INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDSInt. J. Numer. Meth. Fluids 2002; 40:953–980 (DOI: 10.1002/!d.395)Computational predictability of time-dependent naturalconvection !ows in enclosures(including a benchmark solution)1;!;† 2 3Mark A. Christon , Philip M. Gresho and Steven B. Sutton1Sandia National Laboratories M=S 0819; P.O. Box 5800; Albuquerque; NM 87185-0819, U.S.A.2Lawrence Livermore National Laboratory (retired); L-103; P.O. Box 808; Livermore; CA 94550; U.S.A.3Lawrence Livermore National Laboratory; L-463; P.O. Box 808; Livermore; CA 94450; U.S.A.SUMMARYThis paper summarizes the results from a special session dedicated to understanding the !uid dynamicsof the 8:1 thermally driven cavity which was held at the First MIT Conference on ComputationalFluid and Solid Dynamics in June, 2001. The primary objectives for the special session were to:(1) determine the most accurate estimate of the critical Rayleigh number above which the !ow isunsteady, (2) identify the correct, i.e. best time-dependent benchmark solution for the 8:1 di"erentiallyheated cavity at particular values of the Rayleigh and Prandtl numbers, and (3) identify those methodsthat can reliably provide these results. Copyright ? 2002 John Wiley & Sons, Ltd.KEY WORDS: 8:1 thermally driven cavity; CFD; Boussinesq equations; incompressible !ow1. INTRODUCTION AND BACKGROUNDModern thermal design practices often rely on a ‘predictive’ simulation ...