| As China’s building energy consumption increases,energy conservation,emission reduction and green development are particularly important.The energy consumption of air conditioning system occupies a considerable proportion in building energy consumption,how to optimize the system and how to use renewable energy and low-grade energy to reduce energy consumption is very important to alleviate China’s energy problems.The radiant cooling terminal is an air conditioning system that uses the building surface as the cold source.and conducts heat exchange with indoor wall and personnel surface through radiation and convection heat exchange,it is one of the research hotspots in the field of air conditioning.However,at present,whether in theoretical research or practical application,radiation cooling is not very perfect compared with radiation heating,and there are still many problems to be solved,these problems include: how to improve the radiation cooling capacity to meet the room load requirements under the premise of no condensation;There are differences in the applicable conditions of the calculation methods of radiation cooling capacity,how to calculate the radiation cooling capacity accurately?And how to ensure the comfort of radiation cooling room under the premise of energy saving.In view of the above problems,this paper built a combined system of ground radiant cooling terminal and heat pump solution dehumidification fresh air,and carried out the following research work:Firstly,the operating parameters of the 2019 ～ 2020 summer experiment system were tested and analyzed.On the basis of the experiment of simulating the condensation condition,the measures to prevent the ground condensation are obtained from the two aspects of the system design and the control method.Origin software is used as an auxiliary tool to obtain the operation rules of the radiative cooling terminal under discontinuous and continuous conditions.Finally,the regression model was established by SPSS,and the regression equation of the influencing factors of the ground radiation cooling capacity and the ground radiation cooling capacity was obtained,which provided an effective basis for the promotion and development of the ground radiation cooling terminal.Then the performance of the solution dehumidification subsystem was studied.The influences of new air supply parameters,indoor and outdoor air parameters,system energy consumption on the dehumidification capacity,cooling capacity and energy efficiency ratio of the solution dehumidification unit were discussed,the consequences indicate that under the rated prerequisite,the cooling capacity and EER increases with the increase of air temperature and humidity,in addition,the average hourly cooling capacity provided by the air supply to the room contains 30% of the sensible heat load,to show that the liquid desiccant fresh air unit effective processing,on the basis of indoor latent heat load,also can provide part of the cold,help floor radiant cooling system to achieve maximum cooling capacity.Finally,the indoor comfort,energy saving,control and adjustment of the combined system are studied.In this part,through the calculation of indoor PMV-PPD index,the PMV value is between-0.16 and-0.21,and the PPD value is fixed at 6%,which provides a basis for the evaluation of indoor thermal comfort.;By comparing the combined system with the traditional all-air system,the results show that the average energy saving rate of the solution dehumidification method is 54.8% compared with the traditional refrigeration dehumidification method.End of the floor radiant cooling with liquid desiccant fresh air system,both overcomes the drawback of condensation for ground damp easily,also to a certain extent,solved the problem of insufficient amount of radiant floor cooling,and because of its reasonable and effective use of renewable energy and low grade energy,to break the limitations of radiant floor cooling system,make it in a different building types and regional climate is applied in practical engineering. |
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