Evaluating Thermographic Phosphors in an Operating Turbine Engine

Abstract

The results of a field test in a commercial turbine engine showed that we can remotely measure the temperature of engine components in operating engines using thermographic phosphors. The remote-measurement method exploits the temperature dependence of the characteristic decay time of the laser-induced fluorescence of thermographic phosphors. This paper summarizes recent work leading up to and including a successful test of the thermographic-phosphor method in an operating turbine engine.

An analysis of Y2O3:Eu3+ thin films for thermographic phosphor applications

“…Thermographic phosphors are materials whose luminescent properties, such as the fluorescent decay time, intensity, breadth and position are all sensitive to changes in temperatures and change predictably with temperature [1,[7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]. The luminescent properties are influenced by changes in the ligand field surrounding the fluorescing ion with temperature.…”

A review of some current research on pressure sensitive paint and thermographic phosphor techniques

“…The TP layers must also be durable. The most widely used techniques for bonding thermographic phosphors based systems to surfaces are (14) :…”

Simultaneous phosphor and CARS thermometry at the wall–gas interface within a combustor

“…Therefore, the temperature of phosphor-coated surfaces can be determined by measuring their luminescence properties after laser excitation. In combustion applications, surface thermometry based on TPs has been used in static [2][3][4][5] or moving systems [6]. In contrast to other phosphors, the decay time of Mg 4 FGeO 6 :Mn is not influenced by oxygen quenching or varying absolute pressure [7].…”