Influence of Disturbing Factors in a System for Measuring Radial Clearances in Gas-Turbine Engines with Temperature Self-Compensation

Abstract

This paper presents the results of analysis of the effect of disturbing factors on changes in the informative parameter of a single-coil eddy-current sensor, which are used as input data in studies of a radial clearance measurement system with self-compensation of temperature effects on the sensor. Conversion functions of the measuring circuit with the connected single-coil eddy-current sensor are obtained in analytical form. The conversion functions are dependences of the extreme code values at the measuring circuit output on radial clearances and temperature effects on the sensor taking into account disturbing factors (adjacent blades, blade temperature, axial displacements of the gas turbine engine compressor rotor). Quantitative estimates are obtained for influence functions of these disturbing factors on the calculated difference of the extreme code values in the system, which characterizes the measured parameter.