Viscous Flow in an Annulus With a Sector Cavity

1982 ◽  
Vol 104 (4) ◽  
pp. 500-504 ◽  
Author(s):  
V. O’Brien
Keyword(s):  
Biharmonic Equation ◽  
Three Dimensional ◽  
Axial Flow ◽  
Cavity Flow ◽  
Three Dimensional Flow ◽  
Circular Annulus ◽  
Dimensional Interaction ◽  
Laminar Mixing ◽  
Flow Through ◽  
Finite Difference Solution

The two-dimensional interaction of a circular shear flow and a sector cavity flow is predicted by finite-difference solution of the governing biharmonic equation for steady Stokes planar flow. The location of the dividing streamline is a function of geometry, lying perhaps wholly within the cavity or bulging up into the circular annulus. Also pressure-driven axial flow through the annular configuration is predicted by numerical solution of the governing Poisson equation. The results can be combined with the planar solution to describe a steady three-dimensional flow field which will enhance laminar mixing.

Three Dimensional Supersonic Flow Through a Cascade of Twisted Flat Plates

1980 ◽  
Vol 102 (3) ◽  
pp. 338-343
Author(s):  
C. F. Grainger
Keyword(s):  
Method Of Characteristics ◽  
Three Dimensional ◽  
Axial Flow ◽  
Finite Difference Approximation ◽  
Difference Approximation ◽  
Flat Plates ◽  
Three Dimensional Flow ◽  
Dimensional Flow ◽  
Two Dimensional Flow ◽  
Flow Through

The three-dimensional flow through a cascade of twisted flat-plate blades is calculated using a computer program based on a finite-difference approximation to the method of characteristics. The relative flow is supersonic but the axial flow is subsonic. For two-dimensional flow under similar conditions, the inlet flow field is one of “unique-incidence,” the effect discussed by Starken (5) and others. The main purpose of the present work is to extend the understanding of this effect to three-dimensional flow. Important differences between the two and three-dimensional flow fields are explained in terms of the interaction between neighboring sections of the flow.

An Experimental Arrangement for the Measurement of the Pressure Distribution on High Speed Rotating Blade Rows

1956 ◽  
Author(s):  
K. Leist
Keyword(s):  
Experimental Investigation ◽  
Pressure Distribution ◽  
High Speed ◽  
Three Dimensional ◽  
Axial Flow ◽  
Three Dimensional Flow ◽  
Research Staff ◽  
Rotating Blade ◽  
Flow Through ◽  
Turbine Blading

For several years past, the research staff of the Institute for Turbomachines of the Aachen Technical University has carried out measurements on rotating turbine blading. This program is part of a comprehensive effort directed toward the experimental investigation of the three-dimensional flow through axial-flow turbomachines.

Three-Dimensional Potential Flow and Effects of Blade Dihedral in Axial Flow Propeller Pumps

1977 ◽  
Vol 99 (1) ◽  
pp. 167-175 ◽  
Author(s):  
R. Howells ◽  
B. Lakshminarayana
Keyword(s):  
Potential Flow ◽  
Three Dimensional ◽  
Axial Flow ◽  
Three Dimensional Flow ◽  
Dimensional Flow ◽  
Pressure Distributions ◽  
Rotating Blade ◽  
Satisfactory Approximation ◽  
Flow Through ◽  
Flow Effects

A relatively simple and rapid method for predicting the three-dimensional flow effects in axial flow turbomachinery was investigated. Although the two-dimensional cascade is a satisfactory approximation for the design and analysis of some types of turbo-machines, the flow through devices, such as propeller pumps and inducers, may deviate significantly. A three-dimensional lifting surface theory was used to predict the potential flow around blades, represented by line vortices and sources, spanning an annulus. A rotor was designed, built, and tested (with air as the test medium) for comparison with the theory. Static pressure distributions on a rotating blade were measured. The effect of blade dihedral on these pressures was also measured. Deviation from cascade predictions caused by the three-dimensional flow effects is found to be appreciable for propeller pumps. No theory was developed, but variation of the experimental blade pressure distributions caused by dihedral was found to be considerable.

