Research on single-phase flow and two-phase flow boiling cooling performance of microchannel thermal management system with novel Tesla Valve design

In this work, a further modified Tesla Valva type microchannel: open-groove microchannel of sector bump (OGMCSB) was proposed and optimized for efficient thermal management. The single-phase flow and two-phase flow boiling cooling performance of the novel microchannels were studied and targeted correlation for flow boiling heat transfer was proposed. Concluded from the results: the straight open-groove (SOG) structure can intensify the fluid mixing in the primary passage and enhance single-phase convection heat transfer. Under the premise of similar total heat transfer area, the Nu, f and PEC of s = 0.08 mm (width), l = 0.37 mm (position) are 30 %, 44 % and 10 % higher than those of s = 0.175 mm, l = 0.1 mm respectively. Comparing the two-phase flow boiling performance of SOGMCSB-A (s = 0.158 mm l = 0.13 mm) and SOGMCSB-B (s = 0.2 mm l = 0.2 mm), The maximum wall superheat of SOGMCBS-B is over 23 % lower and the maximum heat transfer coefficient is about 47 % higher than that of SOGMCSB-A. More frequent bubble/vapor slug segmentation and intense churn flow in SOGMCSB-B promote the rewetting of channel surface and improve boiling heat transfer. However, such characteristic also brings additional boiling instability, resulting in 50 % larger total pressure drops and the fluctuation extent in SOGMCSB-B. The proposed boiling heat transfer correlation shows ideal accuracy and the MAE is only 7.6 %.