石蜡/水相变乳液的制备与性能

Preparation and properties of paraffin/water phase change emulsion

低温石蜡/水相变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,可取代水作为传热介质应用于集中供冷系统中,降低二次循环水泵的运行能耗。基于集中供冷系统的应用要求,选择不同的组分制备相变乳液,包括石蜡、表面活性剂以及晶核剂,并研究其组分含量对乳液分散相粒径分布、热力学性能与流变性能的影响,最终确定相变乳液的制备方法与性能参数。采用所述方法制备的相变乳液具有良好的稳定性,其储能容量为水的2~6倍,且过冷度不高于2K。

A paraffin/water emulsion is a phase change slurry(PCS),which uses both the sensible heat capacity of the carrier fluid and the latent heat capacity of the phase change material(PCM),is pumpable and has a high energy storage density.The energy consumption of central cold supply networks could be reduced when applying lowtemperature paraffin phase change emulsion as a heat transfer fluid.Based on the application requirements,different components have been selected to prepare emulsions,inclusive paraffins,surfactants and nucleating agents.The impact of their fractions on the emulsion properties has been studied,namely on the droplet size distribution,thermal properties and rheological behaviors.Finally,the emulsion components and their suitable fractions have been determined for preparing a stable paraffin/water emulsion with a energy storage density 2-6 times water and a subcooling degree lower than 2 K.