VENTILATION IN TUNNELS.

Extending the Principles of Impulse Ventilation in Tunnels to Apply to Smoke Control in Car Parks

In the past few years, there have been an increasing number of Impulse Systems installed in car parks, especially in Northern Europe. Unfortunately, no design method has been described openly in the public domain. This places Authorities Having Jurisdiction (AHJs, or Approving Authorities) in a difficult position when faced with a proposal. The present paper is intended to develop calculation p...

Analysis of the ventilation systems in the Dartford tunnels using a multi- scale modelling approach

The capabilities of the ventilation systems in the two road tunnels at Dartford (UK) are analysed using a multi-scale modelling approach. Both tunnels have complex semi-transverse ventilation systems with jet fans to control longitudinal flow. The construction and ventilation systems in the tunnels are described and the current emergency ventilation strategies are presented. The analysis includ...

Ventilation and Distance of Emergency Exits in Steep Bi-directional Tunnels

Experience from occurrences of fires in road tunnels shows that victims are usually found within a few hundred metres of the scene of the incident. The fatal consequences of a fire in a tunnel measuring only a few hundred metres can be comparable to those resulting from a fire in a long tunnel. In tunnels with considerable slope the hazard for tunnel users increases due to rapid smoke dispersio...

Tunnels in digital objects

An important concept in digital geometry for computer imagery is that of tunnel. In this paper we obtain a formula for the number of tunnels as a function of the number of the object vertices, pixels, holes, connected components, and 2 × 2 grid squares. It can be used to test for tunnel-freedom a digital object, in particular a digital curve.

Wireless Communication in Tunnels