Numerical simulation of 1‐D incompressible laminar micro‐flow convection behaviour with temperature dependent fluid properties

This paper investigates the qualitative behaviour of single‐phase laminar convection for microchannels and conventionallysized channels formed between two parallel plates, captured by a numerical simulation on water flow. The convection parameters are obtained by separate numerical calculations on a series of parallel plates at constant temperatures. The pairs of parallel plates are maintained at progressively greater temperatures, to simulate the condition of increasing fluid temperature in a channel. The governing one‐dimensional (1‐D) momentum and energy equations are formulated to incorporate the dependence on temperature of both fluid viscosity ( μ ) and thermal conductivity ( k ). The qualitative behaviour of Nusselt number ( Nu ) decreasing with increasing Reynolds number ( Re ), exhibited by reported experimental data in literature, is simulated. Results show that it is practically dif_cult to observe this behaviour in the conventionally‐sized channels, but the effect easily surfaces in microchannels for practical lengths of flow and allowable high heat flux ( q ″ W ). (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)