Thermal Independent Humidity Energy Simulation And Experimental Study Of Air-conditioning Systems

Now the society, the shortage of the energy and the worsening of the environment have become a worldwide question. In the field of HVAC system, the applications of energy- saving and environmental protection technology have become the key points at home and abroad. Nowadays, the traditional refrigeration air-conditioning systems are facing a lot of questions and challenges, which aren't solved by themselves, for example, energy-saving and environmental protection, deterioration of indoor air quality, health and safety of people, and so on. Heat and humidity independent control air conditioning system is established under this background, wipes off the sensible load and latent load separately, realizes the temperature and humidity independent control, meets the temperature, humidity, IAQ request according to the energy saving and environmentalism aspect, it is a new air-conditioning way.The paper studies the two room environment control strategies which are heat and humidity joint treatment and heat and humidity independent treatment discusses the principle of heat and humidity independent control air conditioning system on the base of system summary, studies the running principle; strongpoint and shortcoming of constitute equipment. Then analyses air-conditioning system efficiency from the view of thermodynamics, compares the ideal efficiency of cooling dehumidification system and heat and humidity independent control air-conditioning system by way of calculation, studies the causes of high efficiency of the later system.On the foundation of this, the paper carries exergy analysis of heat and humidity independent control air-conditioning system, establishes air-conditioning equipment exergy analysis models from the balanced equation about this system, analyses evaporative cooling cold water maker from original to improved respectively, discusses the changes and courses about exergy efficiency. Then carries the exergy analyses about dry fan coil/fresh air system, cooling dehumidification/radiant cooling system, liquid dehumidification/radiant cooling system, studies the exergy efficiency of each device, discusses the main factors of exergy losing. Then the paper takes exergy calculation of common air-conditioning system and dry fan coil/fresh air system and cooling dehumidification/radiant cooling system, compares the whole systems' exergy efficiency, takes the conclusion that heat and humidity independent air conditioning system are always energy saving more than common air conditioning system, the degree depends on the whole system's design process and devices' energy saving degree.Then, this paper establishes the simulation systems using the software of TRNSYS, simulates the dry fan coil/fresh air system, cooling dehumidification/radiant cooling system, rotate wheel dehumidification/radiant cooling system with the lab room as the center component. Then studies these systems running and room's heat-humidity circumstances, analyses the three systems energy consumption so that find the energy consume main part. Besides, models the experiment project, gains the perfect heat and humidity circumstance and provides the foundation for experimental study later.Finally, the author experiments the reconstructive fan coil/radiant cooling system according to fact. Discusses the room overall temperature and gradient temperature in different water temperatures and radiant boards, studies the condition of appearing condensation phenomena and measures to avoid condensation; discusses the proportion of radiant heat exchange and convection heat exchange using radiant cooling, imposes the water parameters of fan coil and radiant board, studies both parameters. The experiment indicates that beforehand dehumidification can avoid condensation and when room's heat humidity circumstance is fine the radiant board bears the 60% room cooling load.