Numerical prediction of natural convection occurring in building components: A double-population lattice Boltzmann method

In this article, a double-population thermal lattice Boltzmann method is proposed to solve the problem of the heated cavity with imposed temperatures. This family of problems can be considered as a test model for building physics application. A Taylor series expansion- and least-square-based lattice Boltzmann method (TLLBM) has been implemented in order to use a non-uniform mesh. This allowed us to investigate, at reasonable computational cost, the laminar and transitional flow fields (10(3) <= Ra <= 10(8)). The numerical results, concerning the heat and mass transfers in the cases tested, are in good agreement with those from the literature. In order to demonstrate the possibilities of the method described in the article, applications are described covering double-skin facades and solar collectors or local heaters.