The Effect of the Axial Velocity Density Ratio on the Aerodynamic Coefficients of Compressor Cascades

1981 ◽  
Vol 103 (1) ◽  
pp. 210-219 ◽  
Author(s):  
J. Starke
Keyword(s):  
Axial Velocity ◽  
Density Ratio ◽  
Compressor Blade ◽  
Momentum Thickness ◽  
Two Dimensional ◽  
Aerodynamic Coefficients ◽  
Minimum Loss ◽  
Turning Angle ◽  
Two Dimensional Flow ◽  
Inlet Angle

The aerodynamic coefficients of compressor blade sections in two-dimensional flow can easily and very accurately be determined by use of the well-known Lieblein correlations. The flow across the compressor blade sections is often quasi-two-dimensional with the axial velocity density ratio (AVDR) differing from unity. To establish simple correlations for this type of flow as well, the AVDR effect on the aerodynamic coefficients of compressor cascades is theoretically and experimentally investigated. This results in simple but accurate formulae for the calculation of the AVDR effect on the turning angle, the reference minimum-loss inlet angle, and the losses in terms of the wake momentum thickness and the diffusion ratio.

scholarly journals The Effect of the Axial Velocity Density Ratio on the Aerodynamic Coefficients of Compressor Cascades

1980 ◽  
Author(s):  
J. Starke
Keyword(s):  
Axial Velocity ◽  
Density Ratio ◽  
Compressor Blade ◽  
Momentum Thickness ◽  
Two Dimensional ◽  
Aerodynamic Coefficients ◽  
Minimum Loss ◽  
Turning Angle ◽  
Two Dimensional Flow ◽  
Inlet Angle

The aerodynamic coefficients of compressor blade sections in two-dimensional flow can easily and very accurately be determined by use of the well-known Lieblein correlations. Very often the flow across the compressor blade sections is quasi-two-dimensional with the axial velocity density ratio (AVDR) differing from unity. To establish simple correlations for this type of flow as well, the AVDR effect on the aerodynamic coefficients of compressor cascades is theoretically and experimentally investigated. This results in simple but accurate formulas for the calculation of the AVDR effect on the turning angle, the reference minimum-loss inlet angle, and the losses in terms of the wake momentum thickness and the diffusion ratio.

Investigation of the Axial Velocity Density Ratio in a High Turning Cascade

1975 ◽  
Author(s):  
H. Starken ◽  
F. A. E. Breugelmans ◽  
P. Schimming
Keyword(s):  
Axial Velocity ◽  
Density Ratio ◽  
Two Dimensional ◽  
Flow Conditions ◽  
Circular Arc ◽  
Blade Row ◽  
Two Dimensional Flow ◽  
Blade Section ◽  
Stator Blade ◽  
Density Ratios

Subsonic cascade tests of a stator blade row are presented. A 48-deg cambered double circular arc blade section has been investigated at different inlet Mach numbers (M1 = 0.5, 0.64, 0.74), different inlet flow angles and various axial velocity density ratios. Optimum cascade performance has been obtained at negative incidence angles and near two-dimensional flow condition. The cascade results are compared with stator tests of the same blade section at corresponding flow conditions.

scholarly journals Generalized two-dimensional Lagally theorem with free vortices and its application to fluid–body interaction problems

2012 ◽  
Vol 698 ◽  
pp. 73-92 ◽  
Author(s):  
C. T. Wu ◽  
F.-L. Yang ◽  
D. L. Young
Keyword(s):  
Hydrodynamic Force ◽  
Density Ratio ◽  
Vortex Pair ◽  
The Body ◽  
Body Motion ◽  
Liquid Density ◽  
Two Dimensional ◽  
Fixed Target ◽  
Two Dimensional Flow ◽  
Neutrally Buoyant

