Improvement of separation efficiency and production capacity of a hydrocyclone

The improvement of separation efficiency (SE) and production capacity of a hydrocyclone by introducing a newly-designed structure is a significant challenge when applying Reynolds Averaged Navier–Stokes (RANS) turbulence modeling techniques. This study aims to solve the problem that the high content of fine sands in summer in the Chongqing section of the Yangtze River means that it can not be directly taken as the water source for a heat pump system, and also to reduce the energy consumption of the hydrocyclone through the improvement of its structure design. In this research, the RANS approach was applied to simulate the three-dimensional flow field of the hydrocyclone, a Reynolds stress model (RSM) was introduced and used to make the RANS equation close. In the modeling study of the separation mechanism of the hydrocyclone, the impacts of operating parameters and structure parameters on the hydrocyclone SE were studied using RANS methods based on the commercial software FLUENT. Consequently, a new-style hydrocyclone with inclined inlet and ramp board and central solid rod was designed to enhance the SE according to previous numerical modeling results. Under the conditions of the optimal inlet velocity of 15 m s⁻¹ for the new structure and with a sand volume fraction of 10%, the SE of the new structure can be increased near to 60% for 0.004 mm sand particles, and the overflow production capacity can be enhanced to 20 m³ h⁻¹. These data are required both for evaluating the potential use of the hydrocyclone for the separation of sands from water and for studying the new structure which may be important in practical applications to reduce energy consumption, and these comparisons will assist hydrocyclone designers in choosing appropriate turbulence models and structures, and benefit future modeling research.