Tunnel on the Metropolitan Expressway’s Yokohama Northwest Line

Kita-Hassaku-cho, Midori-ku, Yokohama, Kanagawa Prefecture, and other locations
2800-mm diameter horizontal axial flow fans: 4 units;
1250-mm diameter jet fans: 32 units

The Northwest Route of the Yokohama Circular Route, which forms part of the road network of Yokohama, Kanagawa Prefecture, is a 7.1-km long road that connects the Yokohane Route on the coast and the Tomei Expressway inland. It includes a tunnel section that is approximately 4.1 kilometers long. By improving access to the Tokyo metropolitan area, this route improves logistics efficiency and helps to curb traffic congestion on local roads. Ventilation equipment has been installed in the tunnel section to improve the environment inside the tunnel, be considerate of the surrounding environment, and ensure safety in emergencies. This requires highly accurate ventilation control.

In the tunnel, air volume, wind speed, the concentration distribution of substances in the air, and pressure balance are constantly changing. EBARA has built a sophisticated ventilation control system that conducts repeated calculations based on these factors, achieving efficient operation of the individual ventilation systems to match the environment in the tunnel. In this way, we are contributing to the reduction of running costs. Because the Northwest Route is located in an urban area, in consideration of the surrounding environment, EBARA also supplied silencers to reduce the operating noise of the exhaust fans.