scholarly journals МЕТОД РАСЧЕТА ТЕРМОГАЗОДИНАМИЧЕСКИХ ПАРАМЕТРОВ ТУРБОВАЛЬНОГО ГТД НА ОСНОВЕ ПОВЕНЦОВОГО ОПИСАНИЯ ЛОПАТОЧНЫХ МАШИН. ЧАСТЬ 1. ОСНОВНЫЕ УРАВНЕНИЯ

2018 ◽  
pp. 48-58
Author(s):  
Людмила Георгиевна Бойко ◽  
Олег Владимирович Кислов ◽  
Наталия Владимировна Пижанкова
Keyword(s):  
Gas Turbine ◽  
Flow Rate ◽  
Pressure Ratio ◽  
Turbine Engines ◽  
Geometrical Parameters ◽  
Gas Turbine Engines ◽  
Balance Equations ◽  
Wide Range ◽  
In Series ◽  
Multistage Compressor

Gas turbine engines processes mathematic simulations are widely used in different steps of its living cycle. All engine simulations may be divided into different difficulty levels: higher simulation level allows doing a more pre­cise description of physical processes in main units of gas turbine engines and their elements. It gives the oppor­tunity for getting better arrangement of calculation results and experimental data, reduce the quality of factors, which are traditionally used in determine engine operational characteristics with 1-level models.The purpose of the article is to describe the thermogasdynamic parameters and maintenance perfomances cal­culation method, which based on second level mathematic simulation. Its main feature is blade-to-blade turbomachines description (multistage compressor and multistage cooling gas turbine), which allows to take into account blade and flow path geometrical parameters. Their changing during the gas turbine engine design and de­velopment processes influence its performances: thrust, fuel consumption, efficiency as functions of values of flow rate, rotational speed, engine entrance conditions and so on. All these dependences could be defined by using proposed calculation method.In distinction from methods which are noted, this method allows to concede compressor or turbine incidence angles, drag values, pressure ratio, surge margin in design and off-design  engine regimes. The opportunity to take into account by-passing and air bleeding from compressor blade channels and their engine parameters influence is very important also.The article includes calculation method main points, block-scheme, equations system, which gives the opportunity of alignment the engine units and their elements in wide range of state working regimes. Set of equations consists of flow rate balance equations through the stages of multistage compressor and turbine, combustion chamber and connected channels. Also system includes power balance equations, by-passing, air bleeding from compressor stages channels, its admission into the cooling turbine stages and ac­counts their thermodynamic parameters. Compressors and turbines maps parameters are calculated with main turbomachinery theory lows and semi-empirical dependences.This article is the first in series of articles, which considers this problem

The Effects of Ambient Conditions on Gas Turbine Emissions—Generalized Correction Factors

1978 ◽  
Vol 100 (4) ◽  
pp. 640-646 ◽  
Author(s):  
P. Donovan ◽  
T. Cackette
Keyword(s):  
Gas Turbine ◽  
Pressure Ratio ◽  
Turbine Engines ◽  
Inlet Temperature ◽  
Gas Turbine Engines ◽  
Correction Factors ◽  
Oxides Of Nitrogen ◽  
Ambient Conditions ◽  
Nitrogen Emission ◽  
Wide Range

A set of factors which reduces the variability due to ambient conditions of the hydrocarbon, carbon monoxide, and oxides of nitrogen emission indices has been developed. These factors can be used to correct an emission index to reference day ambient conditions. The correction factors, which vary with engine rated pressure ratio for NOx and idle pressure ratio for HC and CO, can be applied to a wide range of current technology gas turbine engines. The factors are a function of only the combustor inlet temperature and ambient humidity.

scholarly journals ВПЛИВ ГУСТОТИ РЕШІТКИ НА АЕРОДИНАМІЧНУ НАВАНТАЖЕНІСТЬ РОБОЧОГО КОЛЕСА ОСЬОВОГО ВЕНТИЛЯТОРА

2020 ◽  
pp. 38-43
Author(s):  
Екатерина Викторовна Дорошенко ◽  
Михаил Владимирович Хижняк ◽  
Юрий Матвеевич Терещенко
Keyword(s):  
Gas Turbine ◽  
Pressure Ratio ◽  
Turbine Engines ◽  
Average Radius ◽  
Gas Turbine Engines ◽  
Axial Fan ◽  
Aerodynamic Loading ◽  
Wide Range ◽  
Axial Fans ◽  
Bypass Ratio