AbstractThe Lagally theorem describes the unsteady hydrodynamic force on a rigid body exhibiting arbitrary motion in an inviscid and incompressible fluid by the properties of the singularities employed to generate the flow and the body motion and to meet the boundary condition. So far, only sources and dipoles have been considered, and the present work extends the theorem to include free vortices in a two-dimensional flow. The present extension is validated by reproducing the system dynamics or the force evolution of three literature problems: (i) a free cylinder interacting with a free vortex; (ii) the moving Föppl problem; and (iii) a cylinder in constant normal approach to a fixed identical cylinder. This work further extends the bifurcation analysis on the moving Föppl problem by including the solid-to-liquid density ratio as a new parameter, in addition to the system total impulse and the vortex strength. We then apply the theorem to the problem where a moving Föppl system is made to approach a fixed or a free neutrally buoyant target cylinder of identical size from far away. The force developed on each cylinder is examined with respect to the vortex pair configuration and the target mobility. When approaching a fixed target, a greater force is developed if the vortex pair has stronger circulation and larger structure. The mobility of the target cylinder, however, can modify the hydrodynamic force by reducing its magnitude and reversing the force ordering with respect to the vortex pair configuration found for the case with fixed target. Possible mechanisms for such a change of force nature are given based on the currently derived equation of motion.

Effect of Axial Velocity Variation in Aerofoil Cascades

1971 ◽  
Vol 13 (2) ◽  
pp. 92-99 ◽  
Author(s):  
S. Soundranayagam
Keyword(s):  
Wind Tunnel ◽  
Incompressible Flow ◽  
Axial Velocity ◽  
Three Dimensional ◽  
Velocity Variation ◽  
Two Dimensional ◽  
Dimensional Flow ◽  
Two Dimensional Flow ◽  
Wind Tunnel Data ◽  
Flow Through

The effect of the variation of axial velocity in the incompressible flow through a cascade of aerofoils is discussed and it is shown that changes take place in the flow angles and in the blade circulation. A method is proposed by which the effect of axial velocity variation on a known two-dimensional flow or alternatively the two-dimensional equivalent of a flow with axial velocity variation can be calculated. The method is very easy to apply. The deviation may increase or decrease depending on the change in blade circulation and the stagger. An increase in apparent deflection through the cascade can be accompanied by a reduction in the blade force. The method would be particularly useful for the interpretation of cascade wind tunnel data and in the design of impeller stages where three-dimensional flows occur.

Influence of Sensitive Cavity Structure on the Resolution of Fluidic Gyroscope

2012 ◽  
Vol 268-270 ◽  
pp. 1558-1561
Author(s):  
Bao Li Zhang ◽  
Lin Hua Piao ◽  
Jin Tang ◽  
Chuan Zhi Mei
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Axial Velocity ◽  
Theoretical Foundation ◽  
Flow Distribution ◽  
Rectangular Cavity ◽  
Two Dimensional ◽  
Velocity Difference ◽  
Cavity Structure ◽  
Two Dimensional Flow

The flow distribution of fluidic gyroscope with three different cavities was researched when angular velocity ωi is input. Using Finite element method we calculated two-dimensional flow distribution of fluidic gyroscope with rectangular cavity and two streamlined cavity structures when ωi input. The results show that: with ωi increasing, the fluidic beam centers in three cavities have a more deviation on one side, while in two streamlined cavities it deviates obviously. When ωi is 10rad/s, velocity difference of two thermal wires in streamlined cavity 1 and cavity 2 increase 42.59% and 59.30% respectively compared with rectangular cavity, velocity and y-axial velocity of two thermal wires in streamlined cavity 1 are smaller than rectangular cavity but larger than streamlined cavity 2, but x-axial velocity of two thermal wires in streamlined cavity 1 are smaller than other two cavities, and so is ωi = 15rad/s. It also shows that velocity difference between two thermal wires in streamlined cavity 1 is larger than others, and temperature difference is larger, which can improve the resolution of fluidic gyroscope. This article has laid a theoretical foundation to further enhance performance of fluidic gyroscopes.

Two-Dimensional Flow of Polymer Solutions Through Porous Media

1999 ◽  
Vol 2 (3) ◽  
pp. 251-262
Author(s):  
P. Gestoso ◽  
A. J. Muller ◽  
A. E. Saez
Keyword(s):  
Porous Media ◽  
Polymer Solutions ◽  
Two Dimensional ◽  
Dimensional Flow ◽  
Two Dimensional Flow

STUDY OF NON-ISOTHERMAL TWO-DIMENSIONAL FLOW OVER A SQUARE CYLINDER IMMERSED IN A CHANNEL

2019 ◽  
Author(s):  
Gabriel Machado dos Santos ◽  
Ítalo Augusto Magalhães de Ávila ◽  
Hélio Ribeiro Neto ◽  
João Marcelo Vedovoto
Keyword(s):  
Two Dimensional ◽  
Square Cylinder ◽  
Dimensional Flow ◽  
Two Dimensional Flow
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