A multilevel adaptive projection method for unsteady incompressible flow

Conference · Mon May 17 04:00:00 EDT 1993

OSTI ID:6327713

Howell, L H

There are two main requirements for practical simulation of unsteady flow at high Reynolds number: the algorithm must accurately propagate discontinuous flow fields without excessive artificial viscosity, and it must have some adaptive capability to concentrate computational effort where it is most needed. The first of these requirements is satisfied with a second-order Godunov method similar to those used for high-speed flows with shocks, and the second with a grid-based refinement scheme which avoids some of the drawbacks associated with unstructured meshes. These two features of the author's algorithm place certain constraints on the projection method used to enforce incompressibility. Velocities are cell-based, leading to a Laplacian stencil for the projection which decouples adjacent grid points. The author discusses features of the multigrid and multilevel iteration schemes required for solution of the resulting decoupled problem. Variable-density flows require use of a modified projection operator -- a multigrid method has been found for this modified projection that successfully handles density jumps of thousands to one. Numerical results are shown for the 2D adaptive and 3D variable-density algorithms.

• Research Organization: Lawrence Livermore National Lab., CA (United States)
• Sponsoring Organization: DOE; DOD; USDOE, Washington, DC (United States); Department of Defense, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6327713
• Report Number(s): UCRL-JC-112327; CONF-9304164--1; ON: DE93016418; CNN: Agreement IACR0 93-817
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400 -- Engineering-- Heat Transfer & Fluid Flow
661300* -- Other Aspects of Physical Science-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics & Computers
ALGORITHMS
COMPUTERIZED SIMULATION
FLUID FLOW
INCOMPRESSIBLE FLOW
MATHEMATICAL LOGIC
REYNOLDS NUMBER
SIMULATION
UNSTEADY FLOW
VISCOSITY