Predicting Permissible CO Concentration Limit for Longitudinal Ventilation Tunnels under Normal Case

Abstract:

The current Chinese code Specifications for design of ventilation and lighting in highway tunnel lists the admissible CO mass concentration limits for tunnel and varies from international standards on both values and principles. Two typical types of longitudinal ventilation tunnel are longitudinal ventilation tunnel with jet fan(s) and longitudinal ventilation tunnel with jet fan(s) and vertical shaft(s). Difference form of Coburn-Forster-Kane equation (CFK equation) was introduced to calculate the CO mass concentration limits for those two types of longitudinal ventilation tunnel and a fitting equation for predicting permissible CO mass concentration limits is presented and is applicabe to both types of tunnel. The results show that the CO mass concentration limit values for long length longitudinal ventilation tunnel should be lower.

Key words:longitudinal ventilation tunnel, jet fan, vertical shaft, CO mass concentration limit, CFK equation