Design Parameters for an Aircraft Engine Exit Plane Particle Sampling System

Author(s):  
Hsi-Wu Wong ◽  
Zhenhong Yu ◽  
Michael T. Timko ◽  
Scott C. Herndon ◽  
Elena de la Rosa Blanco ◽  
...  

The experimental data and numerical modeling were utilized to investigate the effects of exhaust sampling parameters on the measurements of particulate matter (PM) emitted at the exit plane of gas-turbine engines. The results provide guidance for sampling system design and operation. Engine power level is the most critical factor that influences the size and quantity of black carbon soot particles emitted from gas-turbine engines and must be considered in sampling system design. The results of this investigation indicate that the available soot surface area significantly affects the amount of volatile gases that can condense onto soot particles. During exhaust particle measurements, a dilution gas is typically added to the sampled exhaust stream to suppress volatile particle formation in the sampling line. Modeling results indicate that the dilution gas should be introduced upstream before a critical location in the sampling line that corresponds to the onset of particle formation microphysics. Also, the dilution gas should be dry for maximum nucleation suppression. In most aircraft PM emissions measurements, the probe-rake systems are water cooled and the sampling line may be heated. Modeling results suggest that the water cooling of the probe tip should be limited to avoid overcooling the sampling line wall temperature and, thus, minimize additional particle formation in the sampling line. The experimental data show that heating the sampling lines will decrease black carbon and sulfate PM mass and increase organic PM mass reaching the instruments. Sampling line transmission losses may prevent some of the particles emitted at the engine exit plane from reaching the instruments, especially particles that are smaller in size. Modeling results suggest that homogeneous nucleation can occur in the engine exit plane sampling line. If newly nucleated particles, typically smaller than 10 nm, are indeed formed in the sampling line, sampling line particle losses provide a possible explanation, in addition to the application of dry diluent, that they are generally not observed in the PM emissions measurements.

2014 ◽  
Vol 900 ◽  
pp. 773-776
Author(s):  
Yu Yu Zuo

There are many reasons for having a lubricant within the engine besides that of reducing friction. However scrupulously clean the engine is maintained, there will always be a small amount of dirt or impurities that find their way inside. That dirt must be removed before it can cause damage to bearings or block small oil passageways. The oil can be used to keep the engine clean by carrying dirt to the oil filter where it is strained out and where it remains until replacement of the filter. The majority of the bearings within the engine are manufactured from steel, a metal which would soon oxidize itself if it were not prevented from doing so by a liberal coating of oil, thus the lubricant will also minimise corrosion inside the engine.


2019 ◽  
Vol 62 (2) ◽  
pp. 298-303
Author(s):  
A. V. Il’inkov ◽  
A. M. Ermakov ◽  
V. V. Takmovtsev ◽  
A. V. Shchukin ◽  
A. M. Erzikov

Author(s):  
G. J. Sturgess ◽  
D. Shouse

The U.S. Air Force is conducting a comprehensive research program aimed at improving the design and analysis capabilities for flame stability and lean blowout in the combustors of aircraft gas turbine engines. As part of this program, a simplified version of a generic gas turbine combustor is used. The intent is to provide an experimental data base against which lean blowout modeling might be evaluated and calibrated. The design features of the combustor and its instrumentation are highlighted, and the test facility is described. Lean blowout results for gaseous propane fuel are presented over a range of operating conditions at three different dome flow splits. Comparison of results with those of a simplified research combustor is also made. Lean blowout behavior is complex, so that simple phenomenological correlations of experimental data will not be general enough for use as design tools.


