Assessments of the heat transfer performance of a novel continuous oscillatory baffled crystallizer via two-fluid model

Abstract

An Eulerian-Eulerian two-fluid model which incorporates the kinetic theory of granular flow, the energy balance equations, was firstly applied to investigate the heat transfer performance of solid–liquid two-phase flow in continuous oscillatory baffled crystallizers (COBC). The results show that the novel COBC (#6) has both excellent heat transfer and particle suspension performance, as compared with other COBCs, indicating that importance of optimizing the chamber connection structure of COBCs. Then, the COBC #6 was further selected to study the effects of operating conditions and particle physical properties on its heat transfer performance. With increase of oscillation Reynolds number (Reo), the radial mixing of fluid gradually reaches the peak, resulting in the increasing rate of Nusselt number (Nu) gradually decreases. Compared with single-phase flow, the existence of solid particles can produce shear stress on the wall surface, reducing the thickness of heat transfer boundary layer and thermal resistance, thereby increasing the heat flux. With increase of particle size or volume fraction, such effect becomes more obvious, which significantly enhances heat transfer. The novel designed COBC can be operated in the optimized Reo to achieve good heat transfer performance and low power consumption.