Numerical and Experimental Study on the Suppression for the Infrared Signatures of a Marine Gas Turbine Exhaust System

The flow and thermal fields within the cooling air injection device which is widely used to suppress the infrared (IR) signatures of a marine gas turbine exhaust system were studied numerically and experimentally. A turbulence near-wall model based on the wall function method was adopted. The discretization equations were derived for the control volumes when conjugate heat transfer exists at their interfaces, with the radiation heat flux at the interfaces appearing as an additional source term. The solution method of entrained velocities at the entrance of secondary flow was introduced. The distributions of temperature and static pressure on the diffuser surface, and the temperature of gas at the outlet of the exhaust duct were simulated numerically. The numerical calculated results agreed well with corresponding scale model experimental data. Lastly, the measured IR radiation distributions by scale model experiments at different view angles and various engine power settings, with and without IR signature suppression (IRSS) devices were presented.

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The Effects of Scale Factor on the Aero-Thermodynamic and Infrared Radiation Performance of Naval Gas Turbine Exhaust System With Infrared Signature Suppression Device

Volume 3A: General ◽

10.1115/93-gt-232 ◽

1993 ◽

Cited By ~ 1

Author(s):

Fangyuan Zhong ◽

Yu Dai

Keyword(s):

Gas Turbine ◽

Tube Wall ◽

Exhaust System ◽

Scale Factor ◽

Scale Model ◽

Exhaust Plumes ◽

Infrared Signature ◽

Different Dimensions ◽

Gas Turbine Exhaust ◽

Turbine Exhaust

On the basis of scale model tests in two different dimensions of marine gas turbine exhaust system with infrared signature suppression device, and in the light of similarity analysis and simplified numerical calculation, this paper discusses the effects of scale factor on the flow (flow resistance), temperature (of air-flow and tube wall), and infrared radiant (of exhaust plumes and exhaust uptake inner wall) fields of the exhaust system, and accordingly estimates the corresponding parameters of real ship exhaust systems as well as presents the magnitude of scale factor impacts and the recommended values for selecting the scale factor.

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Flow Guiding and Distributing Devices on the Exhaust Side of Stationary Gas Turbines

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2906481 ◽

1990 ◽

Vol 112 (1) ◽

pp. 80-85

Author(s):

F. Fleischer ◽

C. Koerner ◽

J. Mann

Keyword(s):

Gas Turbine ◽

Gas Turbines ◽

Gas Flow ◽

Flow Simulation ◽

Exhaust System ◽

Flow Distribution ◽

Scale Model ◽

Gas Turbine Exhaust ◽

First Time ◽

Turbine Exhaust

Following repeated cases of damage caused to exhaust silencers located directly beyond gas turbine diffusers, this paper reports on investigations carried out to determine possible remedies. In all instances, an uneven exhaust gas flow distribution was found. The company’s innovative approach to the problem involved constructing a scale model of a complete gas turbine exhaust system and using it for flow simulation purposes. It was established for the first time that, subject to certain conditions, the results of tests conducted on a model can be applied to the actual turbine exhaust system. It is shown that when an unfavorable duct arrangement might produce an uneven exhaust flow, scale models are useful in the development of suitable flow-distributing devices.

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Establishing the Longitudinal Temperature Distribution for Fully Developed Turbulent Flow in a Gas Turbine Exhaust Duct

Volume 1A: General ◽

10.1115/70-gt-16 ◽

1970 ◽

Author(s):

P. J. Torpey ◽

R. M. Welch

Keyword(s):

Temperature Distribution ◽

Gas Turbine ◽

Accurate Determination ◽

Exhaust System ◽

Longitudinal Temperature ◽

Exhaust Duct ◽

Fully Developed Turbulent Flow ◽

Gas Turbine Exhaust ◽

Heat Flow Model ◽

Turbine Exhaust

The ability to predict the longitudinal temperature distribution along a gas turbine exhaust duct facilitates the selection of the proper duct material and the appropriate paint or other external coating. It also allows accurate determination of thermal expansion over the entire length. A first-order differential equation is derived from a one-dimensional heat flow model for the exhaust system. A digital computer program employing this model is also presented. The computer solution, in addition to eliminating tedious manual computation, extends the analysis capability by accounting for changes in temperature and flow-dependent variables along the duct length. Measured gas and duct wall temperatures for a 1.5-kw gas turbine exhaust system are compared with values predicted by the analysis. Good agreement is noted throughout that portion of the system in which fully developed flow exists.

