Numerical investigation on heat and mass transfer characteristics of ice slurry in pulsating flow

Abstract

In this paper, the heat transfer enhancement of ice slurry in a horizontal pipe with constant heat flux has been investigated numerically. The model is validated with the experimental results from the literature. Then the axial distribution of the heat transfer coefficient, the bulk and wall temperature and the ice volume fraction are obtained. The factors that affect the heat transfer coefficient are analyzed. Furthermore, the heat transfer efficiency of ice slurry in pulsating flow is compared with that in steady state. It is found that the heat transfer efficiency of ice slurry can be significantly improved by pulsating flow. The maximum increment of cycle-averaged heat transfer coefficient reaches 34.32%. Moreover, the degrees of heat transfer enhancement increase with increasing pulsating frequency, relative amplitude of velocity, ice particle diameter and ice volume fraction, and decrease with increasing cycle-averaged velocity. And the heat transfer is more efficient to ice slurry with large particles and ice volume fraction under the pulsating flow conditions. The pulsating frequency is suggested to be not more than 10π Hz. Finally, the correlation for predicting cycle-averaged Nusselt number of ice slurry in pulsating flow is established, and obtaining the reasonably good prediction results.