气固两相流固相浓度与流速的测量及可视化

Measurement and visualization of concentration and velocity of solid phase in the gas-solid two-phase flow

气固两相流固相流率的测量是测试领域的难点之一,为了实现气固两相流固相浓度与流速的测量,阐述了电容层析成像的原理,搭建了气固两相流实验台,固相选用聚丙烯颗粒,气相为空气,固相依靠自身的重力流经实验装置,利用ITS公司的M3C电容层析成像装置对气固两相流的固相浓度、速度、质量流量进行了测试研究。实验中的浓度测量采用图像的介电常数分布像素,速度测量选择双层结构的电容传感器,利用相关测速原理,计算上下游传感器成像像素的相关性,最后由测得的速度及浓度分布计算出质量流量,测量结果与重力传感器测量的质量流量结果进行了对比,结果具有较好的一致性,测量误差小于10%,表明利用电容层析成像系统可对气固两相流参数的测量。

Measurement of the solid phase flow rate in the gas-solid two-phase flow is one of the difficulties in test realm.In order to realize visualization measurement of gas-solid two phase flow,the principle of electrical capacitance tomography was stated and a gas-solid two phase flow test-bed was developed.Polypropylene particles and air were selected as the solid phase and gas phase.Solid phase relied on their own gravity flow through experimental device.M3C capacitance tomography device of ITS company was used for the test and research on solid phase concentration,speed and mass flow rate in the gas-solid two phase flow.In the experiment,concentration measurement was based on the dielectric constant distribution of the pixels about image.Capacitive sensor with double layer structure was used to measure velocity.The relevant principles of the speed measurement was used to compute the correlation between upstream and downstream of sensor imaging pixel.Finally,the mass flow was calculated by the measured velocity and concentration distributions.The mass flow measurements were compared with the results of gravity sensor.The results showed good agreement with measurement error of less than 10%.The experimental results indicated that the capacitance tomography system can be used to measure the parameters of gas-solid two phase flow.