Time‐dependent natural convection in a square cavity: Application of a new finite volume method

A new finite volume (FV) approach with adaptive upwind convection is used to predict the two-dimensional unsteady flow in a square cavity. The fluid is air and natural convection is induced by differentially heated vertical walls. The formulation is made in terms of the vorticity and the integral velocity (induction) law. Biquadratic interpolation formulae are used to approximate the temperature and vorticity fields over the finite volumes, to which the conservation laws are applied in integral form. Image vorticity is used to enforce the zero-penetration condition at the cavity walls. Unsteady predictions are carried sufficiently forward in time to reach a steady state. Results are presented for a Prandtl number (Pr) of 0-71 and Rayleigh numbers equal to 103, 104 and 105. Both 11 × 11 and 21 × 21 meshes are used. The steady state predictions are compared with published results obtained using a finite difference (FD) scheme for the same values of Pr and Ra and the same meshes, as well as a numerical bench-mark solution. For the most part the FV predictions are closer to the bench-mark solution than are the FD predictions.

[1]  K. E. Torrance,et al.  Upstream-weighted differencing schemes and their application to elliptic problems involving fluid flow , 1974 .

[2]  Timothy Nigel Phillips,et al.  Natural convection in an enclosed cavity , 1984 .

[3]  S. Patankar Numerical Heat Transfer and Fluid Flow , 2018, Lecture Notes in Mechanical Engineering.

[4]  G. D. Davis Natural convection of air in a square cavity: A bench mark numerical solution , 1983 .

[5]  Robert L. Lee,et al.  Don''t suppress the wiggles|they''re telling you something! Computers and Fluids , 1981 .

[6]  A. Jameson,et al.  A finite volume method for transonic potential flow calculations , 1977 .

[7]  P. Luchini An adaptive-mesh finite-difference solution method for the Navier-Stokes equations , 1987 .

[8]  R. Kinney,et al.  Unsteady viscous flow over a grooved wall: A comparison of two numerical methods , 1988 .

[9]  R. Kinney,et al.  A new finite‐volume approach with adaptive upwind convection , 1988 .

[10]  G. Merker,et al.  Advanced numerical computation of two-dimensional time-dependent free convection in cavities , 1980 .

[11]  H. Schlichting Boundary Layer Theory , 1955 .

[12]  G. de Vahl Davis,et al.  An evaluation of upwind and central difference approximations by a study of recirculating flow , 1976 .

[13]  A. J. Baker,et al.  Finite element computational fluid mechanics , 1983 .

[14]  A. Borthwick Comparison between two finite‐difference schemes for computing the flow around a cylinder , 1986 .

[15]  V. Denny,et al.  On the convergence of numerical solutions for 2-D flows in a cavity at large Re , 1979 .