TiO_2纳米颗粒对相变悬浮液流变和导热系数特性影响研究  

Study of the Influence of TiO_2 Nano-particles on the Rheology and Heat Conduction Coefficient Characteristics of a Phase-change Suspension

作　　者：靳健[1] 刘沛清[1] 林贵平[1] 丁玉龙[2] 

机构地区：[1]北京航空航天大学航空科学与工程学院,北京100191 [2]利兹大学颗粒科学与工程学院

出　　处：《热能动力工程》2010年第2期172-176,共5页Journal of Engineering for Thermal Energy and Power

基　　金：国家自然科学基金资助项目(50436020)

摘　　要：通过实验方法研究了掺入TiO2纳米颗粒的相变悬浮液粘性和导热系数。研究表明,当纳米颗粒浓度不超过5%时,悬浮液仍可被视为牛顿流体,悬浮液的粘性随纳米颗粒浓度增加以非线性方式增加;当纳米质量颗粒浓度为5%时,相变悬浮液的粘性提高约23%。纳米颗粒的加入能够显著提高相变悬浮液的导热系数,当纳米颗粒质量浓度为5%时,相变悬浮液导热系数提高约7%。当纳米颗粒浓度较低时,纳米颗粒对相变悬浮液导热系数的提高幅度要高于对水的提高幅度。文中从不同方面分析了使用这种新型悬浮液作为传热工质的优势。By using an experimental method, studied were the viscosity and heat conduction coefficient of a phase-change suspension after it has been mixed with TiO2 nano-particles. The research results show that when the concentration of the nano-particles does not exceed 5%, the suspension can still be viewed as a Newtonian fluid and its viscosity will increase nonlinearly with an increase of the concentration of the nano-particles. When the concentration of the mass nano-particles equals to 5%, the viscosity of the phase-change suspension will rise by about 23%. The addition of the nano-particles is capable of significantly improving the heat conduction coefficient of the suspension in question. When the concentration of the nano-particles is 5%, the heat conduction coefficient of the phase-change suspension will increase by about 7%. When the concentration of the nano-particles is relatively low, the growth margin of the heat conduction coefficient of the phase-change suspension caused by the nano-particles will be higher than that of the water. The authors have analyzed from different perspectives the advantages of using the new type of suspension to serve as a heat transfer working medium.

关 键 词：相变微胶囊 纳米颗粒 纳米流体 牛顿流体 潜热 

分 类 号：TK124[动力工程及工程热物理—工程热物理]