矿用静电感应式粉尘浓度传感器的优化研究

Optimization Study on Electrostatic Induction Dust Concentration Sensor for Mine

针对目前静电感应式粉尘浓度传感器在低浓度时测量不精确的问题,利用卡门涡街与文丘里效应相结合的方法改进传感器的测量管道,提出在文丘里管道的喉道段加入一个三角柱,在两种流体力学效应的相互作用下,增加粉尘颗粒运动速度和改变运动轨迹,进而提高感应电荷量。利用CFD软件,在Gambit 2.4中建立改进的试验模型,Fluent 6.3中设置气固两相流的试验参数进行仿真试验,得到粉尘颗粒的速度分布云图和运动轨迹图,利用环形静电传感器的感应电荷计算式,在MATLAB中计算不同粒径下的感应电荷量。结果表明:对比项目组研究的文丘里管道,改进的管道结构使感应电荷量整体提高约20%,粒径10μm以下提高约30%,从而提高了低浓度条件下粉尘浓度的测量精度。

In view of the inaccurate measurement of electrostatic induction dust concentration sensor under the condition of low concentration at present,the method of combining Carmen vortex street and Venturi effect was used to improve the measurement pipeline of existing dust concentration sensor.It was proposed to add a triangular column to the throat section of Venturi pipeline.Through increasing the movement speed and changing the movement track of dust particles under the interaction of two kinds of hydrodynamics phenomena,the amount of induced charge can be improved.Using CFD software,an improved experimental model was established in Gambit 2.4.In Fluent 6.3,the experimental parameters of gas-solid two-phase flow were set up for experimental simulation.The velocity distribution nephogram and motion trace diagram of dust particles were obtained.Using the induced charge calculation formula of the ring electrostatic sensor,the amount of induced charge under different particle sizes was calculated in MATLAB.The results show that compared with the previous Venturi pipe studied in the project team,the improved pipe structure can increase the total amount of induced charge by about 20%,and the dust particle size under 10μm increases by about 30%,so that the measurement accuracy of dust concentration under low concentration conditions can be improved.