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本文介绍国内外近年来采用各种类型的强化传热管,提高列管式换热器的传热效率,减少传热面积及流体阻力,降低设备及操作费用,充分回收工厂余热,特是低品位能源的情况.强化传热分无相变的传热强化与有相变的传热强化两种,在无相变的传热强化中,对管内流体而言,可以采用螺旋槽纹管、横槽纹管、缩纹管、内翅片管、管内加插入物(如麻花片、螺旋线)、流体中加固体颗粒,或使流体产生脉动等方法来强化传热;对有相变的传热强化,用于强化有机物(如烷烃、烯烃类,氟里昂类)的冷凝可采用单面纵槽管、低螺纹翅片管、锯齿形翅片管及径向辐射状翅片管等;用于强化沸腾或蒸发的管子有表面多孔管(介绍了烧结法与机械加工法两种)及双面纵槽管等.本文对几种效果较好的强化传热管,分别介绍了其结构、原理、性能、应用范围及计算公式等,作为选择强化传热方法的参考.
In this paper, we introduce various types of heat transfer tubes at home and abroad in recent years to improve heat transfer efficiency of tube heat exchangers, reduce heat transfer area and fluid resistance, reduce equipment and operating costs, and fully recover factory waste heat, especially low Grade energy situation.High heat transfer points without phase transition heat transfer enhancement and phase transition heat transfer enhancement in heat transfer enhancement without phase transition, the tube of fluid, the spiral groove can be used, Horizontal grooved tube, retractable tube, inner finned tube, tube inserted insert (such as twist, spiral), the fluid in the solid particles, or make the fluid pulse and other methods to enhance heat transfer; for the phase change Heat transfer enhancement, for strengthening the condensation of organic matter (such as alkanes, alkenes, Freons) can be used single-sided longitudinal slot tube, low-threaded finned tube, serrated finned tube and radial radial finned tube; The tubes used to enhance the boiling or evaporation have surface porous tubes (introduced two kinds of sintering method and mechanical processing method) and double-sided longitudinal groove tube, etc. In this paper, several structures of heat transfer tubes with better effect are introduced respectively , Principle, performance, application range and calculation formula, as the choice of strengthening pass Reference method.