The main requirements that apply to axial fans and axial compressors of aircraft gas turbine engines include minimum dimensions and weight; high aerodynamic load; high coefficient of performance; wide range of steady work; high reliability. For gas turbine engines, the requirements of minimum weight and dimensions are especially important, since the engines must provide flights at high velocities and altitudes. This study aims to assess the effect of the solidity of the impeller fan on the average radius on the aerodynamic loading of the impeller of an axial fan for an engine with a high bypass ratio. The object of the study is the impeller of the fan. The solidity of the impeller fan on the average radius varied in the range from 1.8 to 0.82, the number of blades of the impeller fan varied from 33 to 15, respectively. The studies in this work were carried out by the method of numerical experiment. The flow in the axial fans was simulated by solving the system of Navier-Stokes equations, which were closed by the SST turbulent viscosity model. Based on the analysis of the results of the study, an assessment is made of the influence of the solidity of the impeller fan at an average radius on the aerodynamic loading of the impeller of an axial fan for an engine with a high bypass ratio. The research results showed that with a decrease in the solidity of the impeller fan at an average radius of 1.8 to 0.82 in operating modes with an axial inlet velocity of 80 to 120 m / s, the impeller fan pressure ratio decreases by 0.11 ... 3.2 %. The maximum decrease in the fan pressure ratio increase for the fan impeller with the parameters studied is 3.2 %, with a decrease in the number of fan blades from 33 to 15, while the total weight of the blades decreases by 54.55 %. The decrease in the solidity on the average radius of the impeller of the studied fan leads to a decrease in the relative sizes of the low-velocity zones at the sleeve and on the periphery and to a decrease in the level of flow unevenness. A further reduction in the level of flow non-uniformity behind the fan is possible when using the boundary layer control in the fan - this is the task of subsequent studies.

Enhanced Design of Cross-Flow Microchannel Heat Exchanger Module for High-Performance Aircraft Gas Turbine Engines

2012 ◽  
Vol 134 (6) ◽  
Author(s):  
Brittany Northcutt ◽  
Issam Mudawar
Keyword(s):  
Gas Turbine ◽  
Heat Exchangers ◽  
High Performance ◽  
Pressure Ratio ◽  
Cross Flow ◽  
Turbine Engines ◽  
Geometrical Parameters ◽  
Gas Turbine Engines ◽  
Aircraft Fuel ◽  
High Performance Aircraft

This study explores the design of highly compact air–fuel heat exchangers for high-performance aircraft turbine engines. The heat exchangers consist of a large number of modules that can be brazed together into a rectangular or annular outer envelope. Inside the module, fuel flows through parallel microchannels, while air flows externally perpendicular to the direction of the fuel flow over rows of short, straight fins. A theoretical model recently developed by the authors for a single module is both validated experimentally, by simulating aircraft fuel with water, and expanded to actual heat exchangers and JP-8 aircraft fuel. An optimization study of the module’s geometrical parameters is conducted for high-pressure-ratio engine conditions in pursuit of the highest heat transfer rate. These parameters are then adjusted based on such considerations as microfabrication limits, stress and rupture, and the need to preclude clogging of the fuel and air passage. Using the revised parameters, the analytical model is used to generate effectiveness plots for both rectangular and annular heat exchangers with one air pass and one, two, or three fuel passes. These results demonstrate both the effectiveness of the module design and the versatility of the analytical tools at designing complex heat exchangers for high-performance aircraft gas turbine engines.

Design, Development and Application of Vehicle Gas Turbine Engines

1966 ◽  
Vol 181 (1) ◽  
pp. 149-172
Author(s):  
P. A. Phillips ◽  
Peter Spear
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Low Cost ◽  
Engine Performance ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Design Development ◽  
Turbine Engine ◽  
Wide Range ◽  
Cycle Temperature

After briefly summarizing worldwide automotive gas turbine activity, the paper analyses the power plant requirements of a wide range of vehicle applications in order to formulate the design criteria for acceptable vehicle gas turbines. Ample data are available on the thermodynamic merits of various gas turbine cycles; however, the low cost of its piston engine competitor tends to eliminate all but the simplest cycles from vehicle gas turbine considerations. In order to improve the part load fuel economy, some complexity is inevitable, but this is limited to the addition of a glass ceramic regenerator in the 150 b.h.p. engine which is described in some detail. The alternative further complications necessary to achieve satisfactory vehicle response at various power/weight ratios are examined. Further improvement in engine performance will come by increasing the maximum cycle temperature. This can be achieved at lower cost by the extension of the use of ceramics. The paper is intended to stimulate the design application of the gas turbine engine.

