模拟贯穿裂纹内高速气液两相流动特性研究

Study on the characteristics of high-speed gas-liquid two phase flow in a simulated crack

中文关键词: 泄漏  气-液两相流  安全  狭缝通道  多相流

英文关键词: leakage  gas-liquid flow  safety  slit  multiphase flow

中文摘要:

      压力管道和容器发生贯穿泄漏会引发严重的事故,合理估算贯穿泄漏量具有重要的工程意义。本文以矩形狭缝通道模拟贯穿裂纹,开展了高压氩气-水贯穿模拟裂纹的高速流动可视化试验研究,狭缝长度为20mm,间隙宽度为0.08-0.18mm。试验进口压力大于5000kPa,液体的表观速度区间为0.05-58.62m/s,气体表观速度区间为1.71-34.27m/s,采用两侧进水中间进气的特殊入口方式,研究了非均匀混合流体通过狭缝通道的流动特性。研究表明：入口压力越大出口位置压降的加速效应越明显；气体在并行双入口下,流体入口存在明显不对称流动现象,狭缝内高速气液流两相滑速比差异较小；依据本文的试验数据对两相摩擦压降的计算模型进行了验证和评价,采用Sun-Mishima关系式时对泄漏流量的估算效果最好,均相模型也具有较好的计算精度；当狭缝宽度为0.08mm时,现有关系式估算泄漏量偏小。

英文摘要:

      The penetrating leakage of pressure pipes and vessels can cause serious accidents, and the estimation of penetrating leakage has important engineering significance.. In this paper, a visualized experimental study on simulated crack leakage through a rectangular slit channel was carried out. The length of the slit is 20mm and the width is 0.08-0.18 mm. The experimental inlet pressure is as high as 5000 kPa, the apparent velocity range of liquid is 0.05-58.62m/s, and the apparent velocity range of gas is 1.71-34.27m/s. The flow characteristics of non-uniform mixed fluid through a narrow channel were studied by using a special inlet mode of water inlet on both sides and air inlet in the middle. The main conclusions are as follows: The larger the inlet pressure is , the more obvious the acceleration effect of the pressure drop at the outlet is; Under the condition of parallel double inlets, the asymmetric flow appears at the fluid inlet; Based on the experimental data in this paper, the two-phase friction pressure drop prediction model was verified and evaluated. The Sun-Mishima relationship is the most accurate estimation of the leakage flow, and the homogeneous model also has better calculation accuracy. When the slit width is 0.08mm, the leakage flow estimated by the existing relationship is too small.