PHOTOTHERMOELASTIC EXPERIMENTAL INVESTIGATION OF TURBINE DISK

This paper deals with three aspects of photothermoelastic study of the steady thermal stress field on the turbine disk.First of all,the test methods and techniques are investigated. It is necessary to select a suitable model material which will not change mechanical and optical properties within the range of test temperature. In this experiment the epoxy resin is adopted. Then, it is imperative to determine measuring and recording methods oftemperature and to research heating and controlling techniques of temperature field.In this case, the surface of outer edge of the disk is wrapped with heating tapewhich is a polyester film coated by carbon. The temperatures of the model are measured with thermocouples EA2 embedded in the surface or indepth of the model, and are autocontrolled.Secondly, the photothermoelastic experiment and theoretical calculation of aplane disk have been carried out. Both results of experiment and calculation are ingood agreement. It is proved that the methods and techniques proposed can be usefulfor practice.Thirdly, the photothermoelasticity model test of a turbine disk has been completed. The data of the test can be used as a reference for turbine disk design.