Parallel Large Eddy Simulation Technique using Tetrahedral Finite Elements : 2nd Report, Application to Heat Transfer Problems at High Rayleigh Number

• Published in: Transactions of the Japan Society of Mechanical Engineers Series B Vol. 68; no. 667; pp. 672 - 679
• Main Authors: KAIHO, Masayuki, MORI, Hideaki, IKEGAWA, Masahiro, KATO, Chisachi
• Format: Journal Article
• Language: Japanese
• Published: The Japan Society of Mechanical Engineers 25.03.2002
• Subjects: Heat Transfer
• ISSN: 0387-5016; 1884-8346
• DOI: 10.1299/kikaib.68.672

A parallel LES technique for viscous incompressible flow with heat transfer based on the finite-element method using tetrahedral elements has been developed. It uses an algorithm based on the SIMPLER method to solve the Navier-Stokes equations, in which a BTD term is introduced to ensure computational stability. In this technique, the Crank-Nicholson method is used as a time integration scheme to improve the accuracy to solve both the Navier-Stokes equations and the energy equation. Moreover, the Smagorinsky model is applied to approximate the Reynolds stress term and the zero-equation model is applied to solve the energy equation. The code based on this technique is parallelized by using mesh partitioning by finite elements in order to carry out the element-based calculations and by using row-based domain decomposition of the global matrix to solve the linear equations. The developed LES technique was verified by simulating natural convection problems in a cubic cavity at Ra=103 to 1010. Numerical results at Ra=103 to 108 agree well with those computed by other researchers and successfully demonstrated the stable prediction of the unsteadiness and the heat transfer at Ra=109 to 1010. It was also applied to a realistic heat transfer probelm in a rotating cavity. Computed heat transfer coefficients at Ra=1.09×109 and 2.18×109 were found to be within 15% of those measured experimentally. This acceptable error means that the new LES technique can be applited to solve heat tranfer problems in a rotating flow -field.