Study On Pressure-Sensitive Paint Mearsurement Method For Application In Internal Flow Of Turbomachinery

Pressure-sensitive paint(PSP)is a kind of non-contact pressure measurement which has advantages of high spatial resolution and full field measurement when compared with traditional measurement and it has been widly used in aerodynamic measurement and analysis.For measuring internal flow of turbomachinery,optical window is needed when using traditional PSP measurement.However,it is always difficult to set an optical window because of the complexity of the turbomachinery structure and this greatly limits the application of PSP.In order to solve this problem,PSP measurement based on long afterglow method is proposed at first.This method combines long afterglow material and PSP to make a novel light-charge PSP,and uses light to excite the paint for charging light before measurement,then uses afterglow to excite PSP.It can realize PSP measurement with no outside light and significantly reduce demand of optical window in measurement setup.For some measurement environments with no optical window,PSP measurement based on endoscope method is further proposed in this paper.This method is to insert endoscope into the turobomachinery to take images of PSP signal,and develop another novel imprinted pattern PSP and a data processing method to get the full field surface pressure distribution.PSP images can be stitched based on imprinted random pattern,finally full field PSP image will be gotten.The two methods proposed in this parper not only solve the problem of internal pressure measurement of turbomachinery,but also extend the application and condition of PSP,laying a good foundation for the further development of test system.