THIN-FILM THERMOCOUPLES FOR LOCALIZED HEAT-TRANSFER MEASUREMENTS

This paper describes a proof-of-concept experiment on thin-film thermo couples used for localized heat transfer measurements applicable to ex periments in warm turbine testing, Using thin-film thermocouples to me asure turbine blade temperatures and heat transfer will noticeably imp rove the accuracy of the acquired data because the current method of e mbedded conventional thermocouples introduces large experimental uncer tainty, First, we introduce the thin-film sensors and manufacturing pr ocedures. Attention is paid to connections between thin-film thermocou ples and lead wires, which have been a source of problems in the past, Then, we discuss the test arrangement and facility used for the heat transfer measurements, Finally, we present the results of bulk and loc al heat flux measurements, as well as overall heat transfer coefficien ts obtained from measurements in a narrow passage with an AR of 11.8. Experimental data acquired from thin-film thermocouples and their tren ds agree very well with data acquired using conventional thermocouples . The results we obtained establish confidence about using thin-film t hermocouples for heat transfer measurements in warm turbine testing.