Measurement Of Exhaust Gas Temperature Research Articles

Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines: Part II Unsteady processes

Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines: Part II Unsteady processes The second part of the article presents the results of operating diagnostic tests of a two- and three-shaft engine with a separate power turbine during the start-up and acceleration of the rotor units. Attention was paid to key importance of the correctness of operation of the automatic engine load control system, the input for which, among other signals, is the rate of increase of the exhaust gas flow temperature. The article presents sample damages of the engine flow section which resulted from disturbed functioning of this system. The unsteady operation of the compressor during engine acceleration was the source of excessive increase of the exhaust gas temperature behind the combustion chamber and partial burning of the turbine blade tips.

Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines

Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines The third part of the article presents a method for detecting failures of the automatic engine control system with the aid of an exhaust gas temperature setter, specially designed and machined for this purpose. It also presents a procedure of identifying the operating tolerances and determining the diagnostic tolerances for the exhaust gas temperature recorded in the naval turbine engine during the start-up and acceleration processes. The diagnostic tolerances were determined using the statistic inference, based on the hypothesis about the normal distribution of the starting exhaust gas temperature dispersion at the initial time of engine operation. The above hypothesis was verified using the non-parametric statistic test χ2 for examining the consistency of the empirical distribution with the assumed normal distribution. As a result of the examination, satisfactory convergence of the compared distributions was obtained which made the basis for assuming the three-sigma limits of the diagnostic tolerance for the analysed engine control parameter.

Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines

Exhaust gas temperature measurements in diagnostic examination of naval gas turbine enginesThe first part of the article is limited to the presentation of the results of diagnostic examination of a three-shaft engine with a separate power turbine, operating in steady-load states. The here presented diagnostic analyses and syntheses based on a simplified mathematical model of thermal and flow processes taking place in the combustion chamber, which was used for deriving the equation describing the average steady-state temperature of the exhaust gas flow at the outlet cross-section of the chamber.

Optimization of a tracer-based PLIF diagnostic for simultaneous imaging of EGR and temperature in IC engines

A tracer-based planar laser-induced fluorescence (TB-PLIF) imaging diagnostic using 3-pentanone has been optimized for use in IC engines. The diagnostic utilizes dual-wavelength excitation of 3-pentanone in the ultraviolet to make simultaneous measurements of exhaust gas residual mole fraction and temperature. A merit function based optimization of the diagnostic precision was performed which allowed for selection of optimal excitation wavelengths for the conditions of interest. Optimized system performance was validated in a motored optical engine over a wide range of in-cylinder temperatures and pressures. In-cylinder results verify the utility of the uncertainty estimates. Differences in magnitude between the estimated and measured precision were determined to be due to errors in parameter values used in the calculations. The observed 2.1% temperature precision at a temperature of 600 K was compared with previous TB-PLIF temperature measurements and shown to be approximately a factor of 2 better than previous results.

BUTANOL—A SINGLE CYLINDER ENGINE STUDY: ENGINE PERFORMANCE

The effect of methanol and butanol addition to gasoline on brake specific fuel consumption (b.s.f.c.), exhaust gas temperature, and thermal efficiency has been experimentally investigated. A Hydra single cylinder, spark ignition, fuel injection engine was used over a wide range of fuel/air equivalence ratio (ϕ=0⋅8 to 1⋅3) for 30% volume alcohol–gasoline blends. The goal of this work is to study the engine performance when methanol and butanol–gasoline blends are used. The performance measurements show that there is an increase in b.s.f.c. when using alcohol–gasoline blends, and b.s.f.c. of a butanol–gasoline blend is less than for a methanol–gasoline blend. The experimental results show that the engine thermal efficiency was decreased when fueled with alcohol–gasoline blends. It was found that there was about a 4.5% reduction in engine thermal efficiency at ϕ=1⋅0 when 30% butanol was blended with gasoline compared to pure gasoline. The exhaust gas temperature measurements show that there is an increase in temperature in the case of using gasoline as compared to alcohol–gasoline blends, and that the temperature reaches a maximum at ϕ≈1⋅1 when using gasoline and alcohol–gasoline blends. © 1997 by John Wiley & Sons, Ltd.

