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管内湍流强化传热方法一般是增加壁面换热面积,但这会显著提高管内流动阻力。本文根据管内核心流强化传热的原理,提出了一种高效低阻的叶片旋流管,分析其传热强化的机理,建立相应的物理和数学模型。数值分析的结果表明,在圆管内置若干组旋流叶片后,可显著强化管内湍流换热,且流动阻力的增幅低于换热强化的增幅;当常温水流过管长为960mm,管径为20mm的圆管,且在管内核心流区域设置4组4叶片旋流单元时,其性能评价系数SPEC在Re数为3000～15000的范围内均超过1.5,最高可达1.9左右。
Tube turbulence enhancement heat transfer method is generally to increase the wall heat transfer area, but it will significantly increase the flow resistance within the tube. In this paper, based on the principle of enhanced heat transfer in the core of the tube, a highly efficient and low resistance vane swirl tube is proposed. The mechanism of heat transfer enhancement is analyzed and the corresponding physical and mathematical models are established. The results of numerical analysis show that the turbulent heat transfer in the tube can be significantly enhanced after the tube is equipped with a number of swirl vanes, and the increase of the flow resistance is lower than that of the heat transfer enhancement. When the water flow at a normal temperature is 960mm and the tube diameter is 20mm round tube, and when 4 sets of 4-blade swirl units are arranged in the core flow area in the tube, the performance evaluation coefficient SPEC exceeds 1.5 and reaches a maximum of about 1.9 in the Re number of 3000 to 15000.