The effects of wavy geometry on natural convection in an enclosure with two wavy vertical walls and filled with fluid saturated porous media are investigated numerically by using finite element method. The wavy enclosure is transformed to a unit square in the computational domain and the finite element formulations are solved in terms ofξη-coordinate based on iterative method. In order to investigate the effects of interested parameters, the values of wave amplitude (λ= 0.05 and 0.1) and number of undulations (n= 1 and 2) are chosen with constants Ra = 105, Da = 10−3, and Pr = 0.71. It is found that the increase in number of undulations has small effect on natural convection inside the enclosure whereas the increase in wave amplitude reduces the strength of convection because higher wave volume plays a barricade role.
Numerical study has been performed to investigate the effects of location and height for the partitions located on the bottom wall of a square enclosure filled with porous media. This study starts considering the simplest enclosure with two partitions. The partitions are non-uniformly heated. The left and the top wall are cooled while the right and the bottom wall are adiabatic well. The location and height of two partitions are considered. The interested parameters are Darcy number (Da) from 10 −5 to 10 −1 , the value of Rayleigh number(Ra) is fixed at 10 5 and the Prandtl number (P r) is 0.71. The results are presented in forms of streamlines, isotherms and heatlines. It can be found that the flow field is single cell when the height of the partitions is less than 0.5. The flow field and heat transfer increase when the value of Darcy number is increased.
The effects of various parameters, Rayleigh number (Ra), Darcy number (Da), and wave amplitude (a), on natural convection inside a trapezoidal enclosure with wavy top surface are studied. The enclosure is filled with seawater having Prandtl number (Pr) of 7.2 and uniformly heated on bottom and partially heated on inclined boundaries. The flow field and temperature distribution are observed when interested parameters are chosen for Ra = 104, 105, and 106, Da = 10−5, 10−4, and 10−3, anda=0.9, 1, and 1.1. FlexPDE, a finite element model builder, is used to solve the governing equations to obtain the numerical results displayed by streamlines and isotherms. From the study results, convection motion is affected by different parameters in which the increase in flow intensity and temperature distribution can be seen at higher Rayleigh and Darcy numbers. The wavy top surface has small influence on the flow field and temperature distribution compared to the influence of Rayleigh and Darcy numbers.
The present paper numerically studies natural convection in a partially cooled square enclosure filled with a porous medium. One of the enclosure walls is heated while the middle opposite wall is partially cooled. The remaining walls are adiabatic. The governing equations which are continuity, momentum and energy equations are solved using finite element method with FlexPDE 6.20 Professional. The relevant parameters for computations are Darcy numbers (Da = 10 −5 −10 −3 ), Rayleigh numbers (Ra = 10 4 −10 6 ), Prandtl numbers (P r = 0.70 − 10) and cold length (D = 0.50). The numerical results are present in terms of isotherms, streamlines and heatlines. It is found that varied Darcy and Rayleigh numbers can lead to difference temperature flow and heat fields. The results of this study can be use in the thermal insulation of buildings and cooling systems of electronic devices.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.