Numerical simulation and structure optimization of coal-liquefying reactor

摘要

A gas-liquid two-phase simulation is carried out with CFD software FLUENT for the purpose of resolving the recycle cup clogging and inefficiency of gas-liquid separation in coal-liquefying reactor,. The effect of slope angle of the recycle cup and size of upper outlet pipe on flow field is investigated. It is indicated that liquid rising velocity increases with the slope angle of the recycle cup, and the turbulence decreases, which relieves the recycle cup clogging. Lager diameter of the upper outlet pipe can reduce the gas content in lower outlet within certain range, but too large size may be harmful for separation due to the decrease of gas content in upper outlet. Decrease in length of the upper outlet pipe dropping into the recycle cup raises the volume fraction of the liquid in lower outlet, thus the efficiency of gas-liquid separation is improved. The study is hoped to have a direct reference value for the optimal design of the coal-liquefying reactor.