Heat transfer performances of the capillary loop pulsating heat pipes with spring-loaded check valve

摘要

Capillary loop pulsating heat pipe (CLPHP) has simple structure, low cost and excellent heat transfer capacity. It is found that three factors, namely gravity, asymmetric heating mode and check valve, can influence the heat transfer performance of a CLPHP. This paper studies the effects of the combination of these three factors on the heat transfer performance of capillary loop pulsating heat pipes with spring-loaded check valve (CLPHP/CV). It is found that any combination of two of these three factors is favorable for forming the stable one-way circulation of the working fluid, which contributes to heat transfer enhancement. While the combination of all these three factors can results in different result. If the spontaneous one-way circulation direction produced by the asymmetric heating mode is opposite to the compulsory one-way circulation direction produced by the check valve, the heat resistance of the CLPHP/CV will be larger than the heat resistance of the CLPHP, and vice verse. When the heat pipe is bottom heated, this feature is more apparent because in this case gravity itself is against working fluid circulation.