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1.
In the past, the temperature was used as the sole quota to control the indoor thermal environment in hot summer and cold winter areas of China, but a major quota, the relative air moisture, was often ignored. In this paper, the effect of relative air moisture on indoor thermal environment is analyzed. The results show that the energy consumption can be reduced and comfortable thermal environment can be provided under natural condition by regulating the indoor moisture.  相似文献   

2.
By using the building thermal environment simulation Toolkit DeST to simulation calculation of a residential building in Shanghai,the quantitative relationship between the factors of operation mode of air conditioning affecting the energy consumption of heating and air conditioning in residential buildings has been obtained in this paper,moreover,it has come to a conclusion that the tolerable temperature is superior to control temperature of air conditioning in respect of sensitivity and the living mode of indoor personnel has certain effect on the cold energy consumption.  相似文献   

3.
Ventilation design is the difficulty of transformer room design. Temperature field and velocity field in a transformer room was simulated by CFD method . By comparing simulation value with the experimental value in related document , the effectiveness of the mathematical model was verified. Based on it, an indoor substation transformer built was taken as the simulation object, then designed and simulated six kinds of ventilation condition by changing the location and area of air inlet, focused on the influence of air inlet on the ventilation effect by comparing the temperature field ,velocity field and temperature characteristic value in different condition. The simulation results show that when air inlet area is fixed, the air inlet should be arranged in the radiator side and its center height should be controlled in the radiator center height or slightly offset position, it should not be higher than the radiator. When the air inlet location is fixed, air inlet area should be increased along the high direction to improve ventilation effect. The conclusions can provide technical support for the ventilation design of transformer room.  相似文献   

4.
The internal shading can both impact on the sunshade and indoor daylighting, and work as an indoor heat source by absorbing heat. Presently the evaluation of overall energy efficiency of the internal shading is perceptual and qualitative. Therefore, the tests of the internal surface temperatures of house envelopes and the daylighting illuminance were carried out. It is shown that the surface temperature of interior walls with internal shading are 0.6℃～1℃ lower than those without; however,the surface temperature of internal shading is 3℃～5℃ higher than that of the interior walls. It can be seen that internal shading also forms an indoor heat source. The energy consumption of air-conditioning with internal shading decreases by 17.24% than that without, which indicates the internal shading can certainly reduce the indoor air conditioning load; however, the daylighting illuminance declines by 81%, with the results that the artificial lighting energy consumption is 1.88 times as much as that without the internal shading.  相似文献   

5.
For the most common fresh air handling way supplying fresh air directly into the rooms after it has been handled in fan coil with outdoor air systems, the paper gives the design method of i d pattern in winter air conditioning operating mode, which determines the state of supply air of fan coil units and the final parameter of winter fresh air througn the ratio of fresh air. For selecting the final parameter of fresh air after it has been handled,the authors gives three conditions:Winter fresh air is handled to room enthalpy;Winter fresh air is handled between room enthalpy line and room temperature line; Winter fresh air is handled to room temperature or a little lower than room temperature. The comparing result show that the second method is desirable after comparison.  相似文献   

6.
Taking residential buildings as the study objects, for three different residential load types such as low load, medium load, and high load type, indoor thermal environments of different load sharing-rates are simulated, respectively. Indoor thermal comfort and indoor air quality of different load sharing-rates are also analyzed and evaluated. And the appropriate range of cooling load sharing-rates are given from the view of both occupants thermal comfort and occupants health. When ωc (the sensible heat load sharing rate of the radiant terminal device) <0.7, the human thermal index in work region can be controlled within the range of thermal comfort standard. From the point of avoiding local discomfort, ωc is suggested to take 04~1. As regard to indoor air quality, for the constant air volume mode, ωc is suggested to take 0.5~0.9 under low and middle load conditions, and ωc is suggested to take 0.35~0.6 under high load conditions. For the variable air volume mode, the smaller the value of ωc is, the better indoor air quality is.  相似文献   

7.
Based on the definitions of air conditioning period, dehumidifying period and heating period, this paper puts forward the exchanging conditions and psychrometric process of ventilation system in residences. Because of the remarkable humid climate in hot summer and cold winter regions, the ventilation dehumidification becomes a more important part of the air treatment system. In order to improve the indoor thermal environment quality, new strategies must be founded to control both temperature and humidity of ventilation system.  相似文献   

