Effect of Reynolds and Grashof numbers on laminar mixed convection of an isothermally heated vertical plate channel

In this paper, numerical analysis of laminar mixed convection of an isothermally heated vertical channel has been carried out using finite element method. Both of the side walls of the vertical channel are maintained at constant high temperature, whereas the inlet air follows Poiseuille’s velocity profile at cold temperature. To solve this problem, two dimensional Navier-Stokes and energy equations are considered as the governing equations. The variation of flow characteristics are obtained from fixed Grashof number (Gr = 100; Re = 10, 100, 500), fixed Reynolds number (Re = 100; Ri = 0.1, 1, 10) and fixed Richardson number (Ri = 1; Re = 10, 100, 500). The results are presented in terms of isotherms, streamlines, temperatures and velocity profiles across the channel. The results showed that the average Nusselt number on the hot walls increases with the increment of Re at constant Gr. Similar enhancement of heat transfer is observed with the decrement of Ri while Re is kept constant.