Response Sensitivity and Parameter Importance in Composites Manufacturing

In this article we derive, implement, and verify equations to compute the sensitivity of responses from numerical simulation of composites manufacturing. The responses considered are part temperature and degree of cure, as well as process-induced deformation of the cured part. The 'direct differentiation method' (DDM) is used, which entails a one-time investment of effort to differentiate the governing response equations analytically. The implementation of the derivative equations facilitates efficient and accurate computation of response sensitivities in all subsequent analyses. This article extends the DDM methodology developed earlier for mechanical problems. Novel 'shape sensitivity' equations and efficient implementation techniques are also included. In order to verify the implementations, the model predictions are compared with those obtained from the less efficient finite difference approach. A comprehensive example is presented where the usefulness and interpretation of response sensitivities are emphasized. It is observed that the responses are particularly sensitive to certain model parameters, for which further data gathering and model improvement efforts should be focused.