METHOD FOR DETERMINING THE DURATION FOR WHICH AN ORIFICE IS OPEN

摘要

The invention relates to a method for determining the duration (t2-t-i) for which an orifice (27) separating two spaces (28, 29) containing a fluid at different pressures is open. According to the invention, the pressure (P) in one of said spaces is measured as a function of time (t) and the variations in a characteristic stemming from the pressure measurement are determined, said opening time being determined on the basis of said variations in said characteristic, which may be the derivative or the acceleration of the pressure. The method is more particularly applicable to controlling the quantity of reducing agent, such as gaseous ammonia, injected into a catalytic system of the SCR type.