换流阀冷却用相变乳状流体的制备及其性能

Preparation and Performance of Phase Change Dispersion for Converter Valve Cooling System

摘要:

为提高换流阀冷却能力，以相变材料（高级脂肪酸酯CrodaThermTM 47和CrodaThermTM 53）、乳化剂（硬脂醇聚醚BrijTM S2和油醇聚氧乙烯醚Sympatens AS-100）和成核剂（聚乙烯醇）以及去离子水为原料，制备了换流阀冷却用相变乳状液。探究了相变乳状液的配方和制备工艺等对相变乳状液性能的影响，确定了最佳配方（以相变乳状液的总质量计，相变材料、乳化剂、成核剂和去离子水的质量分数分别为16%、1.6%、2.4%和80%）和剪切工艺（剪切速率50 ks-1，持续5 min）。对制备的换流阀冷却用相变乳状液进行了对流换流系数、电导率、带电稳定性以及与冷却系统兼容性等分析，结果表明，与去离子水相比，所制备的相变乳状液的表观比热容提升了约50%，换热能力提升了2倍左右。其电导率、绝缘耐压等关键性能参数均能满足高压条件下换流阀冷却的应用要求。

Abstract:

In order to improve the cooling capacity of the converter valve phase change dispersion for converter valve cooling system are prepared with phase change materials(CrodaThermTM 47 and CrodaThermTM 53), emulsifiers(BrijTM S2 and Sympatens AS-100), nucleating agents(Polyvinyl alcohol) and deionized water as raw materials. The effects of different factors such as formulation and preparation technology of phase change dispersion on the properties of phase change dispersion are studied by experimental method. The best formulation (based on the total mass of phase change emulsion, the mass fractions of phase change material, emulsifier, nucleating agent and deionized water are 16%, 1.6%, 2.4% and 80% respectively) and shear process (shear rate 50 ks -1, lasting time 5 min) are determined. The convective heat transfer coefficient, conductivity, voltage stability and compatibility with cooling system are analyzed. The results show that the apparent specific heat capacity of the new phase change dispersion is 50% higher than that of deionized water, and the heat transfer capacity is 100% higher than that of deionized water. The key performance of the new phase change dispersion such as electroconductibility, insulation and withstand voltage parameters can meet the cooling application requirements of the converter valve.