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Experimental and 3D CFD Investigation in a Gas Turbine Exhaust System

Volume 1: Turbomachinery ◽

10.1115/98-gt-111 ◽

1998 ◽

Cited By ~ 2

Author(s):

Bijay K. Sultanian ◽

Shinichiro Nagao ◽

Taro Sakamoto

Keyword(s):

Flow Field ◽

Gas Turbine ◽

Exhaust System ◽

Internal Flow ◽

Scale Model ◽

Laser Doppler Velocimeter ◽

Complex Flow ◽

Full Speed ◽

Gas Turbine Exhaust ◽

Turbine Exhaust

Both experimental and 3D CFD investigations are carried out in a scale model of an industrial gas turbine exhaust system to better understand its complex flow field and to validate CFD prediction capabilities for improved design applications. The model consists of an annular diffuser passage with struts, followed by turning vanes and a rectangular plenum with side exhaust. Precise measurements of total/static pressure and flow velocity distributions at the model inlet, strut outlet and model outlet are made using aerodynamic probes and locally a Laser Doppler Velocimeter (LDV). Numerical analyses of the model internal flow field are performed utilizing a three-dimensional Navier-Stokes (N-S) calculation method with the industry standard k-ε turbulence model. Both the experiments and computations are carried out for three load conditions: full speed no load (FSNL), full speed mid load (FSML, 57% load), and full speed full load (FSFL). Based on the overall comparison between the measurements and CFD predictions, this study concludes that the applied N-S method is capable of predicting complicated gas turbine exhaust system flows for design applications.

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Experimental and Three-Dimensional CFD Investigation in a Gas Turbine Exhaust System

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2817129 ◽

1999 ◽

Vol 121 (2) ◽

pp. 364-374 ◽

Cited By ~ 8

Author(s):

B. K. Sultanian ◽

S. Nagao ◽

T. Sakamoto

Keyword(s):

Flow Field ◽

Gas Turbine ◽

Three Dimensional ◽

Exhaust System ◽

Scale Model ◽

Laser Doppler Velocimeter ◽

Complex Flow ◽

Full Speed ◽

Gas Turbine Exhaust ◽

Turbine Exhaust

Both experimental and three-dimensional CFD investigations are carried out in a scale model of an industrial gas turbine exhaust system to better understand its complex flow field and to validate CFD prediction capabilities for improved design applications. The model consists of an annular diffuser passage with struts, followed by turning vanes and a rectangular plenum with side exhaust. Precise measurements of total/static pressure and flow velocity distributions at the model inlet, strut outlet and model outlet are made using aerodynamic probes and locally a Laser Doppler Velocimeter (LDV). Numerical analyses of the model internal flow field are performed utilizing a three-dimensional Navier-Stokes (N-S) calculation method with the industry standard k-ε turbulence model. Both the experiments and computations are carried out for three load conditions: full speed no load (FSNL), full speed mid load (FSML, 57 percent load), and full speed full load (FSFL). Based on the overall comparison between the measurements and CFD predictions, this study concludes that the applied N-S method is capable of predicting complicated gas turbine exhaust system flows for design applications.

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Flow Guiding and Distributing Devices on the Exhaust Side of Stationary Gas Turbines

Volume 4: Heat Transfer; Electric Power; Industrial and Cogeneration ◽

10.1115/89-gt-214 ◽

1989 ◽

Cited By ~ 1

Author(s):

Friedrich Fleischer ◽

Christian Koerner ◽

Juergen Mann

Keyword(s):

