US Patent 9903284 Dual-fuel engine system and method having the same

Dual-fuel engine system includes cylinders in which the cylinders have an intake valve and an exhaust valve that control a flow of fluid into and out of a combustion chamber of the corresponding cylinder. The intake valve is configured to have an intake valve closure (IVC) timing. The dual-fuel engine system is configured to operate in a single-fuel mode and a dual-fuel mode. The combustion chamber and a piston are designed to provide a compression ratio. The dual-fuel engine system also includes one or more processors that are operably coupled to and configured to control operation of the first fuel injector. The compression ratio and the IVC timing are selected to achieve a target pre-combustion temperature. The target pre-combustion temperature permits the dual-fuel engine system to operate at a high substitution rate in the dual-fuel mode and at a sufficient fuel efficiency in the single-fuel mode.