高压管道泄漏的CFD仿真分析与试验研究

发布时间：2018-06-05 10:07

本文选题：高压管道 + 泄漏　；参考：《华北电力大学(北京)》2017年硕士论文

【摘要】：管道在输送过程中出现破裂或穿孔等现象,严重威胁到管道输送的安全性。为了研究高压管道微泄漏的在线检测技术,及时准确地检测出高压输气管道的微小泄漏故障,避免恶性泄漏事故的发生,对管道泄漏理论进行研究,推导出管道泄漏量计算公式。通过试验对公式进行验证,结果表明管道泄漏量的理论计算公式对于管道泄漏量的计算具有一定参考价值。采用计算流体力学(Computational Fluid Dynamics,CFD)方法对高压管道泄漏进行了流场仿真计算与分析。对不同泄漏孔径、不同管道内部压力下高压管道泄漏的流场进行了仿真计算分析,并应用质量流量理论公式和管道泄漏试验对CFD仿真结果进行了验证。仿真结果表明,高压管道发生泄漏时泄漏孔内存在明显的湍流扰动现象;当泄漏孔径相同时,泄漏孔内外压差越大,泄漏孔内的流场变化越剧烈,湍流扰动现象越明显;当管道内外压差相同时,泄漏孔径越大,泄漏孔内的流场变化越剧烈,湍流扰动现象越明显。在CFD流场仿真的同时开启气动噪声模型Ffowcs Williams和Hawkings方程进行声场仿真。通过计算对管道泄漏的声源发射面进行确定,并对管道泄漏超声波的方向性进行研究,对不同管内压力下的声场进行仿真分析。结果表明,管道发生泄漏时产生的气动噪声是一种宽频噪声;离泄漏孔越远,超声波声压越小;声压信号接受点的所处的角度越大,该点所接收到的声压信号越小;管道泄漏孔径相同的情况下随着管道内压力增加,声音接收点声压信号随之增大。因此,通过对管道内部湍流扰动产生的超声波进行测量,可以检测出高压输气管道的泄漏故障。
[Abstract]:The safety of pipeline transportation is seriously threatened by such phenomena as rupture or perforation in the course of pipeline transportation. In order to study the on-line detection technology of micro leakage in high pressure pipeline, detect the micro leakage fault of high pressure gas pipeline in time and accurately, and avoid the occurrence of malignant leakage accident, the theory of pipeline leakage is studied. The calculation formula of pipeline leakage is derived. The experimental results show that the theoretical calculation formula of pipeline leakage has some reference value for the calculation of pipeline leakage. Computational fluid dynamics (CFD) method is used to simulate and analyze the flow field of high pressure pipeline leakage. The flow field of high pressure pipeline with different leakage aperture and internal pressure is simulated and analyzed, and the CFD simulation results are verified by mass flow theory formula and pipeline leakage test. The simulation results show that there is obvious turbulence disturbance in the leak hole when the leakage occurs in high pressure pipeline, and when the leakage aperture is the same, the greater the pressure difference between the leak hole and the outside hole, the more intense the flow field in the leak hole is, and the more obvious the turbulence disturbance phenomenon is. When the pressure difference inside and outside the pipeline is the same, the larger the leak aperture is, the more intense the flow field in the leak hole is and the more obvious the turbulence disturbance is. The aerodynamic noise model Ffowcs Williams and Hawkings equation are opened simultaneously to simulate the CFD flow field. The acoustic emission surface of pipeline leakage is determined by calculation, and the directivity of ultrasonic wave is studied, and the sound field under different pressure in pipe is simulated and analyzed. The results show that the aerodynamic noise produced by pipeline leakage is a kind of wide-band noise, the ultrasonic sound pressure is smaller as far away from the leak hole, the greater the angle of the receiving point of the sound pressure signal, the smaller the sound pressure signal received at that point. Under the same leakage aperture, the sound pressure signal at the receiving point increases with the increase of the pressure in the pipeline. Therefore, the leakage fault of high pressure gas transmission pipeline can be detected by measuring the ultrasonic wave generated by the turbulence disturbance in the pipeline.
【学位授予单位】：华北电力大学(北京)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U171

【参考文献】