Note on an integral equation of viscous flow theory

Under sustained loads with a fixed value, the deformation of concrete will continue to increase as time increases; this phenomenon is called creep of concrete. Currently, there are several theories to explain the phenomenon of concrete creep, viscoelasticity theory, seepage theory, viscous flow theory, plastic flow theory, micro-fractures theory and internal forces balance theory. Above models mostly studied linear creep of concrete under low stress status. This paper mainly research on concrete creep mechanism, and pointed out the advantages and limitations of the various theories, which has a guiding significance for theoretical research.

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Inverse design of axisymmetric flow passages using compressible viscous flow theory

Communications in Applied Numerical Methods ◽

10.1002/cnm.1630020112 ◽

1986 ◽

Vol 2 (1) ◽

pp. 83-89 ◽

Cited By ~ 1

Author(s):

Francois Ntone ◽

Tah-Teh Yang

Keyword(s):

Viscous Flow ◽

Axisymmetric Flow ◽

Flow Theory ◽

Inverse Design

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Impulsive Motion of a Moving Circular Cylinder in a Viscous Flow by the Numerical Simulation

Journal of Mechanics ◽

10.1017/s1727719100000149 ◽

1998 ◽

Vol 14 (3) ◽

pp. 119-123

Author(s):

D. L. Young ◽

J. T. Chang

Keyword(s):

Circular Cylinder ◽

Viscous Fluid ◽

Viscous Flow ◽

Drag Force ◽

Moving Boundary ◽

Stokes Equations ◽

Flow Theory ◽

Infinite Domain ◽

Constant Acceleration ◽

Element Method

ABSTRACTAn innovative computation procedure is developed to solve the external flow problems for viscous fluids. The method is able to handle the infinite domain so that it is convenient for the external flows. The code is based on the projection method of the Navier-Stokes equations. We use the three-step explicit finite element method to solve the momentum equation by extracting the boundary effects from the finite computation domain. The pressure Poisson equation for the external field is treated by the boundary element method. The arbitrary Lagrangian-Eulerian (ALE) scheme is employed to incorporate the present algorithm to deal with the moving boundary, such as the motion of an impulsively moving circular cylinder in a viscous fluid. The model demonstrates that drag force is well predicted for a circular cylinder moving in a still viscous fluid starting from rest, to a constant acceleration, and then maintaining at a uniform velocity. In the constant acceleration phase, the drag force is closed to the added mass effect from the ideal flow theory. On the other hand, the drag force is equal to viscous flow theory in the constant velocity phase.

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