Natural convection flow in a vertical micro-annulus with time-periodic thermal boundary conditions

Abstract

Purpose The purpose of this paper is to investigate the impact of time-periodic thermal boundary conditions on natural convection flow in a vertical micro-annulus. Design/methodology/approach Analytical solution in terms of Bessel’s function and modified Bessel’s function of order 0 and 1 is obtained for velocity, temperature, Nusselt number, skin friction and mass flow rate. Findings It is established that the role of Knudsen number and fluid–wall interaction parameter is to decrease fluid temperature, velocity, Nusselt number and skin friction. Research limitations/implications No laboratory practical or experiment was conducted. Practical implications Cooling device in electronic panels, card and micro-chips is frequently cooled by natural convection. Originality/value In view of the amount of works done on natural convection in microchannel, it becomes interesting to investigate the effect that time-periodic heating has on natural convection flow in a vertical micro-annulus. The purpose of this paper is to examine the impact of time-periodic thermal boundary conditions on natural convection flow in a vertical micro-annulus.