8.
To obtain the influence of outer environmental condition on the indoor airflow distribution for the 25T air-conditioned train in Qinghai-Tibet, the Realizable k-ε model is adopted to numerically analyze the indoor temperature and velocity fields of the running train. The results indicate that solar radiation has great effect on the indoor temperature field and it is meaningful for improving the thermal comfort to adjust the air supply parameters with the outer environmental condition. Under different air supply conditions, it is the conjugating relation between the indoor temperature field and velocity field that leads to different thermal comfort in different regions of the running train. In addition, the operating modes exchange under different outdoor environmental conditions is also discussed and some additional functions of the using air-conditioning system are put forward too.  相似文献   

9.
The field test and questionnaire survey were carried out in the departure lounge at the railway stations in Changsha and Shanghai which were typical cities in hot summer and cold winter zone. Thermal sense vote (TSV), thermal neutral temperature and acceptable temperature range were studied. It was shown that the response of passengers to thermal environment was different. The thermal neutral temperature was 27 ℃ and acceptable temperature range was 23.8~30.2 ℃.The passengers' TSV did not keep at the initial value. Instead, it increased with the increase of waiting time and the growing rate depended on the difference of indoor outdoor temperature.  相似文献   

10.
The vertical U-tube ground-coupled heat pump system provides cold and heat for the controlling of indoor environment. Under the air-conditioning condition, the vertical U-tube ground-coupled heat pump system with heat recovery can provide domestic hot water. The influence of supplying domestic hot water on the heat transfer performance of ground heat exchangers is different under different operating modes in summer and winter. Through a project design of ground-source heat pump system, the influence of supplying domestic hot water under heat storage mode on the heat transfer performance of ground heat exchangers in summer and winter is respectively analyzed. The dynamic performance of heat exchangers under different working conditions is analyzed, and through numerical calculation, the heat transfer performance parameters of ground heat exchangers under different operating modes are obtained. From the calculation results, the adjusting methods based on the load characteristics of this project represent.  相似文献   

11.
The structure and energy conservation characteristics of hybrid desiccant cooling system with condensation heat recovery are introduced briefly. Based on the first and second law of thermodynamics, a system thermodynamic model is established and the solution process given in a diagram. The dehumidification capacity is calculated under different exergy efficiency and indoor sensible heat conditions. The calculation results show that the desiccant wheel barely can compensate for the humidity load of outdoor air under with a ventilation rate of providing fresh air once per hour; when the fresh air rate of ventilation is limited to 0.5 times per hour, however, the desiccant wheel possess sufficient capacity under relatively large wheel exergy efficiency and high sensible heat load.  相似文献   

12.
The heating and air conditioning energy consumption of residential buildings is influenced by the behavior of indoor living personnel.On the basis of research and analysis,two kinds of calculation modes reflecting the behavior of indoor living personnel are estimated.Under two kinds of different calculation modes,by using the building thermal environment simulation Toolkit DeST to simulate the energy consumption calculation for certain residential building in Shanghai,and the simulation results are compared with the research results.The influence of calculation mode on heating and air conditioning energy consumption of residential buildings in Shanghai is analyzed in this paper.In order to obtain the right simulation calculation method correctly reflecting the energy consumption of residential buildings.This method can be used for analysis and evaluation of heating and air conditioning energy consumption of residential buildings in Shanghai,and it can serve as instruction for right energy design of residence building.  相似文献   

13.
In order to establish “Evaluation Standard for indoor thermal environment of civil buildings”,acceptable temperature range of indoor environment without air conditioning and heating in hot summer and cold winter zone is indispensable.A two-year field measurement and questionnaire survey were carried on from 2007 to 2009 in Chongqing,which focused on office buildings and residential buildings.After the analysis of indoor and outdoor environment,occupants evaluation and thermal adaptability,a method to obtain the acceptable temperature range,was proposed.Regressing data by temperature range,and combined with human physiological and psychological experiments,the acceptable temperature range of environment without air conditioning and heating in Chongqing was determined according to outdoor air temperature changes in one year.A Comparation of methods to determine the acceptable temperature range in some international standards was discussed.  相似文献   

