地鐵隧道畢業(yè)設(shè)計外文翻譯--釋壓通風(fēng)井影響下的活塞效應(yīng)通風(fēng)研究

1、中文 中文 5018 字 出處： 出處：Applied Thermal Engineering, 2008, 28(5): 372-379【原文】A study on underground tunnel ventilation for piston effects influenced by draught relief shaft in subway systemChi-Ji Lin, Yew Khoy Chuah, Chia-We

2、i LiuAbstractThis is a study on underground tunnel ventilation for piston effects influenced by draught relief shaft. Field measurements of transient air movement in the draught relief shaft for a typical Taipei underg

3、round subway station were taken under winter and summer conditions. It has been found that the air in the draught relief shaft has a maximum of 2 m/s, and on average lies between 0.7 and 1.1 m/s. This study defines an in

4、dex ηPE, forevaluating the efficiency of tunnel ventilation by piston effects. This index can be used toanalyze the piston effects due to different shaft length and sectional area. The measurement results show that the t

5、rain piston effects are effective only for certain shaft length and operating conditions.This study also used the authoritative SES computer program to simulate the piston effects. The simulation results for inflow and o

6、utflow velocity profile are almost consistent with the measurement. The shaft sectional area was also investigated and has been found that a larger sectional area resulted in larger volume flow rate, but the percentage i

7、ncrease is less than the percentage increase in the sectional area. This will result in smaller airvelocity in shaft and less effective air exchange between the tunnel and the outside ambient. It also has been found that

8、 length of the draught relief shaft is more so an important design parameter for efficient air exchange by piston effects for underground subway systems. Itis suggested here that the design of the draught relief shaft ha

9、s to consider requirements including ηPE, pressure loss and noise.Keywords: Draught relief shaft; Piston effect; Underground subway station; Tunnel ventilationm C ? AvVv ? Qb (1)AV QcFor air inflow,Av Cm ? KiC?p (2)A

10、C?psFor air outflow,Av Cm ? KoC?p ?1? C?Hi (3)A C?ps ? C?HcwhereA tunnel area (m2)Av relief shaft area (m2)Cm ratio of mass flow rate through relief shaft to mass flow rate through tunnelCΔp upstream relief shaft head

11、lossCΔps relief shaft head lossCΔHC coupling losses related to configuration of the interface between tunnel and relief shaftCΔHi entrance loss at the bottom of relief shaftKi, Ko empirical constants for inflow and outfl

12、owQb, Qc air flow volume rate through relief shaft and upstream(or downstream) (m3/s)V air velocity at tunnel (m/s)Vv air velocity at relief shaft (m/s)The space geometry of a modern subway station is typically complex.

13、The train operation is a prime factor for the piston effects. The train movement in tunnel is a highly transient air moving problem. The above equations are insufficient to analyze the transient air movement in the tunne