| 摘要 |
For a fixed induction manifold air flow rate and an injection nozzle size, the opening time required by a cylinder inlet valve (40) is computed as a function of the pressure differential between the nozzle upstream fuel pressure, P1 and the induction manifold back-pressure, P2. An air flow controlled by a butterfly damper (30) in an induction manifold (18) is dosed with petrol via an injection nozzle (14), from a fuel pump (11) maintained at a set point pressure P1 =4 bar by pressure regulator (20). The back pressure , P2 then varies with the butterfly opening, alpha and the engine rotation speed ; its value can be computed from the air mass flow rate but is preferably measured directly by a sensor (34). |
