Impact of plastic mechanical properties on modal prediction of optical module

摘要

Simulated modal analysis of a plastic part reinforced with fibers was made and compared to experimental modal analysis. Updating showed a much lower Young's modulus value and an inhomogeneous distribution of Young's modulus compared to initial hypothesis. Those updated results were compared to an injection simulation (MOLFLOW): injection analysis confirmed an inhomogeneous distribution of fibers and lower Young's modulus similar to the one achieved after updating. Vibration behavior using a Young's modulus distribution based on injection simulation was better correlated to measurement. Using that method on the optical module enables to reach a mode shape correlated with MAC >70% and frequency prediction within 10%.