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
INWARD MELTING AND FREEZING OF ADDITIVE-ENHANCED PHASE CHANGE MATERIALS IN SMALL DIAMETER CYLINDERS
Abstract
The inward solidification and melting of a commercially available phase change material (PCM) is characterized within a 14 mm diameter cylindrical enclosure oriented vertically. During freezing and melting, the PCM temperature is monitored at the center while the external wall temperature is changed abruptly. The volume fraction of the PCM undergoing phase change is characterized by measuring the expansion and contraction of the PCM using an electronic pressure transducer. Using this custom-built experimental apparatus, the effects of superheating and sub-cooling on the solidification and melting processes have been studied. Additionally, the inclusion of nano-additives to enhance the PCM thermal conductivity has been investigated and characterized including the effects of thermal cycling on additive-enhanced PCM performance. More than a 40% decrease in solidification time and a 45% decrease in melting time have been demonstrated with the addition of graphite nano-platelets at a concentration of 3% by weight.