Gas Turbine ◽

Gas Turbines ◽

Gas Flow ◽

Flow Simulation ◽

Exhaust System ◽

Flow Distribution ◽

Scale Model ◽

Gas Turbine Exhaust ◽

First Time ◽

Turbine Exhaust

Following repeated cases of damage caused to exhaust silencers located directly beyond gas turbine diffusers, this paper reports on investigations carried out to determine possible remedies. In all instances, an uneven exhaust gas flow distribution was found to be present. The company’s innovative approach to the problem involved constructing a scale model of a complete gas turbine exhaust system and using it for flow simulation purposes. It was established for the first time that, subject to certain conditions, the results of tests conducted on a model can be applied to the actual turbine exhaust system. It is shown that when an unfavourable duct arrangement might produce an uneven exhaust flow, scale models are useful in the development of suitable flow-distributing devices.

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Acoustic Characteristics of a Gas Turbine Exhaust Model

Journal of Engineering for Power ◽

10.1115/1.3445791 ◽

1974 ◽

Vol 96 (3) ◽

pp. 181-184 ◽

Cited By ~ 1

Author(s):

J. R. Cummins

Keyword(s):

Gas Turbine ◽

Acoustic Radiation ◽

Flow Path ◽

Scale Model ◽

Temperature Ratio ◽

Acoustic Characteristics ◽

Gas Turbine Exhaust ◽

Acoustical Data ◽

Turbine Exhaust

To investigate the sources of acoustic radiation from a gas turbine exhaust, a one-seventh scale model has been constructed. The model geometrically scales the flow path downstream of the rotating parts including support struts and turning vanes. A discussion and comparison of different kinds of aerodynamic and acoustic scaling techniques are given. The effect of the temperature ratio between model and prototype is found to be an important parameter in comparing acoustical data.

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Prediction of Pressure Rise in a Gas Turbine Exhaust Duct Under Flameout Scenarios While Operating On Hydrogen and Natural Gas Blends

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4052358 ◽

2021 ◽

Author(s):

Orlando Ugarte ◽

Suresh Menon ◽

Wayne Rattigan ◽

Paul Winstanley ◽

Priyank Saxena ◽

...

Keyword(s):

Natural Gas ◽

Gas Turbine ◽

Combustion Process ◽

Pressure Rise ◽

Combustion Model ◽

Computational Domain ◽

Cfd Model ◽

Exhaust Duct ◽

Gas Turbine Exhaust ◽

Turbine Exhaust

Abstract In recent years, there is a growing interest in blending hydrogen with natural gas fuels to produce low carbon electricity. It is important to evaluate the safety of gas turbine packages under these conditions, such as late-light off and flameout scenarios. However, the assessment of the safety risks by performing experiments in full-scale exhaust ducts is a very expensive and, potentially, risky endeavor. Computational simulations using a high fidelity CFD model provide a cost-effective way of assessing the safety risk. In this study, a computational model is implemented to perform three dimensional, compressible and unsteady simulations of reacting flows in a gas turbine exhaust duct. Computational results were validated against data obtained at the simulated conditions in a representative geometry. Due to the enormous size of the geometry, special attention was given to the discretization of the computational domain and the combustion model. Results show that CFD model predicts main features of the pressure rise driven by the combustion process. The peak pressures obtained computationally and experimentally differed in 20%. This difference increased up to 45% by reducing the preheated inflow conditions. The effects of rig geometry and flow conditions on the accuracy of the CFD model are discussed.

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A Fluidic Technique for Measuring the Average Temperature in a Gas Turbine Exhaust Duct

Journal of Engineering for Power ◽

10.1115/1.3609185 ◽

1968 ◽

Vol 90 (3) ◽

pp. 265-270 ◽

Cited By ~ 1

Author(s):

C. G. Ringwall ◽

L. R. Kelley

Keyword(s):

Gas Turbine ◽

Wave Velocity ◽

Test Data ◽

Output Pressure ◽

Average Temperature ◽

Phase Discrimination ◽

Exhaust Duct ◽

Average Wave ◽

Gas Turbine Exhaust ◽

Turbine Exhaust

Circuit concepts and test data for a fluidic system to sense the average temperature in a gas turbine exhaust duct are presented. Phase discrimination techniques are used to sense the average wave velocity in a long tube and to produce an output pressure differential proportional to temperature error.

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