Using phase change materials (PCMs) for passive cooling is an effective thermal management technique as they absorb and release large amount of latent heat. However, PCMs have low thermal conductivity and liquid leakage often occurs after the solid-liquid phase transitions. In this study, a Wood’s alloy/expanded graphite composite PCM was developed to achieve desirable thermal performance. The thermal conductivities of the composite samples were measured, based on a ...
A new composite phase change material for cold thermal energy storage applications is described in this paper. The authors combined dodecane into hydrophobic fumed silica to create a form stable PCM. Physical characteristics were studied using scanning through electron micrographs and Fourier transformation infrared. A thermal analyzer was used to measure the thermal conductivity of the composite, which was a desired low value needed for this type of application. An ...
The goal of this work was to produce a new high performance PCM, using a combination of RT 100 (paraffinic hydrocarbons) with expanded graphite (EG). The resulting composite performed extremely well in quality testing. Thermal conductivity was measured using the TPS method, and was found to be much higher in the composite than it was in the basic RT 100 materials. Thermal conductivity did not decrease during melting cycles. The ability of ...
This paper focuses on the creation of a new composite phase change material, paraffin-silica (SiO2)/graphene oxide (GO) through a two step process for potential use as a heat transfer fluid in direct absorption solar collectors. The resulting composite is composed of spherical capsules, and has the GO embedded within the SiO2 shell. Thermal conductivity testing with the TPS instrument revealed that the composites had excellent thermal characteristics and stability. ...
The purpose of this study was to measure the thermodynamic properties of 1-hexyl-3-methylimidazolium tetrafluoroborate ([HMIM]BF4) and its graphene-dispersed ionic liquid based nanofluids (Ionanofluids) from room temperature to 200 °C. A thermal analyzer measured the thermal conductivity of the samples using the transient plane source (TPS) method. Results showed that the thermal conductivity of [HMIM]BF4 and the GE-dispersed Ionanofluids increased linearly with temperature, and with mass particle fraction. It ...
