The local gas-phase flow characteristics such as local gas holdup(εg), local bubble velocity (V_b) and local bubble mean diameter(d_b) at a specified point in a gas-liquid-solid three-phase reversedflow jet loop reac...The local gas-phase flow characteristics such as local gas holdup(εg), local bubble velocity (V_b) and local bubble mean diameter(d_b) at a specified point in a gas-liquid-solid three-phase reversedflow jet loop reactor was experimentally investigated by a five-pointconductivity probe. The effects of gas jet flow rate, liquid jet flowrate, solid loading, nozzle diameter and axial position on the localεg, V_b and d_b profiles were discussed. The presence of solids atlow solid concentrations not only increased the local εg and V_b,but also decreased the local d_b. The optimum solid loading for themaximum local εg and V_b together with the minimum local d_b was0.16×10^-3 m^3, corresponding to a solid volume fraction ε_S＝2.5/100.展开更多
The local liquid--phase characteristics of the gas--liquid two-phase and gas--liquid--solid threephase self-aspirated reversed flow jet loop reactor with a concentric gas--liquid injection nozzle were studied experime...The local liquid--phase characteristics of the gas--liquid two-phase and gas--liquid--solid threephase self-aspirated reversed flow jet loop reactor with a concentric gas--liquid injection nozzle were studied experimentally. They facilitate the evaluation of local phenomena. The local instantaneous liquid velocities at different axial positions of the reactor were measured by using the modified pilot tube.The local liquid-phase turbulent structural parameters such as time-averaged velocity. turbulent nuctuating velocity and turbulent micro scale were calculated with the aid of the statistical theory of turbulence. In particular, effects of liquid jet flowrates and solid loadings on the profiles of the liquid--phase turbulent structural parameter both in the jet effective region and in the tubular region inside the draft tube were discussed.展开更多
基金Supported by the National Natural Science Foundation of China (No. 29706006) and the General Corporation of Petrochemical Engineering of China (No.X598021).
文摘The local gas-phase flow characteristics such as local gas holdup(εg), local bubble velocity (V_b) and local bubble mean diameter(d_b) at a specified point in a gas-liquid-solid three-phase reversedflow jet loop reactor was experimentally investigated by a five-pointconductivity probe. The effects of gas jet flow rate, liquid jet flowrate, solid loading, nozzle diameter and axial position on the localεg, V_b and d_b profiles were discussed. The presence of solids atlow solid concentrations not only increased the local εg and V_b,but also decreased the local d_b. The optimum solid loading for themaximum local εg and V_b together with the minimum local d_b was0.16×10^-3 m^3, corresponding to a solid volume fraction ε_S＝2.5/100.
文摘The local liquid--phase characteristics of the gas--liquid two-phase and gas--liquid--solid threephase self-aspirated reversed flow jet loop reactor with a concentric gas--liquid injection nozzle were studied experimentally. They facilitate the evaluation of local phenomena. The local instantaneous liquid velocities at different axial positions of the reactor were measured by using the modified pilot tube.The local liquid-phase turbulent structural parameters such as time-averaged velocity. turbulent nuctuating velocity and turbulent micro scale were calculated with the aid of the statistical theory of turbulence. In particular, effects of liquid jet flowrates and solid loadings on the profiles of the liquid--phase turbulent structural parameter both in the jet effective region and in the tubular region inside the draft tube were discussed.
