A study on applications of the natural ventilation pressure(NVP) in local tunnels

In spite of the importance of the natural ventilation pressure(NVP) in tunnels for the optimal design of the ventilation system, there have been only few studies on the NVP because its measurement and quantitative analysis are not straightforward. This study aims at quantifying the amount of the NVP with the terrain and meteorological data for the local major tunnels. And ultimately this will lead to developing the guidelines for quantifying and applying NVP for the optimal design of tunnel ventilation system. 22 local tunnels in the major routes are studied for the NVP quantification. NVP derived from the meteorological data is in the range of 20∼140 Pa, while NVP estimated from the terrain data ranges from 20 to 200 Pa. Since the jet fan pressure is about 10∼15 Pa per unit, the minimum level of NVP expected in the local tunnels is larger than the pressure rise by one unit of the ordinary jet fan. This implies that NVP in local tunnels should be quantified and be taken into consideration for the economic and safe ventilation design. The barometric pressure difference between tunnel portals is found to be the most influential factor, accounting for 61% of the NVP, while the wind pressure acting on the portals and the chimney effects occupy 22% and 17%, respectively.

keywords: 터널환기, 풍압, 기압장벽고, 굴뚝효과, 자연환기력, Tunnel ventilation, Wind pressure, Barometric barrier, Chimney effect, Natural ventilation pressure

Reference

1. Korea Expressway Corporation (2011), “Highway tunnel ventilation design criteria”, p 38-50.

2. Ministry of Land, Transport and Maritime Affairs in Korea (2011), “Road design manual (617. Ventilation)”, pp. 617-36-617-47.

3. Lee, C.W., Kim, S.H., Gil, S.W., Cho, W.C. (2009), “A case study for prediction of the natural ventilation force in a local long vehicle tunnel”, Journal of Korean Tunnelling and Underground Space Association, Vol. 11, No. 4, pp. 395-401.

4. Lee, C.W., Park, H.C. (2009), “A study on the natural ventilation force in tunnels”, Tunnel and Underground Space, Vol. 19, No. 3, pp. 226-235.

5. Kim, H.G., et al. (2012), “A study on the improvement of estimation guidelines of jet fans for smoke control in highway tunnel(Final report)”, Korea Expressway Corporation, pp. 142-202.

6. Roche, L. (1991), “Meteorological influence on tunnel ventilation: three new field experiment”, proceedings of 7th AVVT, pp. 513-544.

7. Maarsingh, R.A., Swart, L. (1991), “Wind-tunnel experiment on wind effect at tunnel portals”, proceedings of 7th AVVT, pp. 545-562.

8. Bettelini, M. (2009), “Managing the longitudinal air velocity in long road tunnels”, proceedings of 13th AVVT, pp. 53-68.

바로가기메뉴

Article Contents

Vol.16 No.3

A study on applications of the natural ventilation pressure(NVP) in local tunnels

Abstract

Reference

(사)한국터널지하공간학회