Study On Radiation Terminal And Heat Pump Of CO₂

In recent years, due to increasing of building energy consumption, the environmental pollution is also growing, the main part of which is traditional refrigerant. Moreover, with the improvement of living standards, people propose higher demand about comfort of the AC. Consequently, using new comfort terminal of AC and pollution-free and energy-saving of AC system become hot issues.This thesis mainly studies radiation terminal and CO₂ trans-critical water-water heat pump system, including floor heating and cooled ceiling. By combining of numerical simulation and experiment, it can provide valuable basis for application.Numerical simulation using CFD establishes the physical and mathematical model. For giving initial and boundary conditions, this thesis simulates temperature, velocity and level of comfort. On the experiment, it only concerns the floor heating. Through comparing analysis results of simulation and experiment, it concludes the advantages of radiation terminal and proves the energy–saving and comfort.In addition, on the basis of heat transfer characteristics of radiation terminal, it also simulates CO₂ trans-critical water-water heat pump, and analyses overall effect of system about heating and cooling respectively, including the relationships of COP, flow of water supply, temperature of water supply, and heat transfer capacity. It is concluded that CO₂ trans-critical water-water heat pump system using in this mixed-radiation AC, both for winter and summer, not only protecting environment, but achieving higher COP, saves energy.At last, in this thesis some advices are put forward for further improvement.