垂直内螺纹管内超临界水的二次流特性

发布时间：2018-04-25 09:09

本文选题：计算流体力学 + 内螺纹管　；参考：《热科学与技术》2016年02期

【摘要】：运用计算流体力学方法,采用SSG雷诺应力模型对高温条件下垂直内螺纹管中超临界水的二次流特性进行了研究。研究发现:内螺纹的导流作用在垂直于主流的方向产生了很强的二次流场,主流焓的变化对二次流场的基本结构影响很小。内螺纹管周向和径向上的传热系数分布不均,超临界水在螺纹顶部区域的传热效果远好于螺纹底部。在螺纹顶部表面形成的单个旋涡产生一个压力相对较低的区域,传热增强。在大比热区,由于流体热物性急剧变化,传热的不均性更加显著。螺纹底部壁面是内螺纹管周向传热的薄弱位置,其内部结构的优化应重点集中在该区域。
[Abstract]:The secondary flow characteristics of supercritical water in vertical inner threaded pipe under high temperature were studied by using computational fluid dynamics (CFD) and SSG Reynolds stress model. It is found that the flow conduction of internal thread produces a strong secondary flow field perpendicular to the main stream, and the change of the main stream enthalpy has little effect on the basic structure of the secondary flow field. The heat transfer coefficient in the circumferential and radial direction of the inner threaded tube is uneven, and the heat transfer effect of the supercritical water in the top part of the thread is much better than that in the bottom of the thread. A single vortex formed on the top surface of the thread produces a relatively low pressure area, resulting in increased heat transfer. In the large specific heat region, the uneven heat transfer is more obvious due to the rapid change of the fluid thermal physical properties. The bottom wall of the thread is the weak position of the circumferential heat transfer of the inner threaded tube, and the optimization of its internal structure should focus on this area.
【作者单位】：华北水利水电大学热能工程研究中心;大连理工大学能源与动力学院;
【基金】：国家自然科学基金资助项目(51406026) 河南省高校创新团队支持计划资助项目(16IRTSTHN017)
【分类号】：TK124

【参考文献】