The composite phase change material ( PCMs) used in thermal energy storage with phase change temperature of 5-15 ℃ are proposed in this paper. The material consists of lauric acid ( LA) , decanoic acid ( DA) , tetradecyl alcohol ( TA) and dodecane ( DD) , and the mass ratio of its ingredients is 27. 1∶28. 5∶29. 6∶14. 8, respectively. The composite was prepared by ultrasonic oscillations. The properties of the composite were characterized by cooling process, DSC ( differential scanning calorimety) , thermal cycling test and so on. The results show that degree of superheat of the composite is close to zero so that it can be ignored;phase change temperature and latent heat of the composite are 5. 13 ℃and 154 J/g at 5 ℃/min under a constant and steady stream of nitrogen atmosphere at a flow rate of 10 mL/min, respectively;the composite after 600 cycles deviates the eutectic point without phase separation, so it has better thermal stabili-ty;basic physical properties and thermal properties of the composite were gained by a series of property test. Hereby, the composite shows large potential in thermal energy storage, especially in air-conditioning systems, because of high latent heat, suitable phase change tem-perature, good thermal stability and low cost.%本文研制了一种用于相变温度为5~15℃的储能系统的相变储能材料,该材料由月桂酸( LA )、癸酸( DA )、十四醇( TA)与十二烷( DD)按比例混合经超声波振荡后制得,质量配比为27.1∶28.5∶29.6∶14.8。相变储能材料的性质通过步冷曲线法、差示扫描量热法( DSC)以及热稳定循环测试法等方法来研究。实验结果表明,本相变储能材料的过冷度接近0℃,可忽略不计；在流速为10 mL/min的液氮氛围以及5℃/min的温度变化速率下,相变温度为5.13℃,相变潜热为154 J/g；本材料循环600次后偏离了共融状态,但无分层,具有较好的循环稳定性；通过一系列性能测试,得到了本材料的基本物理性质及热性能。由此可得,本相变复合材料具有较高的潜热、合适的相变温度、较好的热稳定性以及较低的成本,在储能系统尤其是空调系统中表现出了极大的潜力。
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