旋流条件下螺旋弹性铜管振动强化传热性能分析

Vibration-enhanced heat transfer performance analysis of helical elastic copper tube under swirl condition

为了充分利用流体诱导螺旋弹性铜管(helical elastic copper tube,HECT)振动增强传热,以获得更高综合传热性能的HECT换热器装置,基于安装正向螺旋引流板的螺旋弹性铜管(helical elastic copper tube-forward spiral baffle,HECT-FSB)换热器和逆向螺旋引流板的螺旋弹性铜管(helical elastic copper tube-reverse spiral baffle,HECT-RSB)换热器,采用双向-流固耦合法,研究了旋流条件下入口流速(U_(in))对HECT振动强化传热性能的影响。研究表明:U_(in)在计算范围内增加,HECT的振幅增大、传热系数提高,HECT换热器的进出口压降增大、PEC(performance evaluation criteria)值减小;HECT-RSB换热器的HECT振幅和传热系数、进出口压降明显高于HECT-FSB换热器。HECT-FSB换热器的PEC值高于HECT-RSB换热器,振动强化传热性能更佳,当U_(in)=0.3 m/s时,PEC值高出了9.00%。HECT-RSB换热器的综合传热性能因子JF值最大,综合传热性能最佳,与已发表文献中的换热器相比,U_(in)在计算范围内综合传热性能因子JF值平均提升了2.7%。该研究可为HECT换热器装置综合性能的提升提供技术支撑。

Here,to fully utilize fluid induced helical elastic copper tube(HECT)vibration enhanced heat transfer and obtain a HECT heat exchanger device with higher comprehensive heat transfer performance,a bidirectional fluid-structure coupled method was used to study effects of inlet flow rate(U_(in))on vibration enhanced heat transfer performance of HECT under swirl condition,based on helical elastic copper tube-forward spiral baffle(HECT-FSB)and helical elastic copper tube-reverse spiral baffle(HECT-RSB).The study showed that with increase in U_(in)within its calculation range,amplitude of HECT increases,heat transfer coefficient increases,inlet-outlet pressure drop of HECT heat exchanger increases,while performance evaluation criteria(PEC)value decreases;HECT amplitude,heat transfer coefficient and inlet-outlet pressure drop of HECT-RSB heat exchanger are obviously higher than those of HECT-FSB heat exchanger;PEC value of HECT-FSB heat exchanger is higher than that of HECT-RSB,the former’s vibration enhanced heat transfer performance is better,when U_(in)=0.3 m/s,the former’s performance is 9.00%higher;HECT-RSB heat exchanger has the max JF factor and the best comprehensive heat transfer performance,compared with heat exchangers in published literature,when U_(in)is within its calculation range,the former’s JF factor averagely increases by 2.7%;this study can provide technical support for improving comprehensive performance of HECT heat exchanger devices.