Home > Sample Problems > Laminar Flow Past a Cylinder (Multiblock)
Laminar
Flow Past a Cylinder (Multi-block)
Same as the Laminar Flow past a Cylinder problem, except that two overset blocks are used to solve the problem.
Computational Procedure
The computational domain is composed of two blocks, each encompassing half of the cylinder¡¯s surface. The blocks are arranged such that one block contains the leading edge of the cylinder ¨C the part exposed to the free stream while the other block contains the wake region. The blocks are of different sizes. The first block is 106 ´ 64 ´ 3 grid points and the other block has 106 ´ 72 ´ 3 grid points. The blocks are shown in Figure P6.1(a).
The computational mesh is set up with graded elements close to the wall in the normal direction. The computational mesh is shown in Figure P6.1(a). The initial conditions are as follows:
Obtain the Files
Both mesh files and project input files can be accessed below. Remember to place the grid files in a subfolder with the set up file /cylinderm.
Setup file (cylinderm.afl)
Grid file (mesh0.plot3D, mesh1.plot3D or mesh0.AEROFLO, mesh1.AEROFLO).
Start the Simulation
Change the directory to the subfolder with the set up file. Start the simulation by
mpirun ¨Cnp 2 mpiaeroflo.exe< cylinderm.afl
Results
Steady-state results were obtained after the non-dimensional time reached approximately 130. Figure P6.1(a) is a close-up of the mesh of the computational domain showing the overset nodes flagged. The overset node consists of three nodes at the boundary to maintain the high order of the procedure at the interblock interface.
(a) (b)
Figure P6.1 (a) Mesh showing the flagged overset nodes
at the boundaries of the two blocks, (b) Pressure contour lines in the vicinity
of the overlap region
References:
White, F. M., ¡°Viscous Fluid Flow¡±, 2nd Ed., McGraw-Hill, 1991. pp 8-11.