A method for testing the flammability of sprays of hydraulic fluid

A method for testing the flammability hazards of hydraulic fluids in the form of spray escapes, is described. The method utilizes sprays, produced by a twin-fluid atomizer, which are ignited at their roots by the carefully controlled input of heat from a gas flame. This heat input is sufficient to provide complete combustion of highly flammable fluids, such as mineral oils, but increasingly incomplete combustion for increasingly less flammable fluids. Measurements of exhaust gas temperature, flame length and particulate emissions are made to derive three separate hazard rankings of fluids. The same test may be extended to rank fluids using other parameters, such as luminosity and exhaust toxicity. The exhaust gas temperature, when suitably normalized, provides the basic hazard ranking parameter, the ‘ignitability’, which provides a measure of the ease of igniting and stabilizing a spray flame of the fluid. A wide range of fluids has been investigated by using the new testing method and the resulting rankings are consistent with qualitative expectations. The technique provides a continuous ranking scale which gives a clear and repetitive means of comparing different fluids. The flammability testing apparatus incorporates careful control and measurement of all flow rates and a compact combustion chamber, with a co-flowing airflow around the spray which removes problems due to a poorly controlled environment which have occurred in earlier tests.

Indirect Evaluation of the Torque of Diesel Engines

ABSTRACT THE torque of diesel engines is evaluated indirectly by three methods proposed from data obtained in performance tests in the power take-off of tractors: measurement of the fuel consumption, measurement of exhaust gas temperature and measurement of the engine governor control lever position. A statistical analysis of the results indicated that in the mathematical correlation, for all methods, the engine speed should be included as an additional independent variable. Considerations were made regarding the utilization of each method as function of accuracy, costs and adaptability

Tractor Monitor Based on Indirect Fuel Measurement

ABSTRACT AN indirect method of indicating tractor fuel consumption by measurement of exhaust gas temperature is described. The signal from the exhaust temperature is combined with that from a fifth wheel to provide an output proportional to instantaneous fuel consumption in terms of litres per hectare.

Rate of heat release measurements with the Swedish box test

AbstractThe Swedisn box apparatus was modified to include an oxygen analysis of the exhaust gases to be compared with the conventional exhaust gas temperature measurement. A slow‐burning material shows good correlation between the temperature measurement and the rate of heat release. A fast‐burning material, however, consumes all the available oxygen, and the temperature measurement becomes a measure of only the thermal properties of the material.

Calorimetric Microwave Loss Measurements of Granular Materials

AbstractDirect calorimetric evaluation of the microwave loss of dielectrics is possible for granular materials. A cylindrical sample is heated by the microwave field of an incident wave in a rectangular guide and simultaneously cooled by a gas flowing through the bed.A mathematical model describing the energy balance and the heat transfer between the microwaves, the materials and the gas is proposed. It is shown that it is possible to determine, simultaneously, the temperature of the material and its microwave dielectric loss from the measurement of the exhaust gas temperature when thermal equilibrium occurs.

舶用ディーゼル機関の排気温度計の指示値に関する研究

In the marine Diesel engine, there still remains problems about the relation between thermal loads of engines and the indicated values of thermometer. Therefore, the exact measurement of exhaust gas temperature has expected up to the present. The indicated value is mainly affected by two factors which are the measurement factors of exhaust gas temperature and the gas flow in the exhaust pipe, and it is still not clear how these two factors affect the indicated value.In this study the measurement factors affecting on the indicated value were examined, using two kinds of steady state exhaust gases in the duct and the thermometer well which was filled several thermocouples up the axial surface. Owing to the results, the temperature of the tip of well usually is different from gas temperature, even if the longitudinal length of well takes enough. Therefore, it seems that it is not suitable to make the reading gas temperature, the correcting of the reading is necessary to take account thermal characteristics of well in the duct.

Measurement of High Temperatures in High-Velocity Gas Streams

Abstract Conventional methods of measuring temperatures are subject to considerable errors, when applied to gas streams at velocities around 500 fps and temperatures of the order of 1600 F, which conditions occur, for example, in the exhaust-gas pipe of an airplane engine. An investigation of this problem the results of which are reported in this paper was suggested by the Special Subcommittee on Exhaust Gas Turbines and Intercoolers of the N.A.C.A. and was carried out with the assistance of the Subcommittee on Exhaust Gas Temperature Measurement of the Committee on Industrial Instruments and Regulators. Tests were conducted on the thermocouple, which at present is the most satisfactory temperature-measuring device available, to develop a shield and mounting that would achieve maximum accuracy and minimum size and weight for airplane application. The results indicate that something better than the ordinary thermocouple mountings is required for even a fair degree of accuracy with either the high velocities or temperatures considered. A few tentative devices are suggested which will serve until further studies have been made and more adequate solutions provided.