scholarly journals Gas turbine power calculation method of turboshaft based on simulation and performance model

2018 ◽  
Vol 189 ◽  
pp. 02003 ◽  
Author(s):  
Heng Wu ◽  
Shufan Zhao ◽  
Jijun Zhang ◽  
Bo Sun ◽  
Hanqiang Song
Keyword(s):  
Steady State ◽  
Combustion Chamber ◽  
Gas Turbine ◽  
Calculation Method ◽  
Performance Model ◽  
Power Calculation ◽  
Outlet Temperature ◽  
Acceptance Test ◽  
Test Drive ◽  
Turboshaft Engine

Gas turbine power of turboshaft engine cannot be measured, a total of five typical steady state point test data from the ground slow state to the maximum state were selected according to the factory acceptance test drive of a certain type of carrier-based helicopter turboshaft engine. Combustion chamber three-dimensional simulation model was established to carry on simulation analysis of different typical steady state combustion process. The simulated combustion chamber exit section parameters are input into the established gas turbine isentropic adiabatic aerodynamic calculation model to obtain the gas turbine power and outlet temperature. Select five typical steady state points of five sets of turboshaft engines on the same type to repeat the above calculation process, and compare the calculated value of gas turbine outlet temperature with the acceptance test values, it is found that the error values are all within 5%, and the effectiveness and accuracy of the gas turbine power calculation method are verified.

scholarly journals Design and Experimental Validation of a Supersonic Concentric Micro Gas Turbine

2015 ◽  
Vol 138 (2) ◽  
Author(s):  
Gabriel Vézina ◽  
Hugo Fortier-Topping ◽  
François Bolduc-Teasdale ◽  
David Rancourt ◽  
Mathieu Picard ◽  
...  
Keyword(s):  
Steady State ◽  
Combustion Chamber ◽  
Gas Turbine ◽  
Structural Model ◽  
Structural Integrity ◽  
Turbine Blades ◽  
External Diameter ◽  
Impulse Turbine ◽  
Micro Gas Turbine ◽  
Steady State Operation

This paper presents the design and experimental results of a new micro gas turbine architecture exploiting counterflow within a single supersonic rotor. This new architecture, called the supersonic rim-rotor gas turbine (SRGT), uses a single rotating assembly incorporating a central hub, a supersonic turbine rotor, a supersonic compressor rotor, and a rim-rotor. This SRGT architecture can potentially increase engine power density while significantly reducing manufacturing costs. The paper presents the preliminary design of a 5 kW SRGT prototype having an external diameter of 72.5 mm and rotational speed of 125,000 rpm. The proposed aerodynamic design comprises a single stage supersonic axial compressor, with a normal shock in the stator, and a supersonic impulse turbine. A pressure ratio of 2.75 with a mass flow rate of 130 g/s is predicted using a 1D aerodynamic model in steady state. The proposed combustion chamber uses an annular reverse-flow configuration, using hydrogen as fuel. The analytical design of the combustion chamber is based on a 0D model with three zones (primary, secondary, and dilution), and computational fluid dynamics (CFD) simulations are used to validate the analytical model. The proposed structural design incorporates a unidirectional carbon-fiber-reinforced polymer rim-rotor, and titanium alloy is used for the other rotating components. An analytical structural model and numerical validation predict structural integrity of the engine at steady-state operation up to 1000 K for the turbine blades. Experimentation has resulted in the overall engine performance evaluation. Experimentation also demonstrated a stable hydrogen flame in the combustion chamber and structural integrity of the engine for at least 30 s of steady-state operation at 1000 K.

Validation of a Gas Turbine Thermodynamic Model Without Accurate Component Maps

2017 ◽  
Author(s):  
Anthony Jarrett ◽  
Ying Chen
Keyword(s):  
Gas Turbine ◽  
Thermodynamic Model ◽  
Performance Model ◽  
Test Cell ◽  
Inlet Temperature ◽  
Power Calculation ◽  
Analysis Tool ◽  
Discharge Temperature ◽  
Operating Points ◽  
Cell Data

