Solution of the surface Euler equations for accurate three-dimensional boundary-layer analysis of aerodynamic configurations

1987 ◽  
Author(s):  
V. IYER ◽  
J. HARRIS
Keyword(s):  
Boundary Layer ◽  
Euler Equations ◽  
Three Dimensional ◽  
Boundary Layer Analysis ◽  
Layer Analysis ◽  
Dimensional Boundary

Calculation of Three-Dimensional Boundary Layers on Rotating Turbine Blades

1987 ◽  
Vol 109 (1) ◽  
pp. 41-49 ◽  
Author(s):  
O. L. Anderson
Keyword(s):  
Heat Transfer ◽  
Boundary Layer ◽  
Turbine Blades ◽  
Three Dimensional ◽  
Pressure Surface ◽  
Boundary Layer Analysis ◽  
Layer Analysis ◽  
Edge Conditions ◽  
Dimensional Boundary ◽  
Pressure Suction

An assessment has been made of the applicability of a three-dimensional boundary-layer analysis to the calculation of heat transfer and streamline flow patterns on the surfaces of both stationary and rotating turbine passages. In support of this effort, an analysis has been developed to calculate a general nonorthogonal surface coordinate system for arbitrary three-dimensional surfaces and also to calculate the boundary-layer edge conditions for compressible flow using the surface Euler equations and experimental pressure distributions. Using available experimental data to calibrate the method, calculations are presented for the endwall, and suction surfaces of a stationary cascade and for the pressure surface of a rotating turbine blade. The results strongly indicate that the three-dimensional boundary-layer analysis can give good predictions of the flow field and heat transfer on the pressure, suction, and endwall surfaces in a gas turbine passage.

A Quasi-Three-Dimensional Blade Surface Boundary Layer Analysis for Rotating Blade Rows

1982 ◽  
Vol 104 (2) ◽  
pp. 439-449 ◽  
Author(s):  
W. T. Thompkins ◽  
W. J. Usab
Keyword(s):  
Boundary Layer ◽  
Three Dimensional ◽  
Normal Vector ◽  
Surface Boundary ◽  
Nasa Lewis Research ◽  
Surface Boundary Layer ◽  
Boundary Layer Analysis ◽  
Rotating Blade ◽  
Layer Analysis ◽  
Coordinate Lines

A quasi-three-dimensional, finite difference boundary layer analysis for rotating blade rows has been developed which uses pressure distribution and streamline position data from a three-dimensional Euler equation solver. This analysis uses as coordinate lines the blade normal vector, the local inviscid streamline direction and a crossflow coordinate tine perpendicular to both normal and streamline coordinate lines. The equations solved may be determined either by assuming the crossflow velocity to be small or that its variation in the crossflow direction is small. Thus the analysis would not apply to a region where the boundary layer character changes rapidly such as a corner but could be expected to provide good results away from hub or tip casing boundary layers. Modified versions of Keller’s box scheme are used to solve the streamwise and crossflow momentum equations as well as the energy equation. Results are presented for a high-tip speed, low aspect ratio rotor designed by NASA Lewis Research Center which show that the three-dimensional boundary layer separates significantly sooner and has a much larger influence on rotor performance than would be expected from a two-dimensional analysis.

Islands in three-dimensional steady flows

1991 ◽  
Vol 227 ◽  
pp. 527-542 ◽  
Author(s):  
C. C. Hegna ◽  
A. Bhattacharjee
Keyword(s):  
Boundary Layer ◽  
Classical Theory ◽  
Three Dimensional ◽  
Rational Surface ◽  
Steady Flows ◽  
Rational Surfaces ◽  
Boundary Layer Analysis ◽  
Layer Analysis ◽  
Euler Flows ◽  
Critical Layers

We consider the problem of steady Euler flows in a torus. We show that in the absence of a direction of symmetry the solution for the vorticity contains δ-function singularities at the rational surfaces of the torus. We study the effect of a small but finite viscosity on these singularities. The solutions near a rational surface contain cat's eyes or islands, well known in the classical theory of critical layers. When the islands are small, their widths can be computed by a boundary-layer analysis. We show that the islands at neighbouring rational surfaces generally overlap. Thus, steady toroidal flows exhibit a tendency towards Beltramization.

scholarly journals Boundary layer analysis and heat transfer of a nanofluid

2014 ◽  
Vol 17 (2) ◽  
pp. 401-412 ◽  
Author(s):  
M. M. MacDevette ◽  
T. G. Myers ◽  
B. Wetton
Keyword(s):  
Heat Transfer ◽  
Boundary Layer ◽  
Boundary Layer Analysis ◽  
Layer Analysis

An Assessment of Three-Dimensional Turbulent Boundary Layer Prediction Methods

1973 ◽  
Vol 95 (3) ◽  
pp. 415-421 ◽  
Author(s):  
A. J. Wheeler ◽  
J. P. Johnston
Keyword(s):  
Boundary Layer ◽  
Eddy Viscosity ◽  
Three Dimensional ◽  
High Sensitivity ◽  
Boundary Layer Flows ◽  
Mean Velocity ◽  
Eddy Viscosity Model ◽  
Separating Flow ◽  
Dimensional Boundary ◽  
Stress Models

Predictions have been made for a variety of experimental three-dimensional boundary layer flows with a single finite difference method which was used with three different turbulent stress models: (i) an eddy viscosity model, (ii) the “Nash” model, and (iii) the “Bradshaw” model. For many purposes, even the simplest stress model (eddy viscosity) was adequate to predict the mean velocity field. On the other hand, the profile of shear stress direction was not correctly predicted in one case by any model tested. The high sensitivity of the predicted results to free stream pressure gradient in separating flow cases is demonstrated.

Experimental and Theoretical Investigation of the Supersonic Boundary Layer Stability on the Swept Wing

2008 ◽  
Vol 3 (3) ◽  
pp. 34-38
Author(s):  
Sergey A. Gaponov ◽  
Yuri G. Yermolaev ◽  
Aleksandr D. Kosinov ◽  
Nikolay V. Semionov ◽  
Boris V. Smorodsky
Keyword(s):  
Boundary Layer ◽  
Three Dimensional ◽  
Leading Edge ◽  
Supersonic Boundary Layer ◽  
Mean Flow ◽  
Swept Wing ◽  
Wing Model ◽  
Dimensional Boundary ◽  
The Stability ◽  
Good Agreement

Theoretical and an experimental research results of the disturbances development in a swept wing boundary layer are presented at Mach number М = 2. In experiments development of natural and small amplitude controllable disturbances downstream was studied. Experiments were carried out on a swept wing model with a lenticular profile at a zero attack angle. The swept angle of a leading edge was 40°. Wave parameters of moving disturbances were determined. In frames of the linear theory and an approach of the local self-similar mean flow the stability of a compressible three-dimensional boundary layer is studied. Good agreement of the theory with experimental results for transversal scales of unstable vertices of the secondary flow was obtained. However the calculated amplification rates differ from measured values considerably. This disagreement is explained by the nonlinear processes observed in experiment

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