石蜡/水相变微乳液流变性能研究

Rheological Study of Paraffin/Water Phase Change Emulsion

低温石蜡/水相变微乳液作为一种潜热蓄冷流体,具有储能密度高、可泵送的特点。本文采用凝固点为9℃的石蜡作为分散相,在非离子表面活性剂的作用下制备石蜡/水相变微乳液,并通过自制的泵送实验平台研究微乳液在石蜡分散相呈固态、液态以及在固-液转变过程中的流变性能。实验结果表明,在不同温度情况下,微乳液在紊流区域经过水平管道的摩擦系数与雷诺数关系曲线与Metzner模型计算结果相符合。在流速为0.5~1.0 m·s^(-1)的情况下,石蜡质量分数为30%的微乳液在管道中引起的水头损失为水的水头损失的1.5~3倍。

A paraffin/water emulsion has been studied as a latent heat storage and transfer medium for comfort cooling applications.The emulsion is a binary system where a paraffin with a freezing peak point of 9°C is distributed in water and maintained in dispersion by a surfactant.Its rheological behavior has been investigated in a test rig at different phases of the paraffin regarding the application requirements in pumped systems.It was found that the Metzner model can be used to estimate the correlation between the friction factor and Reynolds number in the turbulent region.The emulsion containing 30%paraffin causes 1.5~3 times the pressure drop of water at a flow rate of 0.5~1.0 m·s^（-1）.