Kasinathan, S., Gupta, S., Agha, H., and Modi, R., "Case Study: An Accelerated Methodology for Simulating Thermal Stress in Automotive Headlamps," SAE Technical Paper 2017-26-0322, 2017, doi:10.4271/2017-26-0322.
In any industry, early detection and mitigation of a failure in component is vital for feasible design changes or development iterations or saving money. So it becomes pivotal to capture the failure mode in an accelerated way. This theory poses many challenges in devising the methodology to validate the failure mode. In real world, vehicle head lamp is exposed to all possible kinds of harsh environments such as variable daily ambient, rain, dust and engine compartment temperature …etc. This brings rapid thermal stress onto headlamp resulting into warpage cracks. At vehicle level on particular model, this failure is typically observed after 20,000-25,000 kms in a span of 3-4 months of running. Any corrective action to revalidate the design change or improvement will need similar timelines in regular way to test, which is quite high in product development cycle. In this paper, we emphasize on accelerated test cycle to generate the failure mode within 12-15days on vehicle level test and 4-5 days on bench level test. To derive the test cycles, fishbone diagram, thermal mapping, energy consumption, and onroad illumination data implied effectively.