Showing papers by "Yutaka Asako published in 1995"
TL;DR: In this paper, a numerical study is conducted to investigate the entrance behavior of turbulent flow and heat transfer in an array of rectangular heated blocks deployed along one wall of a parallel plate duct in an in-line arrangement in an attempt to simulate the cooling passages of electronic equipment.
Abstract: A numerical study is conducted to investigate the entrance behavior of turbulent flow and heat transfer in an array of rectangular heated blocks. The blocks are deployed along one wall of a parallel plate duct in an in-line arrangement in an attempt to simulate the cooling passages of electronic equipment. The Lam-Bremhorst low-Reynolds-number form of the κ-e turbulence model is used for the computations. The computations are performed for a set of geometric parameters characterizing the array and for the conditions of constant wall temperature and uniform heat generation per module. The Reynolds numbers ranged from 2000 to 5000, with the laminar Prandtl number 0.7 and the turbulent Prandtl number 0.9. The results are presented in the form of axial velocity contours, pressure distributions, and local and averaged Nusselt numbers, and are compared with relevant experimental data.
9 citations
TL;DR: In this article, an algebraic coordinate transformation technique was used to map the hexagonal cross section onto a rectangle and then solved with a control volume discretization scheme using a fully implicit method with time.
Abstract: Unsteady three-dimensional natural convection heat transfer in an inclined air slot with a hexagonal honeycomb enclosure is investigated numerically. The numerical methodology is based on an algebraic coordinate transformation technique that maps the hexagonal cross section onto a rectangle. The transformed governing equations are solved with a control volume discretization scheme using a fully implicit method with time. The computations are performed for inclination angles in the range of 60 to 80 deg for Ra = 10{sup 4}, and in the range of 45 to 80 deg for Ra = 10{sup 5}, for Prandtl number of 0.7, and for a fixed aspect ratio of H/L = 5. A conductive thermal boundary condition for the honeycomb side walls is considered. Both periodic and nonperiodic oscillating solutions are obtained depending on the inclination angle and Rayleigh number. The complex flow patterns are presented in form of particle trajectory maps and are compared with the flow visualization results using microcapsulated liquid crystals. 17 refs., 10 figs., 2 tabs.
3 citations