Thermo-Economic Optimization in the Design of Small-Scale and Residential Cogeneration Systems

2009 ◽  
Author(s):  
C. P. Lea˜o ◽  
S. F. C. F. Teixeira ◽  
A. M. Silva ◽  
M. L. Nunes ◽  
L. A. S. B. Martins
Keyword(s):  
Gas Turbine ◽  
Urban Areas ◽  
Pressure Ratio ◽  
Optimization Method ◽  
Turbine Engines ◽  
Small Scale ◽  
Inlet Temperature ◽  
Gas Turbine Engines ◽  
Economic Optimization ◽  
Micro Turbine

In recent years, gas-turbine engines have undergone major improvements both in efficiency and cost reductions. Several inexpensive models are available in the range of 30 to 250 kWe, with electrical efficiencies already approaching 30%, due to the use of a basic air-compressor associated to an internal air pre-heater. Gas-turbine engines offer significant advantages over Diesel or IC engines, particularly when Natural Gas (NG) is used as fuel. With the current market trends toward Distributed Generation (DG) and the increased substitution of boilers by NG-fuelled cogeneration installations for CO2 emissions reduction, small-scale gas turbine units can be the ideal solution for energy systems located in urban areas. A numerical optimization method was applied to a small-scale unit delivering 100 kW of power and 0.86 kg/s of water, heated from 318 to 353K. In this academic study, the unit is based on a micro gas-turbine and includes an internal pre-heater, typical of these low pressure-ratio turbines, and an external heat recovery system. The problem was formulated as a non-linear optimisation model with the minimisation of costs subject to the physical and thermodynamic constraints. Despite difficulties in obtaining data for some of the components cost-equations, the preliminary results indicate that the optimal compressor pressure ratio is about half of the usual values found in large installations, but higher than those of the currently available micro-turbine models, while the turbine inlet temperature remains virtually unchanged.

Design Study of an Advanced Concept Simple Gas Turbine for Possible Use in Low Emission Automobiles

1972 ◽  
Author(s):  
H. C. Eatock ◽  
M. D. Stoten
Keyword(s):  
High Pressure ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Simple Cycle ◽  
Turbine Engines ◽  
Nox Emissions ◽  
Preliminary Design ◽  
Gas Turbine Engines ◽  
High Pressure Ratio

United Aircraft Corporation studied the potential costs of various possible gas turbine engines which might be used to reduce automobile exhaust emissions. As part of that study, United Aircraft of Canada undertook the preliminary design and performance analysis of high-pressure-ratio nonregenerated (simple cycle) gas turbine engines. For the first time, high levels of single-stage component efficiency are available extending from a pressure ratio less than 4 up to 10 or 12 to 1. As a result, the study showed that the simple-cycle engine may provide satisfactory running costs with significantly lower manufacturing costs and NOx emissions than a regenerated engine. In this paper some features of the preliminary design of both single-shaft and a free power turbine version of this engine are examined. The major component technology assumptions, in particular the high pressure ratio centrifugal compressor, employed for performance extrapolation are explained and compared with current technology. The potential low NOx emissions of the simple-cycle gas turbine compared to regenerative or recuperative gas turbines is discussed. Finally, some of the problems which might be encountered in using this totally different power plant for the conventional automobile are identified.

Advanced Multi-Cup Fuel Injector Technology for Environmentally Responsible Aviation Gas Turbine Engines

2015 ◽  
Author(s):  
Erlendur Steinthorsson ◽  
Adel Mansour ◽  
Brian Hollon ◽  
Michael Teter ◽  
Clarence Chang
Keyword(s):  
Gas Turbine ◽  
Direct Injection ◽  
Pressure Ratio ◽  
Test Facility ◽  
Turbine Engines ◽  
Practical Implementation ◽  
Gas Turbine Engines ◽  
Fuel Injector ◽  
Ambient Conditions ◽  
Environmentally Responsible

Participating in NASA’s Environmentally Responsible Aviation (ERA) Project, Parker Hannifin built and tested multipoint Lean Direct Injection (LDI) fuel injectors designed for NASA’s N+2 55:1 Overall Pressure-Ratio (OPR) gas turbine engine cycles. The injectors are based on Parker’s earlier three-zone injector (3ZI) which was conceived to enable practical implementation of multipoint LDI schemes in conventional aviation gas turbine engines. The new injectors offer significant aerodynamic design flexibility, excellent thermal performance, and scalability to various engine sizes. The injectors built for this project contain 15 injection points and incorporate staging to enable operation at low power conditions. Ignition and flame stability were demonstrated at ambient conditions with ignition air pressure drop as low as 0.3% and fuel-to-air ratio (FAR) as low as 0.011. Lean Blowout (LBO) occurred at FAR as low as 0.005 with air at 460 K and atmospheric pressure. A high pressure combustion testing campaign was conducted in the CE-5 test facility at NASA Glenn Research Center at pressures up to 250 psi and combustor exit temperatures up to 2,033 K (3,200 °F). The tests demonstrated estimated LTO cycle emissions that are about 30% of CAEP/6 for a reference 60,000 lbf thrust, 54.8-OPR engine. This paper presents some details of the injector design along with results from ignition, LBO and emissions testing.

