Numerical Simulation And Experimental Study Of Coal Slurry Conveying Pump

With energy consumption increase and following petroleum shortage all over the world, much more attention has been paid to the coal liquefaction technology in the process of coal-oil conversion. The performance of coal slurry conveying pump, which is one of the key devices in the coal direct liquefaction technology, has a direct influence on the stability of the whole system. Now most of the researches about the fluent flow in the reciprocating pump focused on the static or steady analysis, however, there were few reports on the dynamic simulation both domestically and abroad.Based on the computational fluid dynamic (CFD) method, dynamic simulation of the flow field in the pump experimental device was conducted with the dynamic mesh model offered by FLUENT. Practical operation and DCS experiment were also carried out to study the whole fluent flow in this paper.Numerical simulation for the whole device in the design condition was conducted and the changing process of flow field for the periodic motion was obtained. The result showed that the initiatory pump could convey coal slurry, but it could not work for a long time due to the blocking and backflow problems. The new numerical simulation and practical operation were studied after shortening piston stroke and increasing crank speed. Though the condition was a little better, the old problems were not alleviated while the stability of the whole system declined because of the high speed.Considering these disadvantages, we changed valve structure and reduced crank speed to increase the system stability. The new research showed that the pump could convey coal slurry continuously and smoothly with raised internal flow speed and alleviated blocking and backflow problems.The experiment research with DCS monitoring outlet flux was also conducted in this paper. It was found that experiment results basically agreed with simulation results.This work may provide reference for the numerical simulation method of dynamic flow and technical foundation for domestic production of coal slurry conveying pump.