汽車空調(diào)外文翻譯--在汽車中熱化階段和冷卻階段的熱舒適性（英文）

1、ORIGINALO. Kaynakli Æ E. Pulat Æ M. KilicThermal comfort during heating and cooling periods in an automobileReceived: 9 September 2003 / Published online: 17 September 2004 ? Springer-Verlag 2004Abstract Most v

2、ehicles have a heating, ventilation and air conditioning (HVAC) device to control the thermal environments of interior of the vehicle. But, under hot summer season or cold winter conditions, it is difficult to achieve an

3、d maintain thermal comfort in an automobile from the start up to the steady-state conditions. During these transition periods, an understanding of human thermoregulatory processes facilitates the design and development o

4、f improved heating and cooling systems. This study presents a model of thermal interactions between a human body and the interior environment of an automobile. The model is based on the heat balance equation for human bo

5、dy, combined with empirical equations defining the sweat rate and mean skin tem- perature. Simulation has been performed by the use of transient conditions. The effects of both heating and cooling processes on the therma

6、l comfort inside the automobile are investigated. Results are compared with the present measurements and available experimental data in the literature. It is shown that the agreement between the experimental data and the

7、 model is very good.List of symbols A surface area, m2cp specific heat, J/(kg K) CSIG cold signal f correction factor h heat transfer coefficient, W/(m2 K) i segment number j air or fabric layers number k conductive heat

8、 transfer coefficient, W/(m K)L heat load, W/m2m body mass, kg _ m mass flow rate from per unit area, kg/(s m2) M metabolic heat production rate, W nl number of layers covering segment p water vapor pressure, kPa Q heat

9、transfer rate, W r outer radius of fabric layer R thermal or evaporative resistance, (m2 K)/W or (m2 kPa)/W S heat storage, W t time, s (unless specified in minutes) T temperature,?C TS thermal sensation V air velocity,

10、m/s w skin wettedness W humidity ratio, kgH2O/kg dry air _ W external work rate accomplished, W WSIG warm signal x thickness, mmGreek symbols a ratio of skin layer mass to total body mass g permeation efficiencySubscript

11、s a air al air layer b body bl blood cd conduction cl clothing cr core cv convection dif diffusion e exposed to convective and radiant environment ev evaporationO. Kaynakli Æ E. Pulat Æ M. Kilic (&) Faculty

12、 of Engineering and Architecture, Department of Mechanical Engineering, Uludag ? University, Gorukle Campus, 16059 Bursa, Turkey E-mail: mkilic@uludag.edu.tr Tel.: +90-224-4429183 Fax: +90-224-4428021Heat Mass Transfer (

13、2005) 41: 449–458 DOI 10.1007/s00231-004-0558-9Chakroun and Al-Fahed [7] presented a study of the temperature variation and thermal comfort inside a car parked in the sun during the summer months in Kuwait. They also con

14、sidered the effect of using dif- ferent combinations of internal covering on the tem- perature inside the car. Burch et al. [4] reported the results of a series tests on passenger thermal comfort during warm-up under sev

15、ere winter driving condi- tions. They found that low-power electric heating pads installed on the seat and back support greatly reduce the time needed to attain thermal comfort. Further reductions in warm-up time can be

16、achieved by installing electric heaters in the air ducts, although the power requirements associated with this method are substantial. In addition to their experimental study, they presented an analytical study on this s

17、ubject in the paper of Burch et al. [5]. Heating and cooling periods from the start up of the vehicle require some time to reach steady-state conditions. During these periods, conditions are highly nonuniform over the bo

18、dy of the occupant. The vehicle passenger experiences localized chilling due to contact with an initially cold seat or steering wheel, nonuniform radiant heat transfer with the surround- ings, localized solar irradiation

19、, and nonuniform air velocities that vary depending on the location of the air registers and dashboard control settings. Thus, in addition to the air temperature, several other factors have a bearing on the thermal comfo

20、rt of the pas- senger. Consequently, there is substantial interest in the development of more efficient techniques for achieving and maintaining passenger thermal comfort in an automotive environment. This study presents

21、 a model of thermal interactions between a human and the interior environment of an automobile. Since, segmental analysis permits the determination of local discomforts by considering the clothing insulation asymmetry ef

22、fects in the relatively small volumes such as automobile cabin, the present model is based on the heat balance equation for human body by dividing it into 16 segments. By combining Gagge et al.’s [10] and Olesen et al.’s

23、 [15] approaches, all body segments are considered as two-concentric cylinders and required new data such as surface areas of body segments and their masses are refined from the existing literature. In this way, apart fr

24、om the Gagge et al.’s [10] model, it is tried to determine the local discomforts by calculating the thermal interactions of each segment and the skin temperature and wettedness. Simulation has been performed by the use o

25、f transient conditions. The effects of both heating and cooling processes on the thermal comfort inside the automobile are investigated. Experiments were also conducted for cooling periods. Until the thermal comfort reac

26、hed in the automobile compartment, the temperature and the humidity changed dramatically. Driver and passengers are greatly affected by these changes. The simulation results and experimental data were compared, in order

27、to validate the present model.2 Mathematical modelThe velocity of conditioned air that flow over passenger is very important from comfort point of view in small compartments that have large heating and cooling capacity e

28、specially such as automobile cabin. Flowing air over driver and passengers injected by inlet vents has not same value on any occupant’s body. Although it is a good approximation to take average velocity for typical indoo

29、r conditions, this results important mistakes by considering automobile interior. Local air velocities on the body of sitting passenger were determined experi- mentally by Burch et al. [5] (Table 1). In this study, deter

30、mination of heat losses from various regions of passenger is based on these velocity values. The model used in this study is based on the same approach described in the study of Olesen et al. [15]. In this study, human b

31、ody is divided by 16 regions by considering clothing groups and local air velocities on the body in order to investigate the effects of thermal environment to occupants especially driver in detail for both winter and sum

32、mer condition. In Table 2, surface areas and their fractions of total body surface area are given. To compute temporal temperature variations by using stored energy in the body segments it is required the masses of these

33、 segments. The masses of body seg- ments and their fractions of the total body mass are shown in Table 3. By considering the human body as whole, mean skin temperature gives an idea from thermal comfort point of view but

34、 the temperatures of the extremities such as hand, foot and face or naked parts of human body may increase or decrease unwanted values. By using the developed model, time rate of changes of the parameters that affect the

35、 thermal comfort such as sensible and latent heat losses each of 16 regions, skin temperatures and skin wettedness may be examined.2.1 Thermal and physiological modeling of human bodyA two-compartment transient energy ba

36、lance model developed by Gagge et al. [10] represents the body as two concentric cylinders the inner cylinder represents theTable 1 Local air velocities on the body [5]Region Air velocity (m/s)Head 0.13 Trunk 0.11 Right