Transport Phenomena in Zonal Centrifuge Rotors. VII. Two-Dimensional Transient Flow Patterns and Shear Stress Distributions

The equations of mean motion indicate that two-dimensional turbulent wakes, when subjected to appropriately tailored adverse pressure gradients, can be self-preserving. An experimental examination of two nearly self-preserving wakes is reported here. Mean velocity, longitudinal and lateral turbulence intensity, inter-mittency and shear stress distributions have been measured and are compared with Townsend's data from the small-deficit undistorted wake. In comparison with the undistorted case, the present wakes have slightly lower turbulent intensities and significantly lower shear stresses, all quantities being non-dimensionalized by a local velocity scale taken as the maximum mean velocity deficit. A consideration of the reasons for the shear stress reduction leads to an expression from which the shear stresses in any symmetrical free equilibrium shear flow can be found. This relationship is used to calculate the rate of growth in the measured wakes, with reasonable success.

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An exact solution to the two-dimensional elasticity problem with rectangular boundaries under arbitrary edge forces

Philosophical Transactions of the Royal Society of London Series A Physical and Engineering Sciences ◽

10.1098/rsta.1993.0051 ◽

1993 ◽

Vol 343 (1668) ◽

pp. 307-336 ◽

Cited By ~ 13

Keyword(s):

Exact Solution ◽

Shear Stress ◽

Stress Distribution ◽

Basic Problem ◽

Fundamental Problem ◽

Force Distribution ◽

Two Dimensional ◽

Stress Distributions ◽

Problem Types ◽

Full Solution

Mathieu’s approach to the fundamental problem of plane strain (but equally applicable to plane stress) with rectangular boundaries is extended so as to encompass completely arbitrary (normal and/or shear) stress distributions acting along the four edges. The method consists in breaking up the full solution into eight basic problem types which, by appropriate superposition, can be made to describe exactly the internal stress distribution arising from any imposed force distribution throughout the boundaries.

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Finite Element Analysis of Tire/Rim Interface Forces Under Braking and Cornering Loads

Tire Science and Technology ◽

10.2346/1.2139512 ◽

1992 ◽

Vol 20 (2) ◽

pp. 83-105 ◽

Cited By ~ 5

Author(s):

J. P. Jeusette ◽

M. Theves

Keyword(s):

Finite Element ◽

Shear Stress ◽

Contact Pressure ◽

Element Model ◽

Shear Stresses ◽

Detailed Knowledge ◽

Stress Distributions ◽

Element Analysis ◽

Plane Shear ◽

Normal Contact

Abstract During vehicle braking and cornering, the tire's footprint region may see high normal contact pressures and in-plane shear stresses. The corresponding resultant forces and moments are transferred to the wheel. The optimal design of the tire bead area and the wheel requires a detailed knowledge of the contact pressure and shear stress distributions at the tire/rim interface. In this study, the forces and moments obtained from the simulation of a vehicle in stationary braking/cornering conditions are applied to a quasi-static braking/cornering tire finite element model. Detailed contact pressure and shear stress distributions at the tire/rim interface are computed for heavy braking and cornering maneuvers.

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Correction: Development of a Two-Dimensional Wall Shear Stress Sensor for Wind Tunnel Applications

AIAA Scitech 2019 Forum ◽

10.2514/6.2019-2045.c1 ◽

2019 ◽

Author(s):

Brett Freidkes ◽

David A. Mills ◽

Casey Keane ◽

Lawrence S. Ukeiley ◽

Mark Sheplak

Keyword(s):

Shear Stress ◽

Wind Tunnel ◽

Wall Shear Stress ◽

Two Dimensional ◽

Stress Sensor ◽

Shear Stress Sensor ◽

Wall Shear

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The Departure from Equilibrium of Turbulent Boundary Layers

Aeronautical Quarterly ◽

10.1017/s0001925900004418 ◽

1968 ◽

Vol 19 (1) ◽

pp. 1-19 ◽

Cited By ~ 8

Author(s):

H. McDonald

Keyword(s):

Boundary Layer ◽

Shear Stress ◽

Kinetic Energy ◽

Stress Distribution ◽

Boundary Layers ◽

Turbulent Boundary Layers ◽

Two Dimensional ◽

Pressure Distributions ◽

Momentum Integral ◽

State Examination

SummaryRecently two authors, Nash and Goldberg, have suggested, intuitively, that the rate at which the shear stress distribution in an incompressible, two-dimensional, turbulent boundary layer would return to its equilibrium value is directly proportional to the extent of the departure from the equilibrium state. Examination of the behaviour of the integral properties of the boundary layer supports this hypothesis. In the present paper a relationship similar to the suggestion of Nash and Goldberg is derived from the local balance of the kinetic energy of the turbulence. Coupling this simple derived relationship to the boundary layer momentum and moment-of-momentum integral equations results in quite accurate predictions of the behaviour of non-equilibrium turbulent boundary layers in arbitrary adverse (given) pressure distributions.

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