| 摘要 |
The invention relates to a reciprocating engine which is used between a minimum rotation speed Nmin and a maximum speed Nmax, comprising a turbocharging unit (2) which is dimensioned such as to operate autonomously when: (i) supplying air to the intake manifold (8) of the engine via a coolant, (ii) being supplied with gas by the exhaust manifold (9, CR and CT) of the engine at the exhaust temperature, and (iii) the turbine supply pressure (P3) is essentially equal to the compressor discharge pressure (P2). In this way, at a constant air temperature and with fixed geometry, the turbcharging system supplies an essentially-constant volume of cooled air Vc when the pressure varies, and volume Vc is essentially proportional to the discharge section Sd offered to the hot gases. The invention is characterised in that the turbine pressure (P3) is maintained essentially equal to the compressor pressure (P2) by an EGR bypass (3) between the intake manifold (8) and the exhaust manifold (9), the latter being dimensioned such as to transfer the exhaust gas flow towards the intake manifold without any significant pressure drop. Moreover, the volume of cooled air Vc is smaller than the volume ingested by the engine at speed Nmax, such that a hot gas flow is reingested by the engine via the bypass (3) above speed Na, known as the compression adaptation speed, where the ingested volume is equal to Vc, and an air flow is diverted towards the turbine below speed Na. |
