Prandtl Number Dependency on Transient Natural Convection in a Horizontal Enclosure of Fluid with Adiabatic Body
This study of natural convection uses the following geometry: a horizontal enclosure of fluid heated from bottom wall and cooled from above. Three different Prandtl numbers are considered to investigate the Prandtl number dependency in natural convection; 0.01, 0.7 and 7. Adiabatic boundary conditions are employed in the horizontal direction. A two-dimensional solution for unsteady natural convection is obtained, using an accurate and efficient Chebyshev spectral methodology, for different Rayleigh numbers, Ra varying over the range of 104 to 107. Multi-domain technique is used to handle a square-shaped adiabatic body. As Rayleigh number increases, the dependency of Prandtl number becomes important and affects whether the flow fields reach a steady state. The variation of time-and surface-averaged Nusselt numbers on the hot and cold walls for different Rayleigh numbers and thermal boundary conditions are also presented to show the overall heat transfer characteristics in the system.
Natural convection Nusselt number Prandtl number Spectral method
Jae Ryong Lee
Korea Atomic Energy Research Institute 1045 Daedeok-daero, Yuseong-gu, Daejeon, 305-353, South Korea
国际会议
上海
英文
1399-1411
2010-10-10（万方平台首次上网日期，不代表论文的发表时间）