The authors have developed an engine performance model for use within a physics-based analysis tool to predict gas turbine engine life. The model employs a multivariate optimization method to solve the gas turbine thermodynamic equations, and incorporates a calibration phase to capture the behavior of individual engines without requiring accurate component maps. To validate this approach, a database of test cell data for a turboprop engine has been used. The data consists of approximately 80 engine tests; each one with five operating points. Using a cross-validation method, each engine was uniquely calibrated using four of the operating points, and then validated using parameters from the fifth operating point. To benchmark the calibration process, these analyses were repeated without the calibration stage. The un-calibrated outputs showed a lack of both precision and accuracy, due to imprecision in the component maps, and variation from engine to engine. In contrast, the calibrated outputs of compressor discharge temperature (CDT), compressor discharge pressure (CDP), and turbine inlet temperature (TIT) were predicted within 1% error for more than 95% of all cases. Although most of the key thermodynamic parameters were predicted accurately, we have found that the shaft power calculation demonstrates some significant deviations from the test cell data. This has been attributed to the formulation of the turboprop thermodynamic model, and ongoing work is attempting to mitigate this issue. This understanding of the characteristic engine algorithms will provide valuable guidance in selecting suitable engine parameters as inputs and references.

Transient Performance Analysis of an Industrial Gas Turbine Operating on Low-Calorific Fuels

2016 ◽  
Vol 139 (5) ◽  
Author(s):  
Vrishika Singh ◽  
Lars-Uno Axelsson ◽  
W.P.J. Visser
Keyword(s):  
Steady State ◽  
Energy Density ◽  
Gas Turbine ◽  
Alternative Fuels ◽  
Combustion Process ◽  
Transient Behavior ◽  
Performance Model ◽  
Transient Performance ◽  
Wide Range ◽  
Industrial Gas Turbine

The demand for more environmentally friendly and economic power production has led to an increasing interest to utilize alternative fuels. In the past, several investigations focusing on the effect of low-calorific fuels on the combustion process and steady-state performance have been published. However, it is also important to consider the transient behavior of the gas turbine when operating on nonconventional fuels. The alternative fuels contain very often a large amount of dilutants resulting in a low energy density. Therefore, a higher fuel flow rate is required, which can impact the dynamic behavior of the gas turbine. This paper will present an investigation of the transient behavior of the all-radial OP16 gas turbine. The OP16 is an industrial gas turbine rated at 1.9 MW, which has the capability to burn a wide range of fuels including ultra-low-calorific gaseous fuels. The transient behavior is simulated using the commercial software GSP including the recently added thermal network modeling functionality. The steady-state and transient performance model is thoroughly validated using real engine test data. The developed model is used to simulate and analyze the physical behavior of the gas turbine when performing load sheds. From the simulations, it is found that the energy density of the fuel has a noticeable effect on the rotor over-speed and must be considered when designing the fuel control.

scholarly journals High-Resolution One-Dimensional Modeling of a Gas Turbine Combustor Using Eulerian-Lagrangian Method

2019 ◽  
Author(s):  
Reza Khodadadi ◽  
Nima Zamani Meymian
Keyword(s):  
Combustion Chamber ◽  
Gas Turbine ◽  
Flow Rate ◽  
Energy Equation ◽  
Source Term ◽  
Outlet Temperature ◽  
Lagrangian Coordinates ◽  
Gas Turbine Combustor ◽  
Time Step ◽  
One Dimensional

In this paper, a dynamic combustor model for inclusion into a one-dimensional full gas turbine engine simulation model, with high numerical accuracy is developed. Effects of dominant parameters, such as frequency and amplitude of the inlet air and fuel mass flow rate fluctuations, on outlet temperature of the combustion chamber, are investigated. The main goal of this research is to analyze the response of the gas turbine combustor to dynamic events that occur in the compressor. In the present work, for modeling combustion, the equations of chemical equilibrium (a second-law concept) are developed and applied to combustion-product mixtures. Thus the heat released from combustion is computed and used as a source term in the energy equation. Ignition effects either would be considered with a time lag equation as a source term in the energy equation. The combustor flammability limits are determined by using available experimental data for various gases and also Le Chatelier’s law. Source terms of governing equations are added using the operator splitting method. To operate this, the modified version of the PPM algorithm called PPMLR is used which solves the Euler equations in Lagrangian coordinates. At the end of each time step, results calculated in the Lagrangian coordinates would remap to the original Eulerian coordinate. The results revealed that to achieve a grid-independent solution, the accuracy of 0.002 m over the length of the combustion chamber should be applied. By reducing the accuracy of simulation, numerical diffusion causes a rise in flow temperature along with the combustion chamber. Through the dynamic modeling aspect, it is found that by increasing inlet fuel flow rate frequency up to 25 Hz, the amplitude of the fluctuations of outlet temperature, increases. Further increase in frequency up to 100 Hz, the amplitude of the fluctuations remains unchanged. However further increases in frequency from 100 Hz, causes amplitudes of outlet temperature fluctuations to decrease.

