Experimental study on the heat transport capability of micro-grooved oscillating heat pipe

• Published in: Case studies in thermal engineering 2021-08, Vol.26, p.101210, Article 101210
• Main Authors: Qu, Jian, Guan, Fengbo, Lv, Yaojie, Wang, Yalin
• Format: Article
• Language: English
• Subjects: Effective thermal conductivity; Heat transfer limit; Microgroove; Oscillating heat pipe
• ISSN: 2214-157X; 2214-157X
• DOI: 10.1016/j.csite.2021.101210

This paper presents an experimental study to investigate the heat transfer limit of a micro-grooved OHP at the vertical bottom heat mode. The internal hydraulic diameter of the micro-grooved OHP is about 2.0 mm, and deionized water was used as a working fluid at volumetric filling ratios (FRs) ranging from 30% to 60%. Experimental results demonstrated that the micro-grooved OHP could significantly enhance the allowable maximum input heat flux before the occurrence of dry-out owing to the capillary action provided by micro-grooved structures to facilitate condensate backflow to the evaporator. The OHP obtained a maximum effective thermal conductivity of 41.8 kW/(m·°C) at 40% FR, corresponding to a dry-out heat flux of 36.9 W/cm2 with respect to the heat transfer limit. The allowable maximum input heat flux was found to be greater than 80 W/cm2 for 50% and 60% FRs, and could be further increased by increasing the OHP turn number. This study provides a promising option to address thermal management demand for high-density power devices.