Heat transfer measurements on a turbine nozzle surface using liquid crystals

摘要

A high-performance cooling blade of a gas turbine is needed to provide acceptable metal temperatures and component life. So detailed and accurate heat transfer coefficients on these surfaces were needed. Thermochromic liquid crystals are suitable to clarify the outline of the heat transfer pattern on a plate as a blade surface. However, a data processing is needed for the quantitative measurement. We studied the quantitative measurement using a steady flow blowdown tunnel. We used an improved data processing method that is the LULICS{sup}1. The LITICS can relate rather wide-band crystal color to crystal temperature, so accurate heat transfer coefficients over the entire cascade surface are obtained using only one temperature-band liquid crystal. This paper describes an application of the LITICS in a steady flow blow-down tunnel and presents global maps of heat transfer coefficient on the semi-annular nozzle surfaces.