The dynamic characteristics of the pressure and velocity fields of the unsteady incompressible laminar wake behind a circular cylinder are investigated numerically and analysed physically. The governing equations, written in a velocity—pressure formulation and in conservative form, are solved by a predictor—corrector pressure method, a finite-volume second-order-accurate scheme and an alternating-direction-implicit (ADI) procedure. The initiation mechanism for vortex shedding and the evaluation of the unsteady body forces are presented for Reynolds-number values of 100, 200 and 1000.The vortex shedding is generated by a physical perturbation imposed numerically for a short time. The flow transition becomes periodic after a transient time interval. The frequency of the drag and lift oscillations agree well with the experimental data.The study of the interactions of the unsteady pressure and velocity fields shows the phase relations between the pressure and velocity, and the influence of different factors: the strongly rotational viscous region, the convection of the eddies and the almost inviscid flow.The interactions among the different scales of structures in the near wake are also studied, and in particular the time-dependent evolution of the secondary eddies in relation to the fully developed primary ones is analysed.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022112086003014

Numerical study and physical analysis of the pressure and velocity fields in the near wake of a circular cylinder

Numerical solutions have been obtained for steady viscous flow past a circular cylinder at Reynolds numbers up to 300. A new technique is proposed for the boundary condition at large distances and an iteration scheme has been developed, based on Newton's method, which circumvents the numerical difficulties previously encountered around and beyond a Reynolds number of 100. Some new trends are observed in the solution shortly before a Reynolds number of 300. As vorticity starts to recirculate back from the end of the wake region, this region becomes wider and shorter. Other flow quantities like position of separation point, drag, pressure and vorticity distributions on the body surface appear to be quite unaffected by this reversal of trends.

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A numerical study of steady viscous flow past a circular cylinder

Block-implicit multigrid solution of Navier-Stokes equations in primitive variables

Driven cavity flows by efficient numerical techniques

Flow past a circular cylinder at Reynolds numbers up to 160 is simulated using high resolution calculations. Flow quantities at the cylinder surface are obtained and compared with those from the existing experimental and numerical studies. The present study reports the detailed information of flow quantities on the cylinder surface at low Reynolds numbers.

Shih-yu Tuann

Papers

Numerical studies of the flow around a circular cylinder by a finite element method

Review of computing methods for recirculating flows

New finite element results for the square cavity

A transient finite element solution method for the Navier-Stokes equations