Analytical method for turbine blade temperature mapping to estimate a pyrometer input signal

Abstract

The purpose of this thesis is to develop a method to estimate local blade temperatures in a gas turbine for comparison with the output signal of an experimental pyrometer. The goal of the method is to provide a temperature measurement benchmark based on a knowledge of blade geometry and engine operating conditions. A survey of currently available methods is discussed including both experimental and analytical techniques.The purpose of this thesis is to develop a method to estimate local blade temperatures in a gas turbine for comparison with the output signal of an experimental pyrometer. The goal of the method is to provide a temperature measurement benchmark based on a knowledge of blade geometry and engine operating conditions. A survey of currently available methods is discussed including both experimental and analytical techniques.

An analytical approach is presented as an example, using the output from a cascade flow solver to estimate local blade temperatures from local flow conditions. With the local blade temperatures, a grid is constructed which maps the temperatures onto the blade. A predicted pyrometer trace path is then used to interpolate temperature values from the grid, predicting the temperature history a pyrometer would record as the blade rotates through the pyrometer line of sight. Plotting the temperature history models a pyrometer input signal. An analytical approach is presented as an example, using the output from a cascade flow solver to estimate local blade temperatures from local flow conditions. With the local blade temperatures, a grid is constructed which maps the temperatures onto the blade. A predicted pyrometer trace path is then used to interpolate temperature values from the grid, predicting the temperature history a pyrometer would record as the blade rotates through the pyrometer line of sight. Plotting the temperature history models a pyrometer input signal.