ABSTRACT

Thermoelectric power generation is an outstanding technology for high- and low-temperature heat recovery. Their packaging, lack of moving parts, direct heat to electrical conversion, and zero-emission are the main benefits for geothermal power generation. The design of a large-scale, ground-based, and segmented annular concentric cylindrical thermoelectric generators (CCTEGs) with produced geothermal fluid are proposed. A mathematical model for thermoelectric power generation is presented, which considers the heat transfer in the interior of a thermoelectric module and the electric current effect, and is solved with Engineering Equation Solver (EES) software. Numerical results show that about 136 kW of power output could be obtained with 500 m length of segmented annular CCTEG under the inlet fluid temperature difference of 130°C. For the same total flow rates and the same total CCTEG length, the in-series layout of segmented annular CCTEG is better than the in-parallel layout in power generation capacity. Flow rate and fluid temperature have a significant effect on the generated power. A higher flow rate ratio of cold fluid to hot fluid will result in higher power capacity. A desirable flow rate ratio of cold fluid to hot fluid is recommended to take as the flow area ratio of cold fluid flow conduit to hot fluid flow conduit when the critical potential increased power generation capacity is taken as 1.0 kW/kg.

摘要

热电发电是高温和低温热能回收的一项杰出技术。它们的包装，缺少活动部件，直接热能转化为电能以及零排放是地热发电的主要好处。提出了一种采用产生的地热流体的大型地面分段分段环形同心圆柱热电发电机（CCTEG）的设计。提出了一种热电发电的数学模型，该模型考虑了热电模块内部的传热和电流效应，并使用工程方程求解器（EES）软件进行了求解。数值结果表明，在130°C的入口流体温差下，采用500 m长的分段环形CCTEG可获得约136 kW的功率输出。对于相同的总流量和相同的CCTEG总长度，分段环形CCTEG的串联布局在发电能力上要优于并联布局。流速和流体温度对产生的功率有重大影响。冷流体与热流体的流量比越高，功率容量越大。当临界电势增加的发电量设为1.0 kW / kg时，建议采用冷流体与热流体的理想流量比作为冷流体流导管与热流体流导管的流量比。冷流体与热流体的流量比越高，功率容量越大。当临界电势增加的发电量设为1.0 kW / kg时，建议采用冷流体与热流体的理想流量比作为冷流体流导管与热流体流导管的流量比。冷流体与热流体的流量比越高，功率容量越大。当临界电势增加的发电量设为1.0 kW / kg时，建议采用冷流体与热流体的理想流量比作为冷流体流导管与热流体流导管的流量比。