14.
A physiological and psychological experiment was conducted in summer, 2008 to ascertain the effect of air flow on human thermal comfort in hot summer. The statistics analysis shows that air flow makes physiological index and thermal sensation an obvious drop tendency, which is correlated to the air temperature of indoor environment. The lower the air temperature is, the greater the physiological index and the thermal comfort drop. But when the temperature is up to about 34℃, the air flow almost does not make any change to physiological index while the human sensation is still improved. These results indicate that air flow can improve human thermal comfort to some extent, but the improvement has limits. Higher air temperature, strong wind and long time exposure to wind can lead to uncomfortableness.  相似文献   

15.
Three typical commercial buildings in Chongqing, P.R. China were selected to study the actual summertime operation and energy situations of heating ventilating and air conditioning (HVAC) systems in commercial buildings. Based on tests of energy consumption of HVAC systems in these three buildings, we analyzed the electricity consumption of the main components of the air conditioning systems. The energy efficiency of the chillers and air conditioning water distribution systems were studied. The indoor thermal environment in these three buildings were also tested and discussed. It is concluded that problems exist in the air conditioning systems of commercial buildings. Among the problems are over sized system design, low equipment operating efficiencies, poor operation management, and lack of indoor temperature controls. To reduce energy consumption of HVAC systems in commercial buildings, we propose energy efficient strategies such as sizing systems based on accurate load calculation and automatic control under partial load conditions.  相似文献   

16.
According to the characteristics of the climate and distribution of solar resource in Chongqing, the technology idea of integrated application of solar energy and building is proposed, which is suitable for Chongqing area, i.e. solar assisted indoor ventilation cooling measure, which takes full advantage of the strong solar radiation in summer and strengthens the “chimney effect” to promote natural ventilation inside the building, improve the summer indoor hot and humidity environment, save energy and achieve solar energy passive using. Experiments and analysis show that the 0.16~0.22 m/s indoor air speeds are produced by the thermal effect of solar energy, which is increased by 14%~40%. And the average indoor temperature is 2.6~3.4 ℃ lower than the outdoor average temperature, and the indoor thermal comfortable state is effectively improved.  相似文献   

17.
A sving energy system can get natural ventilation in the storied healthy build-ings with air condition or heating. The principal component of this system is an efficient heat ex-changer made of a set of heat pipes. This system can be operated between two sides of one floor slabto change the energy carried both by the hot air flow and the cold air flow, This svstem can make aspossibly keeping indoor air fresh with a little energy air loss only. It is possible for using this systemto cure a sick building into a healthy building. This system can be put dperation between both thepipes of waste air flow and fresh air flow for an integrated air conditional svstem with fresh air.  相似文献   

18.
This paper describes the annual energy consumption and economic assessment of air-source heat pump(ASHP) and ground-source heat pump(GSHP),based on hourly building load of typical house in Fuzhou.Analysis results show that the energy consumption of GSHP is 15% less than that of ASHP through all year,where there is 13% less in summer and 20% less in winter.Although the seasonal energy efficiency ratio of GSHP in Fuzhou is higher than that of ASHP,it has no obvious effect on the energy efficiency as it is in the hot summer and cold winter zone.In comparison with ASHP,the GSHP is not cost-effective.  相似文献   

19.
Anchorage zone on tower of cable stayed bridge has complex structures and stress distributions, and keeping it on a safety state under a large tonnage tension and prestress is more concerned in design and construction. The stress distribution of the anchorage zone was analyzed by 3D finite element method. Furthermore, the mechanical properties and the rules of stress distributions were investigated and compared in three different load cases. The results show that the disposition form of level prestressing tendon is reasonable. The stress of the entire tendon is very close to 1 116 MPa under the tension control stress of 1 260 MPa. It is shown that the intensity of the tendon has given full play to prestress and it is not appropriate to increase the tension control stress.  相似文献   

20.
The high grade gray water was pre treated by biologic contact oxidation on load of 0.72 KgBOD5·m-3·d-1, and then post treated by constructed wetland. On the basis of experiment, it was found that: Totle nitrogen (TN) was the restrictive index of the combinational technique. To meet the reclaimed water quality standard and reuse for waterscape, the peak hydraulic load of constructed wetland was 0.50 m·d-1 in summer (30~36 ℃), and 0.33 m·d-1 in winter (8~12 ℃). And the load ratio of the peak hydraulic under the summer and winter conditions was 3:2. With the experimental results and reclaimed water quantity requirements in different seasons of buildings, treatment scale can be determined.  相似文献   

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