest test profiles to evaluate resonance failures, there are cases in which, these methods do not yield the proving ground results. This may lead to unnecessary overdesign or unrealistic failures. In such cases it is suggested to generate a sweep endurance test procedure customized to the proving ground or actual roads. This paper studies a methodology for generating a sweep endurance test procedure for evaluation of resonating components. Responses like stress and accelerations were measured in test components in proving ground. Contribution of each frequency band towards overall damage is determined.