The feasibility of applying Capacitively Coupled Contactless Conductivity Detection （C4D） technique to measurement of bubble velocity in gas-liquid two-phase flow in millimeter-scale pipe is investigated. And, a new...The feasibility of applying Capacitively Coupled Contactless Conductivity Detection （C4D） technique to measurement of bubble velocity in gas-liquid two-phase flow in millimeter-scale pipe is investigated. And, a new method, which combines the C4D technique and the principle of cross-correlation velocity measurement, is proposed for the measurement of bubble velocity. This research includes two parts. First, based on the principle of C4 D, a new five-electrode C4D sensor is developed. Then, with two conductivity signals obtained by the C4D sensor, the velocity measurement of bubble is implemented according to the principle of cross-correlation. The research results indicate that the C4D technique is highly effective and anticipates a broad potential in the field of two-phase flow. Experimental results show that the five-electrode C4D sensor is suitable for measuring the velocity of single bubbles with a relative error of less than 5%.展开更多
A new model for determining bubble size distributions in bubble columns by the dynamic gasdisengagement(DGD)technique is developed.It is based on an idea of non-uniform steady statedirstribution of bubble dispersion.I...A new model for determining bubble size distributions in bubble columns by the dynamic gasdisengagement(DGD)technique is developed.It is based on an idea of non-uniform steady statedirstribution of bubble dispersion.Interpreting the axial non-uniformity,this model gives axial gasholdup distributions.If assuming an axially homogeneous dispersion,a radial gas holdup distributioncan be obtained.The Sauter mean diameters or specific interfacial areas for several systems areestimated by the technique.The results for an air-water system agree with those measured by afive-point conductivity probe technique.The obtained axial gas holdup distributions agree well withreported measurements and the radial gas holdup distributions are also reasonable.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51076141 and 60972138)
文摘The feasibility of applying Capacitively Coupled Contactless Conductivity Detection （C4D） technique to measurement of bubble velocity in gas-liquid two-phase flow in millimeter-scale pipe is investigated. And, a new method, which combines the C4D technique and the principle of cross-correlation velocity measurement, is proposed for the measurement of bubble velocity. This research includes two parts. First, based on the principle of C4 D, a new five-electrode C4D sensor is developed. Then, with two conductivity signals obtained by the C4D sensor, the velocity measurement of bubble is implemented according to the principle of cross-correlation. The research results indicate that the C4D technique is highly effective and anticipates a broad potential in the field of two-phase flow. Experimental results show that the five-electrode C4D sensor is suitable for measuring the velocity of single bubbles with a relative error of less than 5%.
文摘A new model for determining bubble size distributions in bubble columns by the dynamic gasdisengagement(DGD)technique is developed.It is based on an idea of non-uniform steady statedirstribution of bubble dispersion.Interpreting the axial non-uniformity,this model gives axial gasholdup distributions.If assuming an axially homogeneous dispersion,a radial gas holdup distributioncan be obtained.The Sauter mean diameters or specific interfacial areas for several systems areestimated by the technique.The results for an air-water system agree with those measured by afive-point conductivity probe technique.The obtained axial gas holdup distributions agree well withreported measurements and the radial gas holdup distributions are also reasonable.
