Influence of heat conduction in the wall on nucleate boiling heat transfer

摘要

On the basis of a single bubble model on heat transfer in a wedge shaped micro region the influence of heat conduction in the wall on heat transfer in nucleate boiling is studied. The wall thermal conductivity λw is varied, whereas all other parameters, particularly the bubble site density, are kept constant. Wall conductivity is set to the values of copper, stainless steel and a ceramic material. The results of the parameter study show that even large variations of λw have only moderate influence on heat transfer to a growing vapour bubble. Simulation results for various boiling liquids are then compared with experimental data of others to test the model and examine the influence of liquid properties upon boiling heat transfer. Although the model is based on some simplifying assumptions and thus not all heat transfer mechanisms can be described in detail, the boiling curve can be predicted in the nucleate boiling regime with good accuracy for low to moderate heat fluxes.