| 摘要 |
The inventive supercharged engine comprises a bypass line (15) for ensuring a diverted air flow from a point (A) which is disposed downstream of a compressor (5) and provided with means (16) for cutting-off said derived airflow at a point (B) disposed between the upstream of an exhaust gas pipe (4) and a turbine disc (3). Variable geometry restriction means (19) is arranged on the exhaust gas intake unit upstream of the point (B), a turbocompessor is controlled by a wastegate valve (20) in such a way that the engine speed N0, at which the maximum supercharge value is obtainable, is substentially lesser than the speed Nmax of the maximum power and the rate of opening of restriction means (19) is selected in order to insert a sufficient difference between the exhaust gas pressure P3 and a pressure P3R upstream of the turbine disc in such a way that the pressure P3R remains substantially lower with respect to a supercharge pressure P2 in all cases when the derived air flow is desired in order to complement the exhaust gas flow when it is too low for producing the desired supercharge pressure P2 by increasing the exhaust gas pressure P3 as little as possible and to usefully recover the heat of a EGR gas or gases exhausted by the valve (20) in order to transfer or return said heat to the diverted airflow. |
