基于声比拟法的埋地输气管道泄漏数值模拟

Numerical Simulation of Buried Gas Pipeline Leakage Based on Acoustic Wave Analogy

为研究埋地天然气管道泄漏声源的特性,运用声比拟法(FW-H)与CFD理论对管道泄漏声场进行仿真模拟,计算泄漏声场气动噪声源的类型与声强信号,为检测和定位泄漏点位置奠定理论基础。结果表明:埋地管道发生泄漏后,管内流体速度分布均匀,管外土壤中泄漏流体的速度变化梯度较大;管道泄漏的主要声源是偶极子与四极子声源,其中偶极子声源集中在管道内壁面,四极子声源集中在管道外的开阔区域;随着埋地管道内压的增加与泄漏口直径的扩大,泄漏声场的声波强度逐渐增大,但泄漏口直径变化所引起的声强增幅程度远小于内压变化所引起的声强变化。

In order to study the characteristics of the leakage sound source of buried natural gas pipeline,the sound field of the pipeline leakage is simulated using sound analogy method(FW-H)and CFD theory,and the type and sound intensity signal of the aerodynamic noise source of the leakage sound field are calculated to lay a theoretical foundation for the detection and location of the leakage point.The results show that after the buried pipeline leaks,the fluid velocity distribution in the pipeline is uniform,and the velocity change gradient of leaking fluid in the soil outside the pipeline is large.The main sound sources of pipeline leakage are dipole and quadrupole sound sources,among which the dipole sound source is concentrated on the inner wall of the pipeline,and the quadrupole sound source is concentrated in the wide area outside the pipeline.With the increase of the internal pressure and leakage port diameter of the buried pipeline,the sound wave intensity of the leakage sound field gradually increases.However,the change of sound intensity caused by the change of leakage port diameter is far less than that caused by the change of internal pressure.