Research And Optimization On Thermoelectric Generation Using The Waste Heat Of Water Heater Flue Gas

Thermoelectric material is a direct conversion of heat and electricity of energy materials.Thermoelectric generation device has a simple structure， no noise， no pollution， smallsize， high reliability， etc. Power generation technologies based on thermoelectric materialsis one of the ways of the most promising heat recovery technology.With the energy andenvironmental problems becoming more and more serious， how to maximize theimprovement of energy efficiency on the premise of no hazard to the environment has becomethe concern of countries in the world. Researchers around the global have givenunprecedented attention to the research on themoelectric technology. About seventy percent ofthe energy in the existing energy system is disspated to environment in the form of waste heatthat is a great waste of energy. On the other hand， it has large energy-saving space to takeuse of the waste heat. Thermoelectric generation technology is friendly to the environment. Itis a solid-state energy conversion means and has no noise， no wear， no pollutant emission，small size， light in weight， portable， long life and no maintenance. Particularly it has nolimit to temperature so the unique advantage makes more and more people see its potentialityin the waste heat recovery field. Thermoelectric conversion efficiency is not high because ofthe limitation of thermoelectric materials and it has few studies on the match of variousparts of thermoelectric generators， so it is necessary to conduct a much deeper study onthermoelectric. This paper introduced the worldwide research on thermoeletric technology，analysed the potentiality of thermoelectric generation system in application of waste heatrecovery. The main research work and conclusions include the following:Testing platform of thermoelectric generation system has been established on the basis ofthe basic theory of thermoelectricity. The heat chip which designed by ourselves works as theheat source， and the cold side heat is dissipated by the heat sink. Testing the uniformity oftemperature distribution of heat chip surface by experiment combined with Infrared thermalimage technology， and the results show that temperature in the center of the heat chip washigher than the surroundings and temperature difference increased while the heater powerincreased. However， the temperature difference is still acceptable in our experiment.We put the thermoelectric generator system into application of the recovering of exhaustheat produced by Gas Water Heater. The specific install area of the thermoelectricgeneration system has been fixed by the temperature distribution testing experiment.Plus，the output power of the thermoelectric generation system at different water flow and gas pressurehas been tested. The comparision of the two manners of module connections with the outputpower effects shows that: series is better than in parallel.The regularity for change of output power， converting efficiency and energy efficiencyof the thermoelectric generation system has been studied with the working conditions likedifferent load resistance、temperature difference and so on with the experimental approach inthis paper. The study of the heat recovering of Gas Water Heater system with thermoelectricsystem has enriched the research content about thermoelectric generation on heat recoveringand some practical methods and conclusions about low heat recovering of thermoelectricgenerator has been shown.