PYI Award: Studies of Convective Boiling in Compact Heat Exchanger Geometrics and Mixed Convection Heat Transfer

本研究包括两个方面的研究，第一个领域是对流沸腾和紧凑型换热器内的两相流动。通过一系列的实验和分析研究了流动条件、流体性质和几何形状对带有偏置条形翅片的通道内的对流沸腾换热的影响。计划进行流动可视化研究和局部换热系数的直接测量。文中还研究了肋板和凹陷管内的对流沸腾。该项目的第二部分包括在水平强迫流动存在的情况下，矩形封闭空间内加热垂直壁面附近的混合对流的实验和理论研究。对于不同的外壳几何形状，实验检验了强迫流动和浮力机制之间的相互作用，并确定了它们对流动和换热的综合影响。同时进行了流场和换热的数值模拟，并与实验结果进行了比较。

The research consists of studies in two areas, the first being convective boiling and two-phase flow in compact heat exchangers. A series of experimental and analytical studies is employed to investigate the effect of flow conditions, fluid properties, and geometry on convective boiling heat transfer in channels with offset strip fins. Flow visualization studies and direct measurements of local heat transfer coefficients are planned. Convective boiling in ribbed-plate and dimpled-tube geometries is also examined. The second portion of the project consists of experimental and theoretical studies of mixed convection flows near the heated vertical walls of a rectangular enclosure in the presence of a horizontal forced flow. For different enclosure geometries, the experiments examine the interaction between the forced-flow and buoyance mechanisms, and determine their combined effects on flow and heat transfer. Numerical predictions of the flow field and heat transfer are developed concurrently and compared with the experimental results.