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通过内插螺旋方法使换热器换热管内流体产生螺旋流,实验研究了管内螺旋流/螺旋流态化的颗粒直径、颗粒浓度、螺旋结构参数及温差对强化传热及除垢、防垢性能的影响.结果表明,在实验范围内,换热器换热管内螺旋流态化比螺旋流的传热系数提高15%?20%;颗粒直径5 mm比3 mm的传热系数提高5.4%;颗粒浓度15%(?)比5%(?)传热系数提高15.3%;外径螺旋30 mm比20 mm传热系数提高7.7%;螺距20 mm比60 mm传热系数提高11.1%.随时间连续运行,管内螺旋流态化的传热系数下降幅度远小于螺旋流,表明管内螺旋流态化具有较好的除垢防垢效果.传热温差变化对螺旋流态化强化传热及除垢、防垢性能影响较小.
Through the spiral interpolation method, the spiral flow of fluid in the heat exchange tube of the heat exchanger was generated. The effects of the particle diameter, the particle concentration, the helical structure parameters and the temperature difference on the heat transfer, descaling, The results show that within the experimental range, the heat transfer coefficient of helical flow in heat exchanger tubes increases by 15% ~ 20% compared with that of helical flow, and the heat transfer coefficient of particles with diameter of 5 mm to 3 mm increases by 5.4% ; The heat transfer coefficient increased 15.3% when the particle concentration 15% (?) Was 5% (?) Than the heat transfer coefficient 5% (?); The heat transfer coefficient increased by 7.7%; the helical pitch 30 mm increased by 11.1% Time continuous operation, the tube spiral fluidization of the heat transfer coefficient of decline is much smaller than the spiral flow, indicating that the tube spiral fluidization has good scaling and scaling effect. Heat transfer temperature difference on the spiral fluidization enhanced heat transfer and addition Scale, anti-scaling performance less affected.