Simulation And Performance Analysis For Aliquid Desiccant Air Conditioning System Using Solar Energy Based On TYNSYS

Although the traditional air conditioning system can meet the control requirements of the indoor air temperature and humidity,a series of problems(such as the high energy consumption of dehumidification,the pollution of the environment,the reduction of indoor air quality)appear,which have unavoidably resulted in negative influences Because of the shortage of resources and the increasing requirement of environmental protection,it is more and more important to investigate and employ the new energy-saving and environmental friendly air conditioning system.Especially for the air conditioning systems which are used for industrial processes,the demanding standards are set for not only the temperature precision but also the indoor humidity.This paper takes an industrial workshop as an example,and simulate the system of a liquid desiccant air conditioning system using solar energy based on the TRNSYS simulation platform.The main work can be summarized as follows:Firstly,the principles of the dehumidifier and regenerator of a liquid desiccant air conditioning system have been analyzed.The physical models for the heat and mass transfer process of these two devices are established.The mathematical models of the cross-flow dehumidifier and the counter-current regenerator are built based on the principles of energy conservation,mass conservation law and heat and mass transfer process.,The C language program has been compiled according to the mathematical models,and then the modules of both the dehumidifier and the regenerator are firstly developed on the TRNSYS dynamic simulation platform.The accuracy of the dehumidifier and regenerator modules are verified by the experimental data in the literature.The results show that the relative error between the simulated and experimental data is within 15%,which illustrates that the developed models has ahigher accuracy.Secondly,a liquid desiccant air conditioning system using solar energy is built on the platform of TRNSYS dynamic simulation software.By means of changing the single variable,the influences of the variables such as the inlet air velocity,the flow velocity,the concentration and temperature of the inlet solution on the dihumidification performance have been analyzed.It is found that the amount of dehumidification increases with the increase of air flow rate,the solution's flow rate and concentration,and with the decrease of solution's temperature.The dehumidification efficiency increases with the increase of the solution's flow rate and temperature,and with the decrease of the air flow.For the regenerator in the system,the increase of air flow rate,solution flow rate and solution temperature and the decrease of solution concentration will make amount of regeneration increased.The regeneration efficiency can be improved while both air flow rate and solution's temperature decrease and the solution's flow rate increases.However,the change of solution concentration has little influence on dehumidification and regeneration efficiency.Finally,a marble factory located in the suburb of Jinan has been investigated the application of the liquid desiccant air conditioning system using solar energy in practical engineering.The system has been simulated by means of the TRNSYS simulation model.The results show that the total energy consumption of the system during the three months is 119444 kWh,and the guaranteed solar rate is about 41.78%.By comparing the initial investment and energy consumption cost between the condensate dehumidification system and the liquid desiccant system,it is found that the liquid desiccant system can reach about 40% energy-saving compared with condensing dehumidification system.The liquid desiccant air conditioning system has more advantages in application,and it is worth promoting this type of system in some special industrial processes which have strict demands of dehumidification.The research of this paper can provide technical guidance and design simulation tools for the engineering application of the liquid desiccant air conditioning system using solar energy.