Solid-Liquid Flow of Axial Flow Pump in Loop Reactor and Operating Control with Single Invert

Abstract

Solid concentration changes may affect the solid-liquid flow of the axial flow pump in the polypropylene loop reactor, accompanied with unstable operations (e.g., axial power fluctuation). The influencing factors and formation mechanisms of axial power fluctuation were analysed. After that, to discuss the influences of energy allowance of the mixture media in the loop reactor, the internal flow status of the pump under different solid volume fractions were compared. Then a head-correction strategy of operating control with single invert was proposed, to smooth the axial power fluctuation of the axial flow pump. Results demonstrate that viscosity of the mixture media is positively related, whereas the head of the axial flow pump is negatively correlated with solid concentration. Besides, head-correction curves can effectively regulate the off-design operation of pump under different solid volume fractions, with the energy allowance and the axial power fluctuation reduced in the loop reactor and the pump. Researches provide important references for the analysis of internal flow status and the solution of axial power fluctuation of the axial flow pump in the polypropylene loop reactor.

CFD Simulation on Hydrodynamics of Underwater Vehicle with Ducted Propellers

“…The CFD method is effectively used to simulate the situation of deep-sea operation vehicles underwater [21,22]. And it is also widely used to analyse the influence of moving objects on the surrounding flow field [23,24]. In this paper, the CFD method was tested and verified, and a simulation model of the overall underwater vehicle is established.…”