概述了转子组合式强化传热装置的强化传热和自清洁原理,通过实验研究了内置螺旋叶片转子及叶片间断型转子换热管的传热和阻力特性。实验结果表明,在相同的Re条件下,内置螺旋叶片转子换热管管内的Nusselt数高于内置叶片间断型转子换热管,阻力系数低于内置叶片间断型转子换热管,同时PEC值明显高于叶片间断型转子的PEC值,说明内置螺旋叶片转子换热管的综合性能优于叶片间断型转子。
Enhanced heat transfer technology is an energy-saving technology.For new types of tube inserts,the mechanism of the rotors-assembled device for heat transfer enhancement and automatic cleaning is introduced in this paper.Experiments were carried out in order to study the heat transfer and friction characteristics of the tube inserted with helical blade rotors and discrete blade rotors.An experiment with a smooth tube was used to calibrate the experimental system and data reduction method.The experimental results show that the Nusselt number from the tube inserted with rotors is higher than that of plain tube within the experimental range of Reynolds number,though the friction factor of the tube with rotors inserted is slightly higher.The comparison of the tubes inserted with helical blade rotors and discrete blade rotors shows that the former present higher Nusselt number,lower friction factor and higher PEC value,indicating that the comprehensive performance of helical blade rotor is better.