A Review of Exhaust Gas Temperature Sensing Techniques for Modern Turbine Engine Controls

Abstract

The exhaust gas temperature (EGT) is typically defined as the gas temperature at the exit of the turbine; the sensors used to measure this parameter are considered the most vulnerable elements of the entire turbine engine instrumentation. EGT measurement is considered a key parameter for optimizing fuel economy, diagnosis, and prognosis. The reason is that turbine blade temperature is a good indicator for normal life consumption of that blade. Currently, direct sensor measurements made on turbine modules are limited due to the extremely hot environment. Exhaust gas temperature (EGT) sensors located downstream from the highest temperature sections provide a means to roughly infer the temperatures seen by the turbine blades/disks. But these sensors, which themselves are subject to frequent failures, provide a fairly inaccurate indication of the actual metal temperature profiles. This is of particular importance for high performance military turbine engines where the margin between hot-section operating conditions and material limitations is shrinking. A future state is envisioned that would use emerging pyrometric, fiber optic, and laser-based sensing to accurately assess the condition and life usage of the hot section, on a blade-by-blade basis. Nomenclature= speed of sound = acoustic constant = distance between transceivers in acoustic pyrometer = molecular weight of the gas = gas pressure = universal gas constant = gas temperature = time of flight of acoustic signal in acoustic pyrometer = heat capacity ratio of the gas = gas density

Application of CNN-IndRNN model combined with residual structure in aircraft engine EGT prediction

“…Aircraft engines serve as the core systems of an aircraft, whose performance and reliability are crucial for flight safety [1][2]. Exhaust gas temperature (EGT) is an important performance indicator of aircraft engines, which can reflect the working and health status of the engine [3]. Accurate prediction of EGT is of great significance for the control and maintenance of the engine.…”

Error Estimation of Measured Exhaust Gas Temperature in Afterburner Mode in an Aero Gas Turbine Engine

“…As many parameters are involved in accurately predicting the emission coefficient of the target surface, it makes the measurement more complex and difficult 5 . Another non-contact method in high-temperature measurement is using TDLAS (Tunable Diode Laser Absorption Spectroscopy) which works on the principle of laser interferometry 6 . The associated measurement problems are laser noise, drifts, general interferometric effects, and stability problems.…”

Optimizing the Properties of La0.8Sr0.2CrO3 Thin Films through Post-Annealing for High-Temperature Sensing

“…In addition, its sensitivity is lower due to the small intrinsic Seebeck coefficients of noble metals. Therefore, the development of a new TFTC fabricated by conductive ceramics has been a trend to measure high temperatures in air [ 12 , 13 , 14 , 15 ]. Especially, conductive oxides with better oxidation resistance and higher Seebeck coefficients have become the most promising candidate materials of electrodes for TFTCs, such as In 2 O 3 , ITO, ZnO:Al (AZO), and La 1-x Sr x CrO 3 (xLSCO) [ 14 , 16 , 17 , 18 , 19 ].…”