A Three-Dimensional Analysis of Rotor Wakes

1972 ◽  
Vol 23 (4) ◽  
pp. 285-300 ◽  
Author(s):  
C E Whitfield ◽  
J C Kelly ◽  
B Barry
Keyword(s):  
Dimensional Analysis ◽  
Constant Temperature ◽  
Three Dimensional ◽  
Axial Flow ◽  
Visual Presentation ◽  
Hot Wire ◽  
Three Dimensional Flow ◽  
Dimensional Flow

SummaryMany investigators have studied the aerodynamics of axial flow turbomachinery but none has produced a complete map of the three-dimensional flow behind a rotor row. This is of considerable interest to the aero-acoustician. A system is described which uses a constant temperature hot-wire anemometer to analyse the flow behind such a rotor. Although much information may be extracted by using the technique, its interpretation depends to a large extent on its form of presentation. An analysis of the flow behind a research fan is used as a means of discussing various forms of visual presentation.

Excess Streamwise Vorticity and Its Role in Secondary Flow

1987 ◽  
Vol 201 (6) ◽  
pp. 413-420 ◽  
Author(s):  
P W James
Keyword(s):  
Secondary Flow ◽  
Gas Turbines ◽  
Three Dimensional ◽  
Point Of View ◽  
Streamwise Vorticity ◽  
Three Dimensional Flow ◽  
Approximate Methods ◽  
Blade Row ◽  
Flow Through ◽  
Loss Term

The purpose of this paper is, firstly, to show how the concept of excess secondary vorticity arises naturally from attempts to recover three-dimensional flow details lost in passage-averaging the equations governing the flow through gas turbines. An equation for the growth of excess streamwise vorticity is then derived. This equation, which allows for streamwise entropy gradients through a prescribed loss term, could be integrated numerically through a blade-row to provide the excess vorticity at the exit to a blade-row. The second part of the paper concentrates on the approximate methods of Smith (1) and Came and Marsh (2) for estimating this quantity and demonstrates their relationship to each other and to the concept of excess streamwise vorticity. Finally the relevance of the results to the design of blading for gas turbines, from the point of view of secondary flow, is discussed.

Three-Dimensional Flow and Mixing in an Axial Flow Compressor With Different Rotor Tip Clearances

1992 ◽  
Vol 114 (3) ◽  
pp. 675-685 ◽  
Author(s):  
A. Goto
Keyword(s):  
Velocity Fluctuation ◽  
Three Dimensional ◽  
Axial Flow ◽  
Flow Fields ◽  
Tip Clearance ◽  
Small Scale ◽  
Three Dimensional Flow ◽  
Axial Flow Compressor ◽  
Dimensional Flow ◽  
Flow Compressor

The effect of difference in rotor tip clearance on the mean flow fields and unsteadiness and mixing across a stator blade row were investigated using hot-wire anemometry, pressure probes, flow visualization, and the ethylene tracer-gas technique on a single-stage axial flow compressor. The structure of the three-dimensional flow fields was discussed based on results of experiments using the 12-orientation single slanted hotwire technique and spectrum analysis of velocity fluctuation. High-pass filtered measurements of turbulence were also carried out in order to confirm small-scale velocity fluctuation, which is more realistically referred to as turbulence. The span-wise distribution of ethylene gas spreading, estimated by the measured small-scale velocity fluctuation at the rotor exit, agreed quite well with that which was experimentally measured. This fact suggests the significant role of turbulence, generated within the rotor, in the mixing process across the downstream stator. The value of the maximum mixing coefficient in the tip region was found to increase linearly as the tip clearance became enlarged, starting from the value at midspan.

Sign in / Sign up

Export Citation Format

Share Document