3-Dimensional Pressure Driven Temperature Field in a Gas Turbine Combustion Chamber

2006 ◽  
Author(s):  
Fernando Z. Sierra ◽  
Areli Uribe ◽  
Janusz Kubiak ◽  
Hugo Lara ◽  
Gustavo Urquiza ◽  
...  
Keyword(s):  
Temperature Field ◽  
Steady State ◽  
Temperature Distribution ◽  
Combustion Chamber ◽  
Gas Turbine ◽  
Air Flow ◽  
Combined Cycle ◽  
3 Dimensional ◽  
Gas Fuel ◽  
Gas Turbine Combustion

In this work the temperature field in a gas turbine combustion chamber is investigated through numerical computations. The combustion chamber under study is part of a 70 MW gas turbine from an operating combined cycle power plant. The simulation of combustion and flow dynamics is fully 3-dimensional. It addresses complex turbulence structure and temperature distribution inside the combustion chamber. The swirling effect is taken into account using a detailed gas-fuel-air mixing swirler. The combustion was simulated with proper gas-fuel-air flow ratio assuming stoichiometric equilibrium conditions. Based on previous results, pressure imbalance conditions of air flow between primary and secondary inlets is used to perturb the temperature distribution. In this work, a periodic function was used to produce pressure variation in the air flow, which in turn alter the temperature field and turbulence structures. First, characteristic temperature and pressure fields were obtained using steady state boundary conditions. The steady state solutions were perturbed using a periodic boundary condition (6 kPa per short periods of time) resulting in different results. The results are discussed and confirm previous 2-dimesional computations where excessive heating in regions other than the combustion chamber core occurred. The investigation is aimed to explain why overheating occurs, since it causes burning out of pipe materials, producing permanent damage to auxiliary cross flame pipes.

Steady-State and Transient Performance Modeling of Smart UAV Propulsion System Using SIMULINK

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Jayoung Ki ◽  
Changduk Kong ◽  
Seonghee Kho ◽  
Changho Lee
Keyword(s):  
Steady State ◽  
Simulation Model ◽  
Gas Turbine ◽  
Mass Flow ◽  
Performance Model ◽  
Performance Estimation ◽  
Transient Performance ◽  
Performance Simulation ◽  
Comparison Results ◽  
Steady State Performance

Because an aircraft gas turbine operates under various flight conditions that change with altitude, flight velocity, and ambient temperature, the performance estimation that considers the flight conditions must be known before developing or operating the gas turbine. More so, for the unmanned aerial vehicle (UAV) where the engine is activated by an onboard engine controller in emergencies, the precise performance model including the estimated steady-state and transient performance data should be provided to the engine control system and the engine health monitoring system. In this study, a graphic user interface (GUI) type steady-state and transient performance simulation model of the PW206C turboshaft engine that was adopted for use in the Smart UAV was developed using SIMULINK for the performance analysis. For the simulation model, first the component maps including the compressor, gas generator turbine, and power turbine were inversely generated from the manufacturer’s limited performance deck data by the hybrid method. For the work and mass flow matching between components of the steady-state simulation, the state-flow library of SIMULINK was applied. The proposed steady-state performance model can simulate off-design point performance at various flight conditions and part loads, and in order to evaluate the steady-state performance model their simulation results were compared with the manufacturer’s performance deck data. According to comparison results, it was confirmed that the steady-state model agreed well with the deck data within 3% in all flight envelopes. In the transient performance simulation model, the continuity of mass flow (CMF) method was used, and the rotational speed change was calculated by integrating the excess torque due to the transient fuel flow change using the Runge–Kutta method. In this transient performance simulation, the turbine overshoot was predicted.

Steady-State and Transient Performance Modeling of Smart UAV Propulsion System Using SIMULINK

2008 ◽  
Author(s):  
Jayoung Ki ◽  
Changduk Kong ◽  
Seonghee Kho ◽  
Changho Lee
Keyword(s):  
Steady State ◽  
Simulation Model ◽  
Gas Turbine ◽  
Mass Flow ◽  
Performance Model ◽  
Performance Estimation ◽  
Transient Performance ◽  
Performance Simulation ◽  
Comparison Results ◽  
Steady State Performance

