Transient conjugated heat transfer in channel flows with convection from the ambient

Abstract

This study presents a numerical solution of the transient conjugated heat transfer in a channel flow with convection from the ambient. The solution takes wall conduction and heat capacity effects into consideration. The effects of wall-to-fluid conductivity ratio K, the dimensionless wall thickness β, the wall-to-fluid thermal diffusivity ratio A and the outside Nusselt number Nu o on the interfacial heat flux, interfacial and bulk temperatures are discussed in detail. Results show that wall effect plays a significant role in the transient conjugated heat transfer problem. Particularly, the wall-to-fluid thermal diffusivity ratio A has a decisive effect with regard to the speed of propagation of thermal energy from the wall-fluid interface to the outer surface of the channel. In addition, the time required for heal transfer to reach the steady state condition is longer for systems with larger K and β or smaller A and Nu o.