Simulation and Experimental Study on Vacuum Negative Pressure Infusion of Working Fluid for Micro Heat Pipes

Optimum filling ratio as an important parameter has a great effect on the heat performance of pipes. Especially for micro pipes with only hundreds microliters internal volume, their optimum ratios are hard to be obtained without accuracy order microliter magnitude. This paper simulated process water working fluid, and change regularities pressure, velocity volume fraction liquid were investigated. The simulation results show that flow pattern plug is key leading infusion error. liquid-vapor slugs caused pulsation pressure velocity, which would make flux uncontrollable accurately. maximum relative error in reached -1.8%, -1.6% was due slug flows against 0.1% phase change. To eliminate influence formed under negative novel charging method buffer pipeline proposed. Then test five groups different quantities (20μL, 25μL, 30μL, 40μL, 50μL) two MHPs about 100μL carried out, suggest mean absolute below 1μL.