Experimental investigation on thermal characteristics of a novel loop heat pipe for cooling high heat flux electronic chips. (15th May 2022)

• Record Type: Journal Article
• Authors: Xiong, Kangning; Meng, Like; Wang, Shuangfeng; Zhang, L. Winston
• Is Part Of: International journal of heat and mass transfer. Volume 187(2022)
• Publication Date: 2022-05-15
• Subjects: Loop heat pipe -- Flat evaporator -- Thermal characteristics -- Orientations -- Heat sink temperature -- Flow rate; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2022.122569
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: A novel flat ELR evaporator LHP has been proposed and tested. The novel LHP can overcome the shortcoming of traditional flat ELR evaporator LHP. The LHP was investigated at different orientations and heat sink conditions. The LHP can effectively dissipate a maximum heat load of 750 W (83.33 W/cm 2 ). Abstract: A novel flat evaporator loop heat pipe (LHP) has been designed and proposed to overcome the shortcoming of the traditional flat evaporator LHP that cannot operate normally in some positive gravity direction (especially +90º), and to solve the heat dissipation challenges of high heat flux electronic chips. The vapor channels of the capillary wick for the novel LHP were arranged in double rows. And a 1 mm thick smaller particle size copper powder embedded with two 0.5 mm thick stainless steel rings was sintered on the internal surface of the compensation chamber. The thermal characteristics of the novel LHP were investigated at nine different LHP orientations at heat sink temperature from 10 to 40 °C and flow rate of the cooling water of 1 to 4 L/min. The experimental study indicated that the novel flat evaporator LHP can operate normally in some positive gravity directions (especially +90º). And the LHP orientations have a significant influence on the junction temperature and the thermal performance of LHP. Compared with other LHP orientations, the junction temperature at the most favorable LHP orientation was only of 83.60 °C under the highest heat load of 750 W (83.33 W/cm 2 ). The junction temperature increased from 86.67 to 88.64 °C at the maximum heat load of 750 W when the heat sink temperature was increased from 10 to 40 °C. The effect of flow rate of cooling water on the thermal characteristics of the novel LHP was less considerable in the range from 1 to 4 L/min