Thermal performances of pumped thermosyphon loops with evaporator configured by serpentine ribbed channel with and without internal effusion

Abstract

Thermal performances of two pumped thermosyphon loops (PTL) with the evaporator configured by the serpentine ribbed channel with or without the internal effusion are studied. The boiling flow structure, thermodynamic cycle, phase-change heat transfers, and thermal resistance of each loop are compared. With effusion, the evident pressured-drop reduction across the evaporator has led to the decreased boiling temperature and the shrunk sub-cooling region in the evaporator to promote the PTL performance. The merit index that assesses the reductions of loop thermal resistance and total pumping power consumption affirms the considerable thermal performance improvement by the internal effusion in evaporator. Relative to the PTL without effusion, the loop thermal resistance is reduced by 3–32% with the coefficient of performance raised by 14–207%.