scholarly journals METHOD OF FORMULATING INPUT PARAMETERS OF NEURAL NETWORK FOR DIAGNOSING GAS-TURBINE ENGINES

Aviation ◽  
2013 ◽  
Vol 17 (2) ◽  
pp. 52-56 ◽  
Author(s):  
Mykola Kulyk ◽  
Sergiy Dmitriev ◽  
Oleksandr Yakushenko ◽  
Oleksandr Popov
Keyword(s):  
Neural Network ◽  
Gas Turbine ◽  
Gas Turbine Engine ◽  
Training Data ◽  
Turbine Engines ◽  
Data Sets ◽  
Gas Turbine Engines ◽  
Turbine Engine ◽  
Wide Range ◽  
And Training

A method of obtaining test and training data sets has been developed. These sets are intended for training a static neural network to recognise individual and double defects in the air-gas path units of a gas-turbine engine. These data are obtained by using operational process parameters of the air-gas path of a bypass turbofan engine. The method allows sets that can project some changes in the technical conditions of a gas-turbine engine to be received, taking into account errors that occur in the measurement of the gas-dynamic parameters of the air-gas path. The operation of the engine in a wide range of modes should also be taken into account.

A Mean Line Prediction Method for Axial Flow Turbine Efficiency

1982 ◽  
Vol 104 (1) ◽  
pp. 111-119 ◽  
Author(s):  
S. C. Kacker ◽  
U. Okapuu
Keyword(s):  
Gas Turbine ◽  
Axial Flow ◽  
Prediction Method ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Loss System ◽  
Turbine Efficiency ◽  
Wide Range ◽  
Line Loss ◽  
Axial Turbines

A mean line loss system is described, capable of predicting the design point efficiencies of current axial turbines of gas turbine engines. This loss system is a development of the Ainley/Mathieson technique of 1951. The prediction method is tested against the “Smith’s chart” and against the known efficiencies of 33 turbines of recent design. It is shown to be able to predict the efficiencies of a wide range of axial turbines of conventional stage loadings to within ± 1 1/2 percent.

scholarly journals On the effect of the meridional contour shape on the power characteristics of a centrifugal compressor wheel

2020 ◽  
Vol 2020 (3) ◽  
pp. 12-17
Author(s):  
Yu.A. Kvasha ◽  
◽  
N.A. Zinevych ◽  
Keyword(s):  
Gas Turbine ◽  
Centrifugal Compressor ◽  
Computational Study ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Compressor Wheel ◽  
Power Characteristics ◽  
Contour Shape ◽  
Wide Range ◽  
Uniformly Distributed Sequence

This work is concerned with the development of approaches to the optimal aerodynamic design of centrifugal compressor wheels, which is due to the use of centrifugal stages in compressors of modern aircraft gas turbine engines and power plants. The aim of this work is a computational study of the effect of the meridional contour shape of a centrifugal compressor wheel on its power characteristics. The basic method is a numerical simulation of 3D turbulent gas flows in centrifugal wheels on the basis of the complete averaged Navier¬–Stokes equations and a two-parameter turbulence model. The computational study features: varying the shape of the hub and tip part of the meridional contour over a wide range, formulating quality criteria as the mean integral values of the wheel power characteristics over the operating range of the air flow rate through the wheel, and a systematic scan of the independent variable range at points that form a uniformly distributed sequence. As a result of multiparameter calculations, it was shown that in the case of a flow without separation in the blade channels of a wheel with a given starting shape of the meridional contour, varying that shape has an insignificant effect on the wheel power characteristics. It is pointed out that in similar cases it seems to be advisable to aerodynamically improve centrifugal wheels by varying the shape of their blades in the circumferential direction rather than in the meridional plane. This conclusion was made using rather a “coarse” computational grid, which, however, retains the sensitivity of the computed results to a variation in the centrifugal wheel geometry. On the whole, this work clarifies ways of further aerodynamic improvement of centrifugal compressor impellers in cases where the starting centrifugal wheel is a well-designed wheel with a flow without separation in the blade channels. The results obtained may be used in the aerodynamic optimization of centrifugal stages of aircraft gas turbine engines.

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