不同规格节流孔板的节流和声学特性

Throttling and Acoustic Characteristics of Throttling Orificeplate with Different Configurations

为探究节流孔板开孔形状及结构对管道压降效果及振动辐射噪声的影响,在消声室内对开孔面积相同的圆形和方形节流孔板、开孔面积不同的圆形节流孔板、圆形台阶状节流孔板进行了振动及声压级测试,并通过仿真模拟分析了不同节流孔板性能差异的内在机理.结果表明:方形节流管道的流体在运行过程中的机械能损失最大,与同样开孔面积的圆形节流管道的压降最大相差12.6 kPa,且该管道测点在全频域范围内的应变幅值和声压级均明显高于其他3种管道;台阶形节流孔板使管内流体局部最小压力有效提升,减少汽蚀的产生,故该管道辐射声压级最小.

In order to explore the effect of hole shape and the structure of the throtting orificeplate on the pressure drop of pipelines and the noise generated by the vibration of the pipeline,the vibration and sound pressure level of four different throtting orificeplate in an anechoic chamber were studied.The mechanism of throtting orificeplate with different configurations were analyzed by numerical simulation.The results show that the mechanical energy loss of flow in throttle pipe with square hole shape is the largest,whose pressure drop is 12.6 kPa bigger than that in the pipe with circular hole shape and the same opening.The stress amplitude and the sound pressure level of that pipe are both obviously higher than that of other three pipes.The throttling orificeplate with stepped hole can effectively raises the local minimum pressure of the fluid in the pipe and reduces the occurrence of cavitation,so the radiated sound pressure level of the pipe is the smallest.