稠密气固两相流凸台绕流的声发射测试

Dense Gas-solid Two-phase Flow Around Convex of Acoustic Emission Testing

近几年循环流化床锅炉水冷壁磨损较为严重,虽然采用防磨凸台可以有效减缓壁面磨损,然而基于凸台优化设计的文献还鲜见报道,因此文中使用声发射设备研究凸台绕流过程中稠密气固两相流颗粒与壁面接触程度问题,在一冷态实验台密相区,采用声发射对相同尺寸不同截面形状凸台下方颗粒与壁面接触程度进行测量,并用小波包分解处理信号。实验结果表明,0~10.5 k Hz低频段信号可以反应颗粒与壁面接触程度,重点分析该特征频段能量百分比,提出方形凸台为理论优化凸台,对进一步改进循环流化床防磨技术提供指导意见。

The water wall wear of circulating fluidized bed is particularly serious in last few years. Although anti-abrasionconvex platform can reduce wear effectively, there-s few reports based on convex optimization design on literature before. There-fore, the paper used acoustic emission equipment in researching the contact process between gas-solid two phase flow with theconvex wall. Measuring the acoustic emission on contact degree on the bottom side of gas-solid two phase flow and the convex wallunder in same size different cross section shape, wavelet packet was used in signal processing decomposition. The result showsthat the contract degree can be reflected under low frequency signal on 0～ 10.5 kHz.The paper puts forward a square shaped con-vex platform. It is given out by analyzing the energy percentage of the spectrum. This will provide guiding ideology in improvingthe circulating fluidized bed wear technology.