Tunnel on the Metropolitan Expressway’s Yokohama Northwest Line

Location: Kita-Hassaku-cho, Midori-ku, Yokohama, Kanagawa Prefecture, etc.
Specifications and number of units: Φ2800mm horizontal axial flow fans: 4 units
Φ1250mm 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. 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.

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. 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.