Author(s):  
Gerald J. Micklow ◽  
Krishna Ankem ◽  
Tarek Abdel-Salam

Understanding the physics and chemistry involved in spray combustion, with its transient effects and the inhomogeneity of the spray is quite challenging. For efficient operation of both internal combustion and gas turbine engines, great insight into the physics of the problem can be obtained when a computational analysis is used in conjunction with either an experimental program or through published experimental data. The main area to be investigated to obtain good combustion begins with the fuel injection process and an accurate description of the mean diameter of the fuel particle, injection pressure, drag coefficient, rate shaping etc must be defined correctly. This work presents a methodology to perform the task set out in the previous paragraph and uses experimental data obtained from available literature to construct a semi-empirical numerical model for high pressure fuel injectors. A modified version of a multidimensional computer code called KIVA3V was used for the computations, with improved sub-models for mean droplet diameter, injection pressure, injection velocity, and drop distortion and drag. The results achieved show good agreement with the published in-cylinder experimental data for a Volkswagen 1.9 L turbo-charged direct injection internal combustion engine under actual operating conditions. It is crucial to model the spray distribution accurately, as the combustion process and the resulting temperature distribution and pollutant emission formation is intimately tied to the in-cylinder fuel distribution. The present scheme has achieved excellent agreement with published experimental data and will make an important contribution to the numerical simulation of the combustion process and pollutant emission formation in compression ignition direct injection engines and gas turbine engines.


Author(s):  
Christopher J. Spytek

An on demand oil system, based on electrically driven lube and scavenge pumps, for use in gas turbine engines has been developed. The need to optimize gas turbine engine performance, coupled with ‘electrification’ of aircraft systems, as on the Lockheed F35 and Boeing 787 in order to maximize efficiency and flexibility, created an opportunity to develop a ‘smart’ electrically driven lubrication system for gas turbine engines. Spytek’s electric oil system, developed for use on its 400lbt ATG-2 engine platform, ascertains the operating condition of the gas turbine engine, including speed, pressure, bearing temperatures and determines the amount of lubrication required for each bearing zone. The system has the benefit of better thermal control of engine bearings, lower system weight and power use, with flexibility in the placement of the system on the engine/airframe combination. The system has been successfully demonstrated on the Spytek Aerospace ATG-2/J304 gas turbine engine series. Major areas addressed in the development of the system were the selection of reliable, gas turbine engine compatible feed and scavenge pumps, control systems sensoring and feedback, variable feed of oil to the individual sump wells, as well as systems durability and operating parameters. Various gas turbine engine platforms can require altered oil system duty cycles, including pre-oiling or post run down-oiling, high flow oil conditions, features not readily available in traditional mechanical systems but easily implemented using the Spytek on-demand oil system. In the project effort, evaluation of the existing prototype system was used as a system design baseline. Data on pump wear, filter performance and oil supply degradation was available and used in refining the oil system design. The ATG-2 system was modified to take advantage of a full proportional integral derivative controlled oil system with system demonstrations made on a gas turbine engine, demonstrating oil supply on demand capability and full bearing thermal management system control.


Author(s):  
Pravin Nakod ◽  
Sourabh Shrivastava ◽  
Saurabh Patwardhan ◽  
Stefano Orsino ◽  
Rakesh Yadav

Abstract Low emission gas turbine engines, operating under fuel lean conditions, are susceptible to light-around issues. Traditionally, gas turbine manufacturers rely on experimentation and testing to understand the relight characteristics of a combustor. However, since the last decade, numerical simulations are gaining popularity in performance evaluation of the light-around characteristics of the gas turbine combustors. In the present work, assessment of the Flamelet Generated Manifold (FGM) combustion model is carried out to understand its performance for capturing the correct ignition sequence in a linear multi-burner methane-air swirl combustor designed by COmplexe de Recherche Interprof essionnel en Aérothermochimie (CORIA) in the context of Knowledge for Ignition, Acoustics, and Instabilities (KIAI) project. The present work uses linear five, four and two swirled injector configurations for the validation of the simulation results. Non-reacting and reacting Large Eddy Simulations (LES) are performed for three injector arrangements to predict the main flow structure, mixing, flame propagation and ignition sequence. Non-reacting time-averaged flow quantities such as mean axial and radial velocities are data-sampled and compared with the experimental results. The predicted results show a good comparison between simulation and experimental data. Ignition sequence and timing predicted from the reacting LES for all the three configurations studied in this work, also compare well with the experimental data. This numerical investigation confirms that the FGM combustion model used in the LES framework can be successfully employed for the prediction of the relight characteristics of the gas turbine engines.


