ABSTRACT

The present research work aims at providing data on heat transfer by forced convection from three-dimensional bodies suspended in a free stream of air. The shapes investigated covered cubic and rectangular bodies with air flow parallel and normal to the body’s axis. The experiments were carried out inside an air duct in which air flows over a model for the three-dimensional body. The results obtained were represented by power function relations between the Nusselt and Reynolds number. The results were divided into the main body axis was parallel to the direction of the air flow. The heat transfer from the whole cube could be broken to the face components. This showed that the sides and rear face were responsible for more heat transfer. Increasing the length of the rectangular body increased the heat transfer. The equation representing the increase of heat transfer with length is suggested. The present results are essential in designing air-conditioned railway coaches, heated liquid wagons, refrigerated cars, and food and fluid carriers.

摘要

目前的研究工作旨在提供悬浮在自由空气流中的三维物体强制对流传热的数据。所研究的形状覆盖立方体和矩形体，气流平行于和垂直于体的轴线。实验是在空气管道内进行的，空气在三维身体模型上流动。获得的结果用努塞尔数和雷诺数之间的幂函数关系来表示。结果分为主体轴线与气流方向平行。从整个立方体到表面组件的热传递可能会被破坏。这表明侧面和背面负责更多的热传递。增加矩形体的长度增加了传热。提出了表示传热随长度增加的方程。目前的结果对于设计空调铁路客车、加热液体货车、冷藏车以及食品和液体运输车至关重要。