Prof. Airong Li
Southwest Petroleum University, China
Title: Preparation of highly stable paraffin wax-water emulsions using different emulsifier mixtures and its properties for heat-transfer
Abstract:
In solar thermal management systems
(TMS), phase change material emulsions (PCMEs) were focused as an intermediate medium to achieve efficient
heat utilization. Hence, paraffin wax with a melting point (Tm) of
55 ℃ was used as the phase change material to prepare PCME samples by using an
ultrasonic mixed film forming method. The thermal properties of PCME samples prepared by Steareth-100/Steareth-2 (PCME-S) and
Tween80/Span60 (PCME-T) emulsifiers were investigated using a differential
scanning calorimetry (DSC). PCME-S showed a low supercooling and its maximum specific heat capacity was 9.136 J/g·K at 55 °C. The thermal stability was evaluated by a serial of heating and cooling cycles. PCME-S had significantly
better thermal stability and the particle size distribution remained nearly
same after 480 heating and cooling cycles. Besides, the
electrical conductivity, corrosiveness and rheological properties of PCME-S
were determined. Moreover, PCME-S had a low viscosity of 2.17 mPa·s at 55 °C with a shear rate
of 100 s-1.
Finally, the evaluation of heat-transfer presented that PCME-S had a higher
efficiency than water, and the ideal pump power ratio PPCME-S/PWater was 0.33.
Keywords: Paraffin wax; Steareth-100/Steareth-2;
Phase change material emulsions; Thermal stability; Specific heat capacity
Biography: