Measurement of stresses in a vibrating polymeric film

Abstract

One dimensional model for the investigation of longitudinal vibrations of polymeric film is investigated. Comparison of stroboscopic and time averaged intensities in the photo‑elastic images is performed. Results about the required number of images for performing time averaging are provided. Recommendations for simultaneous application of both stroboscopic and time averaged photo‑elasticity for measurement of stresses are given. One dimensional model for the investigation of vibrations of polymeric film having two nodal degrees of freedom (longitudinal displacement and displacement of the upper surface, assuming that displacement of the lower surface is of the same value but in the opposite direction) is investigated. This model is applied for the interpretation of results of thermo‑elastic analysis. Recommendations for the interpretation of the stress field by using photo‑elastic and thermo‑elastic methods are provided.