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基于低压大流量自激振荡射流形成及自激振荡脉冲气体的运动规律,提出了固-脉冲波峰点接触的“滚动摩擦”自激振荡脉冲式天然气管道输送运动形式。分析了下游喷嘴直径、腔室直径、腔室长度和腔室碰撞壁倾角等结构参数对天然气管道减阻增输特性的影响,并确定了较优的自激振荡脉冲腔室无量纲参数。研究结果表明:腔室下喷嘴直径反映自激振荡脉冲射流的过流特性,腔室直径影响自激振荡脉冲射流涡旋配对效果,腔室长度与自激振荡脉冲射流振荡频率及脉动幅值有关,碰撞壁倾斜角直接决定腔室涡漩中心的位置,进而产生周期性高压脉冲射流团的特殊聚能效应。计算后获得的自激振荡脉冲腔室较优无量纲参数为:腔室下游喷嘴与上喷嘴直径比为1.3,腔室长度与上喷嘴直径比为2.4,腔室直径与上喷嘴直径比为6,腔室碰撞壁倾斜角度为120°。
Based on the formation of low-pressure and high-flux self-oscillating jets and the motion of self-excited oscillating pulse gas, a “rolling friction” self-oscillating pulsed natural gas pipeline transportation form of solid-pulse peak contact is proposed. The effects of downstream nozzle diameter, chamber diameter, chamber length and chamber wall inclination on the drag reduction and transmission characteristics of natural gas pipeline were analyzed. And the dimensionless parameters of self - oscillating pulse chamber were determined. The results show that the diameter of the nozzle under the chamber reflects the overcurrent characteristic of the self-excited oscillating pulse jet. The diameter of the chamber affects the matching effect of the self-oscillating pulse jet. The length of the chamber is related to the oscillating frequency and pulse amplitude , The collision wall tilt angle directly determines the vortex center of the chamber, and then generates a special high-pressure pulsed jet clustering effect. The calculated self-oscillating pulse chamber has the following optimal dimensionless parameters: the ratio of the downstream nozzle to the upper nozzle is 1.3, the length of the chamber to the upper nozzle is 2.4, the diameter of the chamber to the upper nozzle is 6 , Chamber collision wall tilt angle of 120 °.