碳纳米管薄膜热电发电机设计及耦合分析

Design and coupling of carbon nanotube membrane thermoelectric generator

为解决微小型器件电源体积大、质量重、集成难等问题,利用碳纳米管薄膜材料的热电特性,设计了一种新型的薄膜式热电发电机,可将热气流直接转化为电能。建立了薄膜热电发电机物理模型,研究了热电发电理论和控制方程,对碳纳米管薄膜热电发电单元进行有限元仿真,分析了输出电压和输出功率的变化规律。提出了减小内阻的方法,为改进碳纳米管薄膜热电发电实验模型提供理论依据。利用浮动催化化学气相沉积法制备了导电性较好的透明碳纳米管薄膜,其热电特性与仿真结果一致。碳纳米管薄膜柔韧性较好,将多个发电单元串联连接,构建圆柱体、截顶圆锥体等多种薄膜式热电发电机结构,易与微光机电系统集成,具有广阔的应用前景和实用价值。

In order to solve the power problems of miniature devices such as great volume, heavy weight and dif- ficult integration, the novel membrane thermoelectric generator （ TEG ） was designed by utilizing the thermoe- lectric properties of carbon nanotube （ CNT ） membrane. It could directly convert the thermal gas flow to the electric energy. The physical model of the membrane TEG was constructed. The thermoelectric theory and governing equations were researched. The CNT membrane thermoelectric cell was simulated by the finite ele- ment method, and the change trend of output power and voltage were analyzed. The methods of reducing the internal resistance were put forward, which could provide the theoretical foundation for optimizing the experi- mental model. The highly conducting, transparent CNT membrane was synthesized by the floating-catalytic chemical vapor deposition. The thermoelectric properties were consistent to the simulation results. The CNT membrane had fine pliability, so the cylinder or truncated cone structure of membrane TEG could be construc- ted by connecting many cells in series. It was easily integrated with micro-optical electromechanical systems, and had wide applied prospect and practical value.