Experimental investigation of applicability limits of K-e turbulent model and Reynolds stresses transfer model in rotary-divergent flow under control via turning blades

This paper presents the experimental and numerical investigation on flowfield of multiple film cooling hole focuses on shallow hole angle at 20°. An in-line hole configuration consist of 20 cooling holes have been considered in the present study. Investigation have been carried out at ReD=6,200 and BR=1.0 with the experimental investigation involves 3D-LDV device to capture the experimental velocity flowfield. The numerical investigation was carried out through RANS analyses with the employment of shear stress transport turbulent model. The results highlights the benefit of shallow hole angle configuration with good agreements have been achieved between the experimental and the numerical results.

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Momentum Transfer Model for Reynolds Stresses

Journal of the Hydraulics Division ◽

10.1061/jyceaj.0004858 ◽

1977 ◽

Vol 103 (10) ◽

pp. 1232-1237

Author(s):

Robert Gerard

Keyword(s):

Momentum Transfer ◽

Transfer Model ◽

Reynolds Stresses

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VELOCITY FIELD IN A STEADY BREAKER

Coastal Engineering Proceedings ◽

10.9753/icce.v17.30 ◽

1980 ◽

Vol 1 (17) ◽

pp. 30

Author(s):

J.A. Battjes ◽

T. Sakai

Keyword(s):

Experimental Investigation ◽

Velocity Field ◽

Flow Field ◽

Turbulent Flow ◽

Turbulent Wake ◽

Laser Doppler ◽

Reynolds Stresses ◽

Doppler System ◽

Steady Current ◽

Turbulent Flow Field

An experimental investigation is described of the velocity field in a steady, spilling-type breaker, generated on a steady current by a submerged hydrofoil. Velocities have been measured with a laser-doppler system, and analysed with respect to mean and rms-values as well as Reynolds stresses. The results indicate that the turbulent flow field downstream of the initiation of the separation at the surface resembles that in a turbulent wake.

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Development of Film Cooled Thruster for Rocket Application

Volume 1: Compressors, Fans, and Pumps; Turbines; Heat Transfer; Structures and Dynamics ◽

10.1115/gtindia2019-2320 ◽

2019 ◽

Author(s):

Avanish Kumar ◽

V. Venkateswarlu ◽

P. Satyaprasad ◽

M. Raghavendra Rao

Keyword(s):

Heat Transfer ◽

Experimental Investigation ◽

Film Cooling ◽

Infrared Camera ◽

Outer Wall ◽

Pulse Mode ◽

Heat Transfer Model ◽

Transfer Model ◽

Core Flow ◽

Bottom Side

Abstract An experimental investigation has been carried out for small liquid bi-propellant thrusters of 490 & 1500 N levels. These thrusters have to operate for more than 100 sec in continuous and pulse mode. In this case, film cooling is the primary mode of thruster cooling. The thruster uses hydrazine based propellant as fuel and N2O4 as oxidiser. Film cooling is carried out by injecting a fraction of fuel from an injector periphery. Unlike impinging type injection elements are used for core flow. The thruster’s shell used for testing was made of stainless steel and di-silicide coated C103 material. A 1D heat transfer model was developed for predicting the thruster outer wall temperature. The experimental investigation was carried for different film cooling percentage and injector configuration was modified for each case. Thermocouples were mounted on top & bottom side of shell for temperature measurement. Infrared camera also used for recording temperature in the test. Based on experimental investigation, effective film cooling percentage for optimum thruster performance has been estimated for two thrust levels and these studies also helped in validating the heat transfer model.

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Characteristics of the wake behind a cascade of airfoils

Journal of Fluid Mechanics ◽

10.1017/s002211207300090x ◽

1973 ◽

Vol 61 (4) ◽

pp. 707-730 ◽

Cited By ~ 62

Author(s):

R. Raj ◽

B. Lakshminarayana

Keyword(s):

Experimental Investigation ◽

Decay Rate ◽

Flat Plate ◽

Reynolds Stress ◽

Turbulence Intensity ◽

Reynolds Stresses ◽

Mean Velocity ◽

Velocity Defect ◽

Velocity Turbulence ◽

Far Wake

An analytical and experimental investigation of the near and far wake characteristics of a cascade of airfoils is reported in this paper. The measurement of mean velocity, turbulence intensity and Reynolds stress across the wake at several distances downstream of the cascade indicates that the wake is asymmetrical and this asymmetry is maintained even up to 3/4 chord length. Experiments carried out at three incidences reveal that the decay of the wake defect is strongly dependent on the downstream variation of the wake edge velocity. For a cascade, the decay rate of the wake defect is found to be slower than that of a flat plate, cylinder or symmetrical airfoil (at zero incidence). The level of turbulence and Reynolds stresses are found to be high and some comments are made regarding self-preservation and structure of the flow. Semi-theoretical expressions are given for the wake profile, and decay of the velocity defect, turbulence intensity and Reynolds stress.

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Modeling and Simulation of Subcooled Turbulent Boiling Flow

10.1115/imece2000-1531 ◽

2000 ◽

Author(s):

J. A. Zarate ◽

R. P. Roy ◽

S. Kang ◽

Andre Laporta

Keyword(s):

Heat Flux ◽

Liquid Phase ◽

Fluid Model ◽

Turbulent Viscosity ◽

Annular Channel ◽

Momentum Equation ◽

Transfer Model ◽

Turbulent Heat ◽

Reynolds Stresses ◽

Boiling Flow

Abstract Modeling and numerical simulation of turbulent sub-cooled boiling flow of refrigerant-113 through a vertical concentric annular channel with its inner wall heated are reported. The two-fluid model conservation equations were solved. The Reynolds stresses in the liquid phase momentum equation were closed using the gradient transport approximation. The turbulent viscosity was considered to be comprised of shear-induced and bubble-induced components. Boiling at the inner wall was described by a wall heat transfer model which splits the wall heat flux into convective, quenching, and vaporization heat flux components. This model was modified to reflect our measurement of the radial turbulent heat flux in the liquid phase near the wall. In addition, new wall laws for the liquid phase mean temperature and axial velocity were used. The computational results are compared with our measurements wherever possible.

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