The Feasibility Research On Recycling Hot Air In Winter About Upper Space Of Railway Station

With the rapid development of the railway industry, the energy consumption of heating will increase dramatically in railway stations, while building energy efficiency requirement is more stringent in the future at our state. Therefore, the application of new technologies are energy-efficient and reduce emissions is essential. According to measurements of the temperature in the vertical space of large space building, there is a significant temperature gradient in the large vertical space, If the hot air in the upper part can be directly transferred to the occupied zone, it is beneficial to improve the temperature of the occupied zone, reduce the heat loss of the envelope, and offset the some heat loss from the cold air infiltration.Therefore, the heating need in the heating season is reduced.By analyzing the correlation about the vertical temperature distribution of the public area of the railway station, building the recycling procedure that pump the upper hot air directly to the occupied zone, the relationship between the temperature difference of the top area and the occupied zone and the maximum air flow rate of the heat recovery is established,and the optimal parameter is obtained. According to the summary of the spatial size of the railway station and the passengers, physical calculation model of a typical railway station is established. EnergyPlus is used to simulate the temperature distribution of the vertical space.Two methods of comparisons with the experiment, Fluent and EP mutual verification for verifying the accuracy of vertical space temperature distribution by the multi-regional model of EP are applied. After that,energy saving potential of the heat recovery mode is investigated and the feasibility of the heat recovery technology by reducing heating load-a,the actual energy saving rate- ?, the energy efficiency ratio -? and the investment payback period -(3 is evaluated.Based on the analysis of heat recovery operation conditions, when staff activities need to meet the heating thermal environment demand, and air temperature of the top is higher than air temperature of the staff activities, priority should be given to open heat recovery,then using the heating to ensure thermal environment requirements. Under the control principle, the energy saving rate based on the physical calculation model is calculated under different heat recovery control conditions for the typical station model. The energy saving rate of heat recovery varies with the change of heat recovery control conditions. Thus, The control parameters under the maximum energy saving rate to open heat recovery are obtained, "the temperature of personnel activity area is less than 18.5?, temperature difference between the top area and personnel activity area is greater than 1.5 ?2 ?, and the volume of heat recovery air is 15 ?20m3/s".According to heat recovery simulation calculation method using EP, the effects of factors such as climate area, orientation, height, window-wall ratio, skylight area and public area that have influence on energy saving are studied. The influences of those factors on the heat recovery are also obtained. In order to make energy-saving rate, energy efficiency ratio higher and have better value, the layout of building should be faced on the South East 30 degrees or west-east, window wall ratio is 0.4-0.5, the height and skylight area should increase appropriately under the design specification. Moreover, energy efficiency of heat recovery in public area is analyzed by orthogonal test method, the biggest impact is window-wall ratio, followed by height, orientation, skylight area, the smallest is the public area.