Aerospace applications of luminescent paint

Abstract

AbstractA heat transfer measurement technique has been developed, which utilised a laser to heat a spot of the ‘standard’ luminescent paint on an insulated metal wind tunnel model. The convective heat transfer coefficient was determined from the experimental quasi steady-state surface temperature, and solutions obtained from radial and axial conduction in a numerical heat transfer model. The convective heat transfer coefficient variation over both a flat plate and a NACA 0012 aerofoil have been measured in transonic flow. Measurements obtained from the flat plate were seen to agree well with correlation data from the literature. Measurements on the NACA 0012 aerofoil indicated the point of transition from laminar to turbulent boundary layer as well as the location of shock boundary layer interaction. The luminescent paint provided simultaneous measurements of pressure and temperature (see Part 1). The distribution of pressure over the NACA 0012 aerofoil was shown to be in excellent agreement with conventional transducer data, although the luminescent paint data provided greater spatial resolution. The position of the shock determined from the heat transfer measurements was shown to be in excellent agreement with the pressure measurements.