An alternative to heat transfer coefficient: A relevant model of heat transfer between a developed fluid flow and a non-isothermal wall in the transient regime

摘要

This paper deals with the relevant model that can be proposed for modelling interface heat transfer between a fluid and a wall for thermal boundary conditions varying in space and time. Usually, for a constant and uniform heat transfer (unidirectional steady-state regime), the problem can be solved through the introduction of the notion of a h heat transfer coefficient. This quantity, which is uniform in space and constant in time, links heat flux to a temperature difference (between the wall temperature T-w and an equivalent fluid temperature T-f, where h and T-f both depend on the system geometry) in a linear way.