TY - JOUR
T1 - Comparison of computational codes for direct numerical simulations of turbulent Rayleigh–Bénard convection
AU - Kooij, Gijs L.
AU - Botchev, Mikhail A.
AU - Frederix, Edo M.A.
AU - Geurts, Bernardus J.
AU - Horn, Susanne
AU - Lohse, Detlef
AU - van der Poel, Erwin P.
AU - Shishkina, Olga
AU - Stevens, Richard J.A.M.
AU - Verzicco, Roberto
PY - 2018/4/30
Y1 - 2018/4/30
N2 - Computational codes for direct numerical simulations of Rayleigh–Bénard (RB) convection are compared in terms of computational cost and quality of the solution. As a benchmark case, RB convection at Ra=108 and Pr=1 in a periodic domain, in cubic and cylindrical containers is considered. A dedicated second-order finite-difference code (AFID/RBFLOW) and a specialized fourth-order finite-volume code (GOLDFISH) are compared with a general purpose finite-volume approach (OPENFOAM) and a general purpose spectral-element code (NEK5000). Reassuringly, all codes provide predictions of the average heat transfer that converge to the same values. The computational costs, however, are found to differ considerably. The specialized codes AFID/RBFLOW and GOLDFISH are found to excel in efficiency, outperforming the general purpose flow solvers NEK5000 and OPENFOAM by an order of magnitude with an error on the Nusselt number Nu below 5%. However, we find that Nu alone is not sufficient to assess the quality of the numerical results: in fact, instantaneous snapshots of the temperature field from a near wall region obtained for deliberately under-resolved simulations using NEK5000 clearly indicate inadequate flow resolution even when Nu is converged. Overall, dedicated special purpose codes for RB convection are found to be more efficient than general purpose codes.
AB - Computational codes for direct numerical simulations of Rayleigh–Bénard (RB) convection are compared in terms of computational cost and quality of the solution. As a benchmark case, RB convection at Ra=108 and Pr=1 in a periodic domain, in cubic and cylindrical containers is considered. A dedicated second-order finite-difference code (AFID/RBFLOW) and a specialized fourth-order finite-volume code (GOLDFISH) are compared with a general purpose finite-volume approach (OPENFOAM) and a general purpose spectral-element code (NEK5000). Reassuringly, all codes provide predictions of the average heat transfer that converge to the same values. The computational costs, however, are found to differ considerably. The specialized codes AFID/RBFLOW and GOLDFISH are found to excel in efficiency, outperforming the general purpose flow solvers NEK5000 and OPENFOAM by an order of magnitude with an error on the Nusselt number Nu below 5%. However, we find that Nu alone is not sufficient to assess the quality of the numerical results: in fact, instantaneous snapshots of the temperature field from a near wall region obtained for deliberately under-resolved simulations using NEK5000 clearly indicate inadequate flow resolution even when Nu is converged. Overall, dedicated special purpose codes for RB convection are found to be more efficient than general purpose codes.
KW - Heat transfer
KW - Rayleigh–Bénard convection
KW - Direct numerical simulations
UR - http://www.scopus.com/inward/record.url?scp=85041475622&partnerID=8YFLogxK
U2 - 10.1016/j.compfluid.2018.01.010
DO - 10.1016/j.compfluid.2018.01.010
M3 - Article
AN - SCOPUS:85041475622
VL - 166
SP - 1
EP - 8
JO - Computers and fluids
JF - Computers and fluids
SN - 0045-7930
ER -