Progress in the three-dimensional DRAGON grid scheme

An incompressible viscous fluid flow with heat transfer over a spherical object inside a pipe is considered. The flow is made three-dimensional by an eccentric positioning of the sphere inside the pipe. The governing equations are solved by a numerical method which uses a finite volume formulation in a generalized body fitted coordinate system. An overset (Chimera) grid scheme is used to resolve the two geometries of the pipe and sphere. The results are compared to those of an external flow over a sphere, and the code is validated using such results in the intermediate Reynolds number range. The blockage effects are analyzed through evaluation of lift, drag, and heat transfer rate over the sphere. Also the change in the shear stress pattern is examined through evaluation of the local friction factor on a pipe wall and sphere surface.

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Three-dimensional calculations of the simple shear flow around a single particle between two moving walls

Journal of Fluid Mechanics ◽

10.1017/s002211209500231x ◽

1995 ◽

Vol 283 ◽

pp. 273-285 ◽

Cited By ~ 38

Author(s):

H. Nirschl ◽

H. A. Dwyer ◽

V. Denk

Keyword(s):

Reynolds Number ◽

Shear Flow ◽

Simple Shear ◽

Particle Surface ◽

Three Dimensional ◽

Reynolds Numbers ◽

Rigid Sphere ◽

Simple Shear Flow ◽

Number Range ◽

Grid Scheme

Three-dimensional solutions have been obtained for the steady simple shear flow over a spherical particle in the intermediate Reynolds number range 0.1 [les ] Re [les ] 100. The shear flow was generated by two walls which move at the same speed but in opposite directions, and the particle was located in the middle of the gap between the walls. The particle-wall interaction is treated by introducing a fully three-dimensional Chimera or overset grid scheme. The Chimera grid scheme allows each component of a flow to be accurately and efficiently treated. For low Reynolds numbers and without any wall influence we have verified the solution of Taylor (1932) for the shear around a rigid sphere. With increasing Reynolds numbers the angular velocity for zero moment for the sphere decreases with increasing Reynolds number. The influence of the wall has been quantified with the global particle surface characteristics such as net torque and Nusselt number. A detailed analysis of the influence of the wall distance and Reynolds number on the surface distributions of pressure, shear stress and heat transfer has also been carried out.

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Validation of a Hybrid Grid Scheme of DSMC in Simulating Three-Dimensional Rarefied Gas Flows

10.1063/1.1581573 ◽

2003 ◽

Cited By ~ 2

Author(s):

Hongli Liu

Keyword(s):

Rarefied Gas ◽

Three Dimensional ◽

Gas Flows ◽

Rarefied Gas Flows ◽

Grid Scheme ◽

Hybrid Grid

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Application of a solution adaptive grid scheme to complex three-dimensional flows

AIAA Journal ◽

10.2514/3.11209 ◽

1992 ◽

Vol 30 (9) ◽

pp. 2227-2233 ◽

Cited By ~ 10

Author(s):

Carol B. Davies ◽

Ethiraj Venkatapathy

Keyword(s):

Three Dimensional ◽

Adaptive Grid ◽

Grid Scheme

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An Efficient Two-Grid Scheme for the Cahn-Hilliard Equation

Communications in Computational Physics ◽

10.4208/cicp.231213.100714a ◽

2014 ◽

Vol 17 (1) ◽

pp. 127-145 ◽

Cited By ~ 13

Author(s):

Jie Zhou ◽

Long Chen ◽

Yunqing Huang ◽

Wansheng Wang

Keyword(s):

Mixed Finite Element ◽

Three Dimensional ◽

Grid Method ◽

Mixed Finite Element Method ◽

Fine Grid ◽

Poisson Equations ◽

Hilliard Equation ◽

Grid Scheme ◽

Speed Up ◽

Cahn Hilliard Equation

AbstractA two-grid method for solving the Cahn-Hilliard equation is proposed in this paper. This two-grid method consists of two steps. First, solve the Cahn-Hilliard equation with an implicit mixed finite element method on a coarse grid. Second, solve two Poisson equations using multigrid methods on a fine grid. This two-grid method can also be combined with local mesh refinement to further improve the efficiency. Numerical results including two and three dimensional cases with linear or quadratic elements show that this two-grid method can speed up the existing mixed finite method while keeping the same convergence rate.

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