Discussion on resistance calculation of urban comprehensiveutility tunnel ventilation systems

In this paper, through theoretical analysis methods, a frictional resistance calculation formula suitable for direct use by the ventilation designers of comprehensive utility tunnels is derived. Then, according to the characteristics of longitudinal ventilation of comprehensive utility tunnels, combined with relevant data, the value of the local resistance coefficient applicable to the ventilation system of comprehensive utility tunnels is given, which perfects the resistance calculation method of the urban comprehensive utility tunnel ventilation system. Finally, through calculation and analysis of a common 400 m ventilation section comprehensive utility tunnel example, it is found that the selection of fan wind pressure in many engineering practices is too large and should be appropriately reduced. This theoretical calculation method is also applicable to other single cabins and their combinations, and can provide a reference for similar engineering designs.