首页> 外文期刊>International Journal of Heat and Mass Transfer >Downward two phase flow experiment and general flow regime transition criteria for various pipe sizes
【24h】

Downward two phase flow experiment and general flow regime transition criteria for various pipe sizes

机译:不同管径的向下两相流实验和一般流态转换标准

获取原文
获取原文并翻译 | 示例
           

摘要

Flow regime map is often used in choosing constitutive correlations for the two-phase flow model. The related research mainly concentrates on the vertical upward and horizontal flow, while it is not sufficient in the vertical downward flow. Downward flow is very important as it is frequently encountered in the industrial applications. To enrich the downward flow research, an experiment is performed on a piping system with an inner diameter of 0.1524 m. Four different flow patterns (bubbly flow, cap bubbly flow, churn turbulent flow, and annular flow) are classified with the artificial neural network method. The probability density function (PDF) profile of each flow pattern is discussed. The proposed flow regime map is compared with the other experiments and the effect of the pipe size is discussed. The existing downward flow regime boundary criteria are assessed with the experiment results. It is found that these criteria cannot fit the experiment results well. A set of general boundary criteria are still needed. In this paper, the criteria for the boundary of the bubbly flow, the boundary between the cap bubbly flow and the slug flow, and the boundary of the falling film regime are proposed. They are verified with the experiments on different size pipes. A significant inlet effect on the flow regime boundary is found. The falling film boundary criterion proposed cannot be applied when a sparger is used to inject gas into the downward test section.
机译:流态图通常用于选择两相流模型的本构关系。相关研究主要集中在垂直向上和水平方向的流动,而在垂直向下方向的流动还不够。向下流动非常重要,因为在工业应用中经常会遇到这种情况。为了丰富向下流动的研究,对内径为0.1524 m的管道系统进行了实验。用人工神经网络方法将四种不同的流型(气泡流,瓶盖气泡流,搅动湍流和环形流)分类。讨论了每种流型的概率密度函数(PDF)曲线。将拟议的流态图与其他实验进行比较,并讨论了管道尺寸的影响。实验结果评估了现有的向下流态边界标准。发现这些标准不能很好地符合实验结果。仍然需要一组通用边界条件。在本文中,提出了气泡流的边界,帽状气泡流和团状流之间的边界以及降膜状态的边界的判据。通过不同尺寸管道上的实验对它们进行了验证。发现在流态边界上有明显的入口效应。当使用喷射器将气体注入向下的测试区域时,建议的降膜边界标准无法应用。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号