3mm闭式脉动热管传热性能的实验研究

Experimental Research on Heat Transfer Performance of 3mm Closed Pulsating Heat Pipe

为了研究大管径脉动热管的传热性能,设计并搭建了一种闭式脉动热管传热性能的测试装置,管道内径为3 mm,由此实验研究了该装置在加热功率为0～ 90 W范围内的传热性能,通过对冷凝段壁面温度波动特性进行分析,研究了不同加热方式对脉动热管传热性能的影响.结果表明：充液率为27.5％～67.5％时,脉动热管具有较好的传热性能,加热功率为90 W时,各充液率下的热阻值均在0.4℃/w以下;当加热段的输入功率变化（加热功率以波动的方式输入）时,脉动热管的热阻大于对应的以恒定功率加热时的热阻,两者之间的差值随着加热功率的增大而减小;加热功率突变且超过启动功率时,脉动热管很快启动,但达到稳定需要较长的时间,而采用渐进的加热方式时,脉动热管在短时间内即可达到稳定.加热功率较小时推荐采用较小的充液率,加热功率较大时充液率的选择应综合考虑工质的热容量和传热特性.

To investigate the heat transfer performance of large diameter pulsating heat pipe （PHP）,an experimental device for closed PHP with 3 mm inner diameter was designed and constructed.The heat transfer performance of PHP was investigated within heat power range of 0-90 W.The influence of different heating modes on the performance of PHP was tested by analyzing the fluctuation characteristics of wall temperatures in the condensation section.The experimental results indicate that the PHP well performs in a wide charge ratio range of 27.5 %-67.5%,and the thermal resistances get less than 0.4 ℃/W at all tested charge ratios.When the input heat power fluctuates,the thermal resistances of PHP get greater than those heated by constant heat power,and the difference between them decreases with the increasing heat power.If the heat power suddenly reaches beyond the starting power of the PHP,the PHP quickly starts up,but takes a long period to become stable.However,the PHP quickly tends to be stable for gradual heating-mode.The small charge ratio is suggested in the case of lower heat power,otherwise,both the heat capability of working fluid and heat transfer performance ought to be considered.