Study of pool boiling heat transfer of nanofluid in the PCD electrical fields

Abstract

Nanofluids with excellent thermal properties can be used for a coolant and the heat exchange. Actually, the heat transfer between the nanoparticles and working medium benefits from the nanoparticles movement, which could be controlled actively by the electrical field with periodically changed direction (PCD electrical field). Therefore, the coupled effect of nanofluid and switching period and the prediction model were investigated. Concretely, the boiling heat transfer coefficient (BHTC) and the critical heat flux (CHF) with various switching periods of the electrical field were compared. Meanwhile, the mechanism of heat transfer enhancement was discussed. Besides, the predicted model was developed. The present study finds that the BHTC and the CHF will be further strengthened due to the coupled effect of the PCD electrical field and nanofluid. However, this enhancement has an optimal concentration. Moreover, the heat transfer performance enhancement is attributed to the continuous heat transfer by nanoparticle and the further decrease of surface tension. The prediction curves mostly coincide with experimental data, and the prediction models are proposed by considering the influence of the switching period, the nanoparticles movement, the gas-liquid interface surface tension and the dynamic thermal conductivity.