Because aircraft gas turbine operates under various flight conditions that changes with altitude, flight velocity and ambient temperature, performance estimation that considers the flight conditions must be known before developing or operating the gas turbine. More so, for the UAV (Unmanned Aerial Vehicle) where the engine is activated by an onboard engine controller in emergency, the precise performance model including the estimated steady-state and transient performance data should be provided to the engine control system and the engine health monitoring system. In this study, a GUI (Graphic User Interface) type steady-state and transient performance simulation model of the PW206C turbo shaft engine that was adopted for use on the Smart UAV was developed using SIMULINK for performance analysis. For the simulation model, firstly the component maps including compressor, gas generator turbine and power turbine were inversely generated from manufacturer’s limited performance deck data by Hybrid Method. For the work and mass flow matching between components of the steady-state simulation, the state-flow library of SIMULINK was applied. The proposed steady-state performance model can simulate off-design point performance at various flight conditions and part loads, and in order to evaluate the steady-state performance model their simulation results were compared with manufacturer’s performance deck data. According to comparison results, it was confirm that the steady-state model well agreed with the deck data within 3% in all flight envelop. In the transient performance simulation model, the CMF (Continuity of Mass Flow) method was used and the rotational speed change was calculated by integrating the excess torque due to the transient fuel flow change using Runge-Kutta method. In this transient performance simulation, the turbine overshoot was predicted.

Transient Performance Analysis of an Industrial Gas Turbine Operating on Low-Calorific Fuels

2016 ◽  
Author(s):  
Vrishika Singh ◽  
Lars-Uno Axelsson ◽  
W. P. J. Visser
Keyword(s):  
Steady State ◽  
Energy Density ◽  
Gas Turbine ◽  
Alternative Fuels ◽  
Combustion Process ◽  
Transient Behavior ◽  
Performance Model ◽  
Transient Performance ◽  
Wide Range ◽  
Industrial Gas Turbine

The demand for more environmentally friendly and economic power production has led to an increasing interest to utilize alternative fuels. In the past, several investigations focusing on the effect of low-calorific fuels on the combustion process and steady-state performance have been published. However, it is also important to consider the transient behavior of the gas turbine when operating on non-conventional fuels. The alternative fuels contain very often a large amount of dilutants resulting in a low energy density. Therefore a higher fuel flow rate is required, which can impact the dynamic behavior of the gas turbine. This paper will present an investigation of the transient behavior of the all-radial OP16 gas turbine. The OP16 is an industrial gas turbine rated at 1.9 MW, which has the capability to burn a wide range of fuels including ultra-low-calorific gaseous fuels. The transient behavior is simulated using the commercial software GSP including the recently added thermal network modeling functionality. The steady-state and transient performance model is thoroughly validated using real engine test data. The developed model is used to simulate and analyze the physical behavior of the gas turbine when performing load sheds. From the simulations it is found that the energy density of the fuel has a noticeable effect of the rotor over-speed and must be considered when designing the fuel control.

Analysis of Pressure Oscillations Data in Gas Turbine Annular Combustion Chamber Equipped With Passive Damper

2005 ◽  
Author(s):  
M. Mastrovito ◽  
S. M. Camporeale ◽  
A. Forte ◽  
B. Fortunato
Keyword(s):  
Combustion Chamber ◽  
Gas Turbine ◽  
Pressure Field ◽  
Stability Limit ◽  
Outlet Temperature ◽  
Test Bed ◽  
Combustion Chambers ◽  
Pressure Oscillations ◽  
Theoretical Approaches ◽  
The Stability

Growing environmental awareness, the current legislations, and the increasing competition in the energy market lead gas turbine manufacturers to develop combustion chambers that have to guarantee low NOx emissions, low pressure drop and high combustor outlet temperature. Modern annular and can-type gas turbine combustion chambers, able to work in lean premixed mode, show a remarkable attitude to produce flame instabilities, well known as humming. Many theoretical approaches have been proposed in order to describe the phenomenon and predict the stability margin of the burner. Experimental tests are needed to assess mathematical models and to evaluate the effects of either active or passive methodologies adopted to reduce combustion driven instabilities. Tests have been carried out at the Ansaldo Caldaie test bed on a real-size annular combustion chamber, equipped with a certain number of Helmholtz resonators. The combustion chamber has been instrumented with piezoelectric and opto-electronic transducers in order to determine the pressure field both in proximity of the instability limit and in humming condition. When pressure data are collected before than humming appears, pressure oscillations are much lower than those gathered in humming conditions; therefore, by using sensors designed to work under the pressure levels characterising the humming conditions, difficulties arise in proximity of the stability limit due the low signal-to-noise ratio. In this paper some techniques used to analyse the data gathered from the tests will be shown. Moreover, a simple algorithm capable to analyse a large amount of data and to synthesise them into a few significant parameters useful for the spectral analysis of the pressure field, has been validated by means of both real and simulated signals.

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