摘要
以开槽螺旋叶片转子为研究对象,对装有空隙比S=0.0、3.0、6.0和10.0间隔排布转子串换热管的传热和阻力特性进行了实验研究。结果表明,装有空隙比S=0.0的整串转子串换热管的努塞尔数比同雷诺数下光管经验公式值提高了0.8～1.2倍,但阻力系数也提高了55%左右;转子串间留出一定间隙,虽会减弱管内流体扰动使换热管传热性能有所降低,但也显著降低了管内压降。采用综合评价指标(PEC)对4种空隙比转子串的传热和阻力特性进行综合比较,在实验雷诺数范围内,当雷诺数较低时,适当增加转子串的空隙比能够提高其综合传热性能;当雷诺数较高时,在转子串间留出间隙会使其综合传热性能低于整串转子。
The heat transfer and friction characteristics of tubes fitted with full length and regularly spaced grooved helical lobe rotor strands, with involved space ratios of 0.0, 3.0, 6.0 and 10.0, have been investigated experi- mentally. The Nusselt numbers of tubes with full length strands increased by factors of 0.8 - 1.2 times the empiri- cal correlation results for plain tubes with the same Reynolds numbers, while the friction factor also increased by a- bout 55%. The introduction of free spacing length weakened the disturbance of fluid flow, resulting in a decrease in heat transfer characteristics and tube side pressure drop at the same time. Performance evaluation criteria （PEC） of strands with different space ratios were compared, and the results indicated that in the experimental Reynolds number range, an increase in space ratio resulted in a beneficial increase in PEC for low Reynolds number, while the PEC values of regularly spaced strands were lower than those of full length strands when the Reynolds number was relatively high.
出处
《北京化工大学学报（自然科学版）》
CAS
CSCD
北大核心
2013年第1期103-108,共6页
Journal of Beijing University of Chemical Technology(Natural Science Edition)
基金
国家科技支撑计划重大项目(2011BAA04B02)
北京市自然科学基金(3102023)
关键词
转子
空隙比
强化传热
综合评价指标
实验研究
rotor
space ratio
heat transfer enhancement
performance evaluation criteria （PEC）
experimental investigation
