
Accession Number : ADA289937
Title : Numerical Experiments on the Flow Past a Circular Cylinder at SubCritical Reynolds Number,
Corporate Author : STANFORD UNIV CA THERMOSCIENCES DIV
Personal Author(s) : Beaudan, Patrick ; Moin, Parviz
PDF Url : ADA289937
Report Date : DEC 1994
Pagination or Media Count : 262
Abstract : The performance of the dynamic subgridscale eddyviscosity model and the suitability of highorder accurate, upwindbiased numerical methods for large eddy simulations of complex flows are investigated in the case of the turbulent wake behind a circular cylinder at Reynolds number 3,900, based on freestream velocity and cylinder diameter. The numerical method consists of highorder upwindbiased finite difference techniques applied to the compressible NavierStokes equations written in generalized coordinates. Integration in time is done using a fully implicit, secondorder accurate iterative technique. The results of three fifthorder accurate simulations performed on identical grids with the leastsquares version of the dynamic model, the fixedcoefficient Smagorinsky model, and with no subgridscale model are compared in the first 10 diameters of the wake. The impact of threedimensionality is also examined via two and threedimensional calculations without a subgridscale model. The effect of numerical dissipation is investigated by comparing two simulations using upwindbiased schemes, the first being fifthorder, and the second seventhorder accurate. It is found that the nearwake is highly threedimensional at this Reynolds number. It contains pairs of counterrotating streamwise vortices, the effect of which cannot be reproduced in twodimensional calculations. Threedimensional computations are essential for predicting flow statistics of engineering interest. (AN)
Descriptors : *EDDIES(FLUID MECHANICS), *COMPUTATIONAL FLUID DYNAMICS, *VISCOUS FLOW, VELOCITY, MATHEMATICAL MODELS, COMPUTERIZED SIMULATION, EXPERIMENTAL DATA, GRIDS, BOUNDARY LAYER, DISSIPATION, TURBULENCE, VORTEX SHEDDING, THREE DIMENSIONAL, FINITE DIFFERENCE THEORY, COMPRESSIBLE FLOW, CYLINDRICAL BODIES, WAKE, NUMERICAL METHODS AND PROCEDURES, HEAT FLUX, NAVIER STOKES EQUATIONS, FREE STREAM, BIAS, LAMINAR FLOW, REYNOLDS NUMBER.
Subject Categories : Fluid Mechanics
Distribution Statement : APPROVED FOR PUBLIC RELEASE