Estimation of cooling flow rate for conceptual design stage of a gas turbine engine

Abstract The regional aircraft with a turbofan gas turbine engine, created in Russia, is successfully operated in the world market. Further increase of the life and reduction of the cost of the life cycle are necessary to ensure the competitive advantages of the engine. One of the units limiting the engine life is the compressor rotor. The cyclic life of the rotor depends on many factors: the stress-strain state in critical zones, the life of the material under low-cycle loading, the regime of engine operation, production deviations (within tolerances), etc. In order to verify the influence of geometry deviations, the calculations of the model with nominal dimensions and the model with the most unfavorable geometric dimensions (worst cases) have been carried out. The obtained influence coefficients for geometric and weight tolerances are then used for probabilistic modeling of stresses in the critical zone. Rotor speed and gas loads on the blades for different flight missions and engine wear are determined from the corresponding aerodynamic calculations taking into account the actual flight cycles (takeoff, reduction, reverse) and are also used for stress recalculations. The subsequent calculation of the rotor cyclic life and the resource assessment is carried out taking into account the spread of the material low-cycle fatigue by probabilistic modeling of the rotor geometry and weight loads. A preliminary assessment of the coefficients of tolerances influence on stress in the critical zone can be used to select the optimal (in terms of life) tolerances at the design stage. Taking into account the actual geometric and weight parameters can allow estimating the stress and expected life of each manufactured rotor.

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Compensation of Intake Induced Flow Non-Uniformities With Compressor Blade Lean Angle Changes

Volume 4: Cycle Innovations; Industrial and Cogeneration; Manufacturing Materials and Metallurgy; Marine ◽

10.1115/gt2009-59587 ◽

2009 ◽

Author(s):

Ioannis Templalexis ◽

Vassilios Pachidis ◽

Petros Kotsiopoulos

Keyword(s):

Gas Turbine ◽

Flow Simulation ◽

Gas Turbine Engine ◽

Compressor Blade ◽

Design Stage ◽

Computational Time ◽

Turbine Engine ◽

Lean Angle ◽

Compressor Performance ◽

Induced Flow

The compression system has traditionally drawn most of the attention concerning the gas turbine engine performance assessment and design procedure. It is the most vulnerable component to flow fluctuations within a gas turbine engine. In particular this study focuses on performance deviations, between an installed and an uninstalled compressor. Test results acquired from a test bed installation will differ from these recorded when the compressor operates as an integral part of the engine. The upstream duct, whether an intake or an interstage duct, will affect the flow field pattern ingested into the compressor. The case studies presented into this work aim to mostly qualify the effect of boundary layer growth along the upstream duct walls, upon compressor performance. Additionally, compressor performance response on blade lean angle variation is being addressed, with the aim of acquiring an understanding as to how compressor blade lean angle changes interact with intake induced flow non uniformities. Such studies are usually conducted during the preliminary design stage, before the compressor is built. Consequently, experimental performance investigation is excluded at this stage of development. Computer aided simulation techniques are between the few if not the only option for compressor performance prediction. Given the fact that many such design parameters need to be assessed under the time pressure exerted by the tight compressor development program, the compressor flow simulation technique used needs to provide reliable results while consuming the least possible computational time. Such a low computational time compressor flow simulation method, among others, is the two dimensional (2D) streamline curvature (SLC) method, being applied within the frame of reference of the current study. The paper is introduced by a brief discussion on SLC method that was proposed more than 50 years ago. Then a reference is made to the Radial Equilibrium Equation (REE) which is the mathematical basis of the code, commenting on the assumptions that were undertaken. Subsequently the influence of the intake presence on the compressor inlet radial flow distribution is being addressed, with the aim of adjusting compressor blade inlet lean angle, in order to minimize compressor performance deterioration. Finally the paper is concluded with a discussion of the results.

