CRITERIAL NUMBER BY NATURALLY VENTILATED TUNNELS

All internal combustion engines produce exhaust gases containing noxio us compounds: carbon monoxide (CO), nitrogen oxides (NO,), carbon oxid es (CxHy) and smoke. With the help of a mathematical model the concent rations of some dangerous substances at the end of the tunnel were cal culated, and were replaced by a criterial number. A corresponding comp uter program was also developed thus enabling quick and simple calcula tions of some concentrations and the criterial number. Finally, a crit eria for the border between natural and forced ventilation is presente d as a correlation between the criterial number and other parameters. (C) 1998 Elsevier Science S.A. All rights reserved.