Document Type : Research Paper


1 Mechanical Engineering Department, University of Technology - Iraq

2 Mechanical Engineering Department, Baghdad,Iraq


Experiments in microchannel heat sink were carried that examine the deionized water two-phase boiling heat transfer. The heat sink consisted of a single microchannel having 300μm wide nominal dimensions and 300μm height (hydraulic diameter of 300μm). The heat sink formed of oxygen-free copper with 72mm length and 12mm width. Experimental operation conditions spanned the heat flux (78-800) kW/m2, mass flux (1700 and 2100) kg/m2.s at 31K subcooled inlet temperature. The boiling heat transfer coefficient is measured, and compared with existing correlations. The results show that higher mass flux leads to a higher boiling heat transfer coefficient and the dominants mechanism is convective boiling. In addition, it was found that an existing correlation provides a satisfactory prediction of the heat transfer coefficient.


Main Subjects

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