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Effect of Variable Guide Vanes and Natural Gas Hybridization for Accommodating Fluctuations in Solar Input to a Gas Turbine

Volume 4: Cycle Innovations; Fans and Blowers; Industrial and Cogeneration; Manufacturing Materials and Metallurgy; Marine; Oil and Gas Applications ◽

10.1115/gt2011-45331 ◽

2011 ◽

Author(s):

Kyle Kitzmiller ◽

Fletcher Miller

Keyword(s):

Gas Turbine ◽

Flow Rate ◽

Gas Turbine Engine ◽

Solar Thermal ◽

Guide Vanes ◽

Operational Strategies ◽

Turbine Engine ◽

Variable Nature ◽

Wide Range ◽

Solar Powered

In recent years, several prototype solar central receivers have been experimentally demonstrated to produce high temperature and high pressure gas capable of driving a gas turbine engine [1–4]. While these prototype receivers are generally small (< 1 MWth), advancements in this technology will allow for the development of solar powered gas turbine engines at a commercial level (sizes of at least several megawatts electric (MWe)). The current paper analyzes a recuperated solar powered gas turbine engine, and addresses engine considerations, such as material limitations, as well as the variable nature of solar input. In order to compensate for changes in solar input, two operational strategies are identified and analyzed. The first is hybridization, meaning the solar input is supplemented via the combustion of fossil fuels. Hybridization often allows for an increase in net power and efficiency by adding heat during periods of low solar thermal input. An alternative strategy is to make use of variable guide vanes on the compressor of the gas turbine engine, which schedule to change the air flow rate into the system. By altering the mass flow rate of air, and assuming a fixed level of heat addition, the operating temperature of the engine can be controlled to maximize power or efficiency. The paper examines how to combine hybridization with variable guide vane operation to optimize gas turbine performance over a wide range of solar thermal input, from zero to solar-only operation. A large material constraint is posed by the combustor, and to address this concern two alternative strategies — one employing a bypass valve and the other a combustor modified to allow higher temperature inlet air — are presented. Combustor modifications could include new materials and/or increased cooling air. The two strategies (bypass vs. no bypass) are compared on a thermodynamic basis. Finally, a yearly assessment of solar share and thermodynamic performance is presented for a 4.8 MWe gas turbine to identify the overall benefits of the operational strategies.

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Gas turbine engine disk risk assessment at the design stage taking into account random failures

Russian Aeronautics ◽

10.3103/s1068799813040065 ◽

2013 ◽

Vol 56 (4) ◽

pp. 359-364 ◽

Cited By ~ 2

Author(s):

A. I. Belousov ◽

A. V. Gritsin

Keyword(s):

Risk Assessment ◽

Gas Turbine ◽

Gas Turbine Engine ◽

Design Stage ◽

Turbine Engine ◽

Random Failures

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Experimental Investigation of an Inert Gas Generator for Fire Suppressing

Volume 3: Heat Transfer; Electric Power; Industrial and Cogeneration ◽

10.1115/2001-gt-0412 ◽

2001 ◽

Author(s):

SooYong Kim ◽

A. Slitenko

Keyword(s):

Experimental Investigation ◽

Gas Turbine ◽

Mass Flow Rate ◽

Oxygen Content ◽

Flow Rate ◽

Gas Turbine Engine ◽

Inert Gas ◽

Gas Generator ◽

Turbine Engine ◽

Exit Nozzle

Present study deals with experimental and theoretical performance analysis of an inert gas generator(IGG) which can be used as an effective mean to suppress the fire. The system consists of a gas turbine engine and afterburning system with injection of water, exit nozzle to produce the inert gas. It is generally known that the degree of oxygen content in the product of combustion depends on both inlet and outlet temperature of a combustor. Less the oxygen content in the combustion product higher will be the effectiveness of fire suppression. Injection of water brings additional advantages of suffocating and cooling effects which are both indespensable factors for fire suppressing. The special test rig was manufactured and experimental investigation of IGG system has been carried out. The automatic control system ensured stable operation of gas turbine engine and afterburner, water injection, fuel control and others. During the investigation the main parameters of gas turbine engine and auxiliarly systems were measured: gas temperature and pressure at gas turbine and afterburner exit, fuel flow rate, water mass flow rate, inlet air temperature, water temperature in the cooling chamber, mass flow rate, temperature and velocity of exhaust gas-steam mixture in the exit nozzle, oxygen content in the exit jet. The experimental investigation shows that developed IGG system can work very well for indoor fires but need some modifications in application to outdoor fire suppressing.

