Thermoelectric performance study on a heat pipe thermoelectric generator for micro nuclear reactor application

Abstract

Summary Heat pipe cooled reactor is designed to meet the future energy demands with many unique advantages such as modularization, solid and static state, high reliability and passive safety. In the innovative nuclear reactor design, heat pipes are used to cool the reactor core and transfer the fission heat passively, thermoelectric generators (TEGs) are utilized to achieve static energy conversion. In this article, a finite element model is established to investigate the detailed TEG thermoelectric performance coupled with heat pipes. A temperature field and flow field coupling model is used to simulate the heat transfer performance of the potassium heat pipe including a heat pipe wall, wick and vapor region. A heat pipe TEG experimental setup is established and the steady‐state experiment is conducted. The experimental setup is selected as the numerical simulation object and the simulated results are compared with the experimental data to verify the numerical model. The maximum simulation error is within 5%. Based on the verification and validation, the steady‐state thermoelectric performances, the effect of contact thermal resistance and external load on the skutterudite TEG thermoelectric performances are investigated. The detailed heat flux distributions, temperature distributions and potential distributions are researched in the steady‐state simulation. The temperature distributions of the TEG cross section are centrally symmetrical and the horizontal temperature difference is 26°C. The temperature difference introduced by thermal resistance at the TEG hot side increases from 33°C to 94°C with the increasing heat flux through TEG module. The influence of thermal resistance on TEG hot side is more significant than that on TEG cold side. The effect of external load on TEG output characteristics is investigated under different heat flux conditions. With the increase of heat flux from 60 to 166 kW/m2, the temperature difference of TEG module and p‐n unit increase by 432°C and 348°C, the thermoelectric conversion efficiency is improved from 3.6% to 8.5%, and output power increases by 20 W, respectively. The research results are of guiding significance for exploring the application potential of TEGs in the static heat pipe cooled reactor. This work provides research foundations for the multiphysics coupling analysis of the micro heat pipe cooled reactor.

Evolution of Thermoelectric Generators: From Application to Hybridization

“…We present an overview of the existing TEGs applied to different pipe types in Figure . [ 246–250 ] In Figure 6a, Li et al. [ 246 ] successfully demonstrated large‐diameter wafers with uniform thermoelectric properties for thermoelectric modules for high‐temperature applications.…”

“…Reproduced with permission. [ 248 ] Copyright 2021, Wiley‐VCH. d) Flexible TEGs applied to the outside of pipes of different shapes.…”

“…Here is a description of TEGs which are used in our lives in Figure 5. [233][234][235][236][237][238][239][240][241][242][243][244][245][246][247][248][249][250] In Figure 5a, Indab et al [238] placed 12 commercial TEGs inside aluminum window frames for heat harvesting. the hot side of the TEGs absorbed heat through the sun's rays between 1:00 p.m. and 3:00 p.m.…”

“…c) Application of TEGs for potassium heat pipe. Reproduced with permission [248]. Copyright 2021, Wiley-VCH.…”

Preliminary conceptual design and analysis of a 100 kW e level Nuclear Silent Thermal‐Electrical Reactor ( NUSTER ‐100)

“…With the maturity and development of heat pipe cooled reactor, heat pipe cooled reactors will have broad application prospects in marine applications. Many researchers are also committed to applying heat pipe reactors to UUVs as their power source 21 …”