电站锅炉炉管泄漏数值模拟及定位算法研究

Numerical Simulation on Boiler Tube Leakage Detection and Study on the Location Algorithm

针对电站锅炉炉管泄漏点精确定位问题,对泄漏喷流形成的流场和声场进行了数值模拟.将通信工程中的Chan算法引入到炉管泄漏定位检测中,分别在空旷环境、实验室环境、模拟炉膛常温无噪声环境和模拟炉膛常温高噪声环境下进行了实验研究.结果表明:泄漏喷流流场轴向速度是引起泄漏声波传播扰动的主要原因,远场的噪声辐射具有指向性特征;在孔口部区域声功率级最大,且声功率级沿对称轴方向随与喷口距离的增大而逐渐扩散衰减,泄漏声场的强度随孔直径的增大而增强;相同孔直径、不同泄漏蒸汽工况下的声功率级基本相同;通过Chan算法对泄漏进行定位,定位结果误差在工程允许误差范围内,定位精度较高.

To accurately locating the boiler tube leakage point,numerical simulation was conducted on the flow field and sound field formed by the leakage jet flow.The Chan algorithm in communication engineering was introduced to the location detection of boiler tube leakage,and test studies were made respectively under open environment,laboratory environment,simulated cool furnace noise-free environment and simulated cool furnace high-noise environment.Results show that the axial velocity of leakage jet flow is the main reason of leakage sound propagation and disturbance,and the noise radiation has directive property in the far field.The sound power level of leakage flow near jet exit is the highest,which decreases with the rise of distance to the jet exit along symmetrical axis.The intensity of sound field increases with rising pore diameter of leakage flow.The sound power level is basically the same under same pore diameter but different steam conditions.The location error of Chan algorithm is within the allowable range,indicating high resolution of the algorithm.