基于纳米流体的汽车尾气温差发电系统能效优化研究

Optimization of Energy Efficiency for Automotive Exhaust-based Thermoelectric Generators Using Nanofluid Coolants

汽车尾气温差发电系统(TEG)能将汽车尾气中的热能转化成可储存的电能供汽车再利用,对提高汽车燃油经济性具有重要意义。为了最大程度地提高TEG的转换效率,针对TEG能效开展研究,探究能效影响因素和评价指标之间的关系,并采用多岛遗传算法对TEG进行多目标优化设计,得到系统能效高的TEG。随后,将纳米流体应用于寻优得到的TEG冷端,分析冷端性能优化对系统能效的影响程度。比较加入纳米流体前后的系统各项能效评价指标可知,系统净输出功率提高了6.69%,消耗功率只增加了1.22%,系统能效提高了1.7%,证明了使用纳米流体作为冷却介质的优越性。

Thermoelectric generators(TEGs),which can effectively convert low-quality thermal energy in the exhaust into high-quality electrical energy,have great prospects in the field of improving fuel economy.When TEG is integrated into the vehicle,it consumes a portion of the energy while recovering heat.In order to improve the fuel economy and reduce the fuel consumption,the thermoelectric generator energy efficiency for vehicular application was studied.Besides,the relationships between the influencing factors and the evaluation indexes of the thermoelectric generator energy efficiency were investigated.The muti-island genetic algorithm was used for multi-objective optimization to obtain a TEG with good comprehensive power generation performance.Finally,nanofluid coolants were applied to the cold end of the optimized TEG to obtain better performance.Compared to the traditional TEG,the net output power is enhanced by 6.69% while the power consumption is only increased by 1.22%,and the energy efficiency of the system is increased by 1.7%.