Author(s):  
Szymon Fulara ◽  
Maciej Chmielewski ◽  
Marian Gieras

The main aim of this article is to present the experimental data of the operating parameters and emissions obtained in a small gas turbine equipped with a variable area nozzle system. The variable area nozzle is proposed as a means of improving turbine efficiency, which has been a popular trend in recent development of gas turbine engines. Based on turbine vane twisting, the proposed variable area nozzle system was developed and implemented in GTM-120 small gas turbine. The concept was experimentally investigated on the engine test bench and engine working parameters were accurately measured. Experimental research shows that significant improvement of engine specific fuel consumption (up to 4%) and specific thrust (up to 5%) has been achieved. Additionally, reduction in CO emissions (up to 64%), NO emissions (up to 7%) and NO2 emissions (up to 53%) has been noted. Experimental research results were compared with analytical engine model showing moderate, qualitative agreement between the experimental data and model outputs. Main advantages of variable area nozzle system and design challenges of the proposed concept are discussed in the article summary.


2021 ◽  
Vol 4 (8(112)) ◽  
pp. 59-66
Author(s):  
Ludmila Boyko ◽  
Vadym Datsenko ◽  
Aleksandr Dyomin ◽  
Nataliya Pizhankova

The design and adjustment of modern gas turbine engines significantly rely on the use of numerical research methods. This paper reports a method devised for calculating the thermogasdynamic parameters and characteristics of a turboshaft gas turbine engine. The special feature of a given method is a two-dimensional blade-by-blade description of the compressor in the engine system. Underlying the calculation method is a nonlinear mathematical model that makes it possible to describe the established processes occurring in individual nodes and in the engine in general. To build a mathematical model, a modular principle was chosen, involving the construction of a system of interrelated and coordinated models of nodes and their elements. The approach used in modeling a two-dimensional flow in the compressor makes it possible to estimate by calculation a significant number of parameters that characterize its operation. With the help of the reported method, it is possible to estimate the effect of changing the geometric parameters of the compressor height on the characteristics of the engine. To take into consideration the influence of variable modes of air intake or overflow in various cross-sections along the compressor tract, to determine the effect of the input radial unevenness on the parameters of the compressor and engine in general. To verify the method described, the calculation of thermogasdynamic parameters and throttle characteristics of a single-stage turboshaft gas turbine engine with a 12-stage axial compressor was performed. Comparison of the calculation results with experimental data showed satisfactory convergence. Thus, the standard deviation of the calculation results from the experimental data is 0.45 % for the compressor characteristics, 0.4 % for power, and 0.15 % for specific fuel consumption. Development and improvement of methods for calculating the parameters and characteristics of gas turbine engines make it possible to improve the quality of design and competitiveness of locally-made aircraft engines.


1997 ◽  
Vol 119 (1) ◽  
pp. 108-118 ◽  
Author(s):  
G. J. Sturgess ◽  
D. Shouse

The U. S. Air Force is conducting a comprehensive research program aimed at improving the design and analysis capabilities for flame stability and lean blowout in the combustors of aircraft gas turbine engines. As part of this program, a simplified version of a generic gas turbine combustor is used. The intent is to provide an experimental data base against which lean blowout modeling might be evaluated and calibrated. The design features of the combustor and its instrumentation are highlighted, and the test facility is described. Lean blowout results for gaseous propane fuel are presented over a range of operating conditions at three different dome flow splits. Comparison of results with those of a simplified research combustor is also made. Lean blowout behavior is complex, so that simple phenomenological correlations of experimental data will not be general enough for use as design tools.


Sign in / Sign up

Export Citation Format

Share Document