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Estimation of cooling flow rate for conceptual design stage of a gas turbine engine

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1177/09576509211014981 ◽

2021 ◽

pp. 095765092110149

Author(s):

EP Filinov ◽

VS Kuz’michev ◽

A Yu Tkachenko ◽

YaA Ostapyuk ◽

IN Krupenich

Keyword(s):

Gas Turbine ◽

Cooling System ◽

Numerical Models ◽

Turbine Blades ◽

Gas Turbine Engine ◽

Design Stage ◽

Inlet Temperature ◽

Turbine Engine ◽

Turbine Cooling ◽

Turbine Inlet

Development of a gas turbine engine starts with optimization of the working process parameters. Turbine inlet temperature is among the most influential parameters that largely determine performance of an engine. As typical turbine inlet temperatures substantially exceed the point where metal turbine blades maintain reasonable thermal strength, proper modeling of the turbine cooling system becomes crucial for optimization of the engine’s parameters. Currently available numerical models are based on empirical data and thus must be updated regularly. This paper reviews the published information on turbine cooling requirements, and provides an approximation curve that generalizes data on all types of blade/vane cooling and is suitable for computer-based optimization.

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THE METHOD OF CONTROLLING THE SUPPLY OF CRYOGENIC FUEL IN A GAS TURBINE ENGINE

Journal of Dynamics and Vibroacoustics ◽

10.18287/2409-4579-2020-6-3-33-40 ◽

2021 ◽

Vol 6 (3) ◽

pp. 33-40

Author(s):

V. A. Shishkov

Keyword(s):

Phase Transition ◽

Heat Exchanger ◽

Liquid Phase ◽

Power Plant ◽

Combustion Chamber ◽

Gas Turbine ◽

Flow Rate ◽

Internal Combustion Engines ◽

Gas Turbine Engine ◽

Turbine Engine

increasing the efficiency of the power plant. A method of controlling the supply of cryogenic fuel to a gas turbine engine is to pump its liquid phase, followed by its separation into two parts and controlling the flow rate of each part. Heated the first part of the cryogenic fuel to a gaseous state in the heat exchanger, mixing it with the second part and feeding the resulting mixture of cryogenic fuel into the combustion chamber. The first part of the cryogenic fuel flow rate is passed through the heat exchanger Gta = Gsm [Ср_sm (Тfp + T) il] / [ig il], where Gsm is the consumption of cryogenic fuel at the outlet of the mixer, Ср_sm is the isobaric heat capacity of cryogenic fuel at the outlet from the mixer, Тfp is the temperature of the phase transition of cryogenic fuel from liquid to gas at a pressure in the mixer, T is the temperature of the gas mixture of cryogenic fuel at the outlet of the mixer above the temperature of the phase transition, il is the enthalpy of the first part of the liquid phase of cryogenic fuel at the input ode to the heat exchanger and the second part of the liquid phase of the cryogenic fuel, which is fed to the second entrance to the mixer, ig is the enthalpy of the gaseous phase of the cryogenic fuel at the outlet of the heat exchanger, at which it is fed to the first entrance to the mixer. Moreover, ig Ср_sm (Тfp + T) il and Gsm = Gta + Gl, where Gl is the flow rate of the second part of the liquid phase of the cryogenic fuel, which is fed to the second input to the mixer. When the pressure of the cryogenic fuel in the mixer is below the critical value Pkr, the temperature Тfp of the phase transition from liquid to gas of the cryogenic fuel is taken equal to the temperature Тnas on the saturation line of the cryogenic fuel at the corresponding pressure in the mixer. The excess of the temperature of the cryogenic fuel mixture over the phase transition temperature after mixing the gas and liquid phases at the mixer outlet sets T = 60 ... 170 for cryogenic methane and T = 150 ... 260 for cryogenic hydrogen. Due to the gasification of a part of the cryogenic fuel consumption in the heat exchanger and subsequent mixing of this part with the second liquid part of the cryogenic fuel in the mixer, the freezing of the outer surface of the heat exchanger in all operating modes of the power plant is reduced. Due to the reduction of external freezing of the channels of the heat exchanger, the heat transfer efficiency is increased in it. By reducing the dimensions of the heat exchanger, the hydraulic losses in the gas-dynamic path of the power plant are reduced, which, in turn, increases its efficiency. By lowering the temperature of the gas phase of the cryogenic fuel at the inlet to the combustion chamber, the temperature of the exhaust gases at its outlet is reduced, which, in turn, increased the reliability of the gas turbine of the power plant. The method of operation of the cryogenic fuel supply system is intended for ground-based power plants and vehicles. The work is intended for scientists and designers in the field of cryogenic fuels for internal combustion engines.

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