ISSN Online: 2379-1748
ISBN Flash Drive: 978-1-56700-431-1
ISBN Online: 978-1-56700-430-4
First Thermal and Fluids Engineering Summer Conference
EFFECTS OF CROSS-SECTION GEOMETRY ON THE THERMAL PERFORMANCE OF A PULSATING HEAT PIPE
摘要
In this study, the thermal performance and flow characteristics of the flat-plate micro pulsating heat pipe (PHP) with different cross-section geometry were investigated through experiments. Two types of silicon-based PHPs, which have a circular and square channel, were fabricated using a micro-electromechanical fabrication technique. The thermal performance of the PHPs charged with ethanol and FC-72 was tested at vertical orientation. The overall thermal performance of the square channel PHP is better than that of the circular channel PHP. When the working fluid is ethanol, the minimum thermal resistance of the square channel PHP is about 3.3 K/W, which is 3.2 times smaller than that of the circular channel PHP. The square channel PHP achieves maximum effective thermal conductivity of 727 W/m · K, which is the 4.9 times higher than thermal conductivity of silicon. More active movements of the menisci in the square channel PHP were observed from the flow visualization due to the corners of the square channel delay complete dryout at the evaporator and act as nucleation cavities.