Dual fuel engine system having fuel-actuated unit pumps and method
AssigneeCaterpillar Inc.
InventorsHoisan Kim, Dana Ray Coldren, Lifeng Wang
Life of this patent
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Abstract
A dual fuel engine system includes an engine, and a fuel system including a pressurized fuel reservoir, a first fuel pump, and a plurality of second fuel pumps each having an actuating fluid inlet fluidly connected to at least one of the first fuel pump or the pressurized fuel reservoir. The plurality of second fuel pumps may intensify or de-intensify a pressure of a second fuel relative to a pressure of the first fuel used to actuate the second fuel pumps so as to obtain an increased flow rate of the second fuel. Related apparatus and methodology is also disclosed.
Claims20
A dual fuel engine system comprising:
- an engine including a plurality of cylinders formed therein;
- a fuel system including at least one fuel injector associated with each respective one of the plurality of cylinders, and each at least one fuel injector having a first fuel outlet set and a second fuel outlet set;
- the fuel system further including a pressurized fuel reservoir, a first fuel pump having a first fuel pump outlet fluidly connected to the pressurized fuel reservoir, and a plurality of high pressure first fuel conduits each extending from the pressurized fuel reservoir to one of the first fuel outlet sets;
- the fuel system further including a plurality of second fuel pumps each having a pumping element, an actuating fluid inlet for fluidly actuating the pumping element, and a second fuel pump outlet, a plurality of low pressure second fuel conduits each extending to one of the plurality of second fuel pumps, and a plurality of high pressure second fuel conduits each fluidly connecting one of the second fuel pump outlets to at least one of the respective second fuel outlet sets;
- and
- the actuating fluid inlet of each respective one of the plurality of second fuel pumps is fluidly connected to at least one of the first fuel pump outlet or the pressurized fuel reservoir.
A method of operating a dual fuel system comprising:
- feeding a pressurized first fuel from a first fuel pump to a pressurized fuel reservoir;
- feeding the pressurized first fuel to actuating fluid inlets of a plurality of second fuel pumps;
- actuating a pumping element of each respective one of the plurality of second fuel pumps via the pressurized first fuel to pressurize a second fuel;
- injecting the pressurized first fuel from a first fuel outlet set fluidly connected to the pressurized fuel reservoir into a cylinder in an engine;
- and
- injecting the pressurized second fuel from a second fuel outlet set fluidly connected to one of the plurality of second fuel pumps into the cylinder.
A dual fuel system comprising:
- a plurality of fuel injectors each including at least one of a first fuel outlet set and a second fuel outlet set, and a number of the plurality of fuel injectors is equal to a number of the first fuel outlet sets and a number of the second fuel outlet sets in the dual fuel system;
- a pressurized fuel reservoir;
- a first fuel pump having a first fuel pump outlet fluidly connected to the pressurized fuel reservoir, and a plurality of high pressure first fuel conduits each extending from the pressurized fuel reservoir to one of the first fuel outlet sets;
- a plurality of second fuel pumps each having an actuating fluid inlet and a second fuel pump outlet, a pumping element, a plurality of low pressure second fuel conduits each extending to one of the plurality of second fuel pumps, and a plurality of high pressure second fuel conduits each fluidly connecting one of the plurality of second fuel pump outlets to at least one of the respective second fuel outlet sets;
- and
- a plurality of actuating fluid conduits each extending from the first fuel pump or the pressurized fuel reservoir to the actuating fluid inlet of one of the plurality of second fuel pumps for fluidly actuating the respective pumping elements.
Dependencies are inferred from the claim text.