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Abstract：Indoor environment separated with down-feed air curtain was numerically simulated and experimentally researched. Indoor airflow and temperature fields separated with air curtain were numerically simulated. Results show that both polluted airflow and thermal air current can be separated with a down-feed air curtain to prevent contaminants from spreading in the room space. In a test chamber, the smoke of burning Tibetan incense served as the source of contaminants, and the probe test shows that 1.0 μm is the prevailing diameter of the smoke particles. During the release of the smoke, the particle concentration of the indoor air was tested with a laser particle counter at the points of three different heights from the floor when the air curtain was running or not. Experimental results show that the higher the test point is located, the lower the particle concentration is, implying that the separating or isolating effect decreases as the air velocity of the curtain reduces along with the height descends. According to both simulation and experimental results, down-feed air curtain can separate indoor environment effectively when the supply air velocity of air curtain is not less than 3 m/s. In order to strengthen separation effect, it is suggested that the supply air velocity be speeded up to 5 m/s. Air curtain technology is usually applied to reduce the entry of outdoor air at gates of stores, workshops and cool warehouses. It is also widely used to prevent workers from breathing dust in mine. In recent years, it is reported that the air curtain has been used to isolate operating zone from non-operating zone in clean operating rooms and control smoke in buildings [1][2][3][4][5] . But it has not been documented that air curtain acted as an airflow wall to isolate contaminant in outpatient departments and sickrooms. In such cases air curtain can be installed around a sickbed to prevent virus and bacterium emitted by patients from spreading, and protect doctors and nurses from infecting.In this study, numerical simulation and experimental research on air curtain were presented. The isolation effects of down-feed air curtain on polluted airflow and thermal air current were simulated. The isolation effects of down-feed air curtain on contaminants were also tested in a test chamber. Numerical simulationThrough comparing vent models, numerical calculation method, equation model, discrete method and discrete format of calculation region and algebraic equation, solution, mesh structures and function of accelerating convergence [6][7][8][9][10][11] , standard K-ε two-equation model and semi-implicit method for pressure linked equations were selected.Considering indoor airflow characteristics, the physical model is simplified as follows.(1) The indoor air is incompressible Newtonian fluid under steady state.(2)The initial indoor air velocity is 0 m/s. The air curtain is used to separate indoor environment without burdening indoor thermal and humidity load. Thus the temperature of the supply air is equal to that of the...

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In the paper, water loop heat pump and air-cooled heat pump were taken as research object to study the effect of part-load ratio on running energy consumption in cold regions. The part-load ratio were respectively 100%, 80%,60%,40% and 20%. The test data was analyzed by dimensionless energy consumption analysis method. And the results showed that, effect of part-load impact on water loop heat pump was larger than aircooled heat pump, especially in Winter. Energy consumption of air-cooled heat pump had linear relationship with part-load ratio, However, it's not suitable for water loop heat pump. Distortion operating point of water loop heat pump was in 80%-100% range of load. Keywords Water loop heat pump; Air-cooled heat pump; Partload ratio; Dimensionless curve)I.978-1-4577-0547-2/12/$31.00 ©2012 IEEE

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Ground-Source Heat Pump systems and tower cooling system have been studied in this paper individually by experiment and simulation using TRNSYS, the influencing factors such as meteorological parameter, cooling tower and subunit construction was analyzed. Results show that the combined system has ability to meet the cooling requirements in II building climate zones, the combined system will have energy-saving and obvious economic benefits by working through the year.