Ichiro Nakahori

A New Ventilation Control Method for the Mt. Ena Tunnel of Chuo Expressway

Abstract This paper describes a new ventilation control method for the Mt. Ena Tunnel(1) of Chuo Expressway in Japan, the second longest road tunnel (8.5 km) in the world. The whole tunnel is divided into four sections, each of which has four ventilation fans driven by variable speed thyristor motors. We study a predictive control strategy, based on a dynamic model of ventilation in the tunnel. Our control method aims to ventilate with minimum cost, while keeping pollutant concentrations of the carbon monoxide gas and the smoked gas under permission levels. The problem is formulated in a typical regulator problem with quadratic performance index. The on-line ventilation control is performed by using a computer. The results of simulations and field tests on the Mt. Ena Tunnel show that the proposed control system is more effective and less costly than the conventional ones.