Fundamental Research On Air Carrying Energy Radiant Air-conditioning System Based On Thermodynamic Method

It is of great practical significance to study the energy efficiency of air-conditioning systems in order to improve the energy crisis of today's society.Radiant air-conditioning system is a kind of energy saving air-conditioning system,and it has been widely applied in practical engineering.The air carrying energy radiant air-conditioning system(ACERS)is a new kind of radiant air-conditioning system,which has high performance on indoor thermal comfort and condensation prevention.ACERS has good application prospects.In this paper,the thermodynamic property of ACERS is explored,which is aimed at anlyzing the economy performance of ACERS.Firstly,the three lumped-parameter models of ACERS for the average temperature of radiant orifice plate,lowest temperature under summer condition and highest temperature under winter condition are established,which are verified by computational fluid dynamic(CFD)simulation and experiments.Moreover,the temperature distribution uniformity of radiant orifice plate is analyzed based on the proposed models.Results show that the accuracy of the proposed lumped-parameter models are relatively high.And the temperature distribution uniformity is better compared with traditional metal radiant plate,leadings to preferable cooling or heating effect.Secondly,based on the heat transfer process of the orifice plate and the exergy analysis method of traditional mental radiant panel and convective air-conditioning terminal,the algorithm of room input exergy for ACERS is proposed.The complete exergy flow of ACERS consists of four exergy,including room input exergy,air-conditiong input exergy,terminal system input exergy and product exergy.And the exergy cost analysis model of ACERS is established by exergy cost analysis method,also the energy cost model of ACERS is established.Thirdly,the unit exergy cost and unit cooling or heat cost of ACERS under three typical working conditions are calculated,which are compared with capillary radiant air-conditioning system of office building and a combined system of split air-conditioning with floor radiant air-conditioning of residential building.It is found that the overall exergy economic and energy economic performance of ACERS is superior to the other two radiant air-conditioning systems.Finally,based on the multi-objective comprehensive analysis method,the omprehensive thermal economy of three radiant air-conditioning systems are analyzed as the unit cooling or heat cost,unit exergy cost,carbon dioxide emissions,construction difficulty and maintenance and management difficulty to be the indicators.The result indicates that ACERS has a higher overall score and better comprehensive thermal economic performance compared with the other two radiant air-conditioning systems.