A compression-ignition "split-cycle" engine comprises: a cylinder block with an expansion cylinder having an expansion piston that is adapted to move alternatively between a top dead center (ETDC) and a bottom dead center (EBDC) by a crankshaft mechanism that causes a predetermined position of the expansion piston to correspond to a predetermined crankshaft angle; a compression cylinder having a compression piston that is adapted to move alternatively between a top dead center (CTDC) and a bottom dead center (CBDC) according to a predetermined angular phase shift in delay to the expansion piston; a cylinder head that closes the cylinders and comprises a crossover passageway with an opening in constant communication towards compression cylinder and an opening having a transfer valve towards expansion cylinder, an intake valve and a exhaust valve; a means for opening/closing the transfer valve; a means for opening/closing exhaust valve at predetermined moments of the alternative cycle of the pistons, and a fuel injector in the crossover passageway. The opening movement of the transfer valve is carried out in advance 20° or more of crankshaft angle with respect to the crankshaft angle of the ETDC, such that from the opening instant up to reaching the ETDC there is a substantial equalization of pressure between the cylinders, such that between the ETDC and the CTDC a transfer occurs of the comburent fluid between the two cylinders, and such that injector injects the fuel starting from the achievement of the ETDC.
Split-Cycle Engine
GENTILI, ROBERTO;MUSU, ETTORE;ROSSI, RICCARDO
2010-01-01
Abstract
A compression-ignition "split-cycle" engine comprises: a cylinder block with an expansion cylinder having an expansion piston that is adapted to move alternatively between a top dead center (ETDC) and a bottom dead center (EBDC) by a crankshaft mechanism that causes a predetermined position of the expansion piston to correspond to a predetermined crankshaft angle; a compression cylinder having a compression piston that is adapted to move alternatively between a top dead center (CTDC) and a bottom dead center (CBDC) according to a predetermined angular phase shift in delay to the expansion piston; a cylinder head that closes the cylinders and comprises a crossover passageway with an opening in constant communication towards compression cylinder and an opening having a transfer valve towards expansion cylinder, an intake valve and a exhaust valve; a means for opening/closing the transfer valve; a means for opening/closing exhaust valve at predetermined moments of the alternative cycle of the pistons, and a fuel injector in the crossover passageway. The opening movement of the transfer valve is carried out in advance 20° or more of crankshaft angle with respect to the crankshaft angle of the ETDC, such that from the opening instant up to reaching the ETDC there is a substantial equalization of pressure between the cylinders, such that between the ETDC and the CTDC a transfer occurs of the comburent fluid between the two cylinders, and such that injector injects the fuel starting from the achievement of the ETDC.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.