APPARATUSES AND METHODS FOR FUEL INJECTION AND/OR IGNITION IN AN INTERNAL COMBUSTION ENGINE
A shielded igniter includes a positive-ignition source surrounded by a shield defining a shielded space. The shield includes an inlet hole, a first outlet hole and a second outlet hole. The shielded igniter is disposed within a cylinder of an internal combustion engine adjacent a fuel injector such that a first fuel jet is directed towards the inlet hole such that fuel enters the inlet hole and forms an ignitable fuel-air mixture. The positive-ignition source ignites the fuel within the shielded space such that combustion products exit the first and second outlet holes on a trajectory tangential to a circumference axisymmetric with a longitudinal axis of the fuel injector. Combustion products emanating from the first and second outlet holes ignite respective second and third fuel jets adjacent the first fuel jet on opposite sides thereof.
1 . An apparatus for igniting fuel in an internal combustion engine system, said system having an internal combustion engine including a cylinder and a cylinder head, a fuel injector arranged in the cylinder head and including a nozzle disposed within the cylinder, the nozzle including a plurality of nozzle holes, the fuel injector configured to inject fuel through the plurality of nozzle holes into the cylinder in a plurality of fuel jets respectively, the apparatus comprising:
a shielded igniter including a positive-ignition source surrounded by a shield defining a shielded space therebetween, the shield including an inlet hole, a first outlet hole and a second outlet hole, the shielded igniter adapted to be disposed within the cylinder adjacent the fuel injector such that when the fuel injector is actuated to inject fuel through the plurality of nozzle holes into the cylinder, a first fuel jet in the plurality of fuel jets is directed towards the inlet hole;
whereby fuel from the first fuel jet enters the inlet hole and forms an ignitable fuel-air mixture within the shielded space;
the positive-ignition source ignites the ignitable fuel-air mixture within the shielded space such that combustion products from the ignited fuel-air mixture exit the first and second outlet holes
combustion products emanating from the first outlet hole ignite a second fuel jet in the plurality of fuel jets and combustion products emanating from the second outlet hole ignite a third fuel jet in the plurality of fuel jets; and
the second and third fuel jets are adjacent the first fuel jet on opposite sides thereof.
2 . The apparatus for igniting fuel as claimed in claim 1 , wherein the shielded igniter is adapted to couple to the fuel injector.
3 . The apparatus for igniting fuel as claimed in claim 1 , wherein the shielded igniter is adapted to couple to the engine.
4 . The apparatus for igniting fuel as claimed in claim 1 , wherein the first fuel jet is directed at the inlet hole.
5 . The apparatus for igniting fuel as claimed in claim 1 , wherein the first fuel jet is directed at an impingement point on an outer surface of the shielded igniter near the inlet hole.
6 . The apparatus for igniting fuel as claimed in claim 1 , wherein the combustion products emanating from the first and second outlet holes are on a trajectory tangential to a circumference axisymmetric with a longitudinal axis of the fuel injector.
7 . The apparatus for igniting fuel as claimed in claim 6 , wherein the circumference passes through the first outlet hole or the second outlet hole of the shielded igniter.
8 . The apparatus for igniting fuel as claimed in claim 6 , wherein the circumference passes through the first outlet hole and the second outlet hole of the shielded igniter.
9 . The apparatus for igniting fuel as claimed in claim 1 , wherein the circumference is axisymmetric with the cylinder.
10 . The apparatus for igniting fuel as claimed in claim 1 , wherein a trajectory of first and second outlet holes is along an azimuthal direction of the cylinder.
11 . The apparatus for igniting fuel as claimed in claim 1 , wherein combustion of the first, second and third fuel jets sequentially ignite and combust remaining fuel jets in the plurality of fuel jets.
12 . The apparatus for igniting fuel as claimed in claim 1 , wherein the fuel injector is actuated to inject fuel at an injection pressure above 200 bar.
13 . The apparatus for igniting fuel as claimed in claim 1 , wherein the fuel injector is actuated to inject fuel in a pilot injection event between 90 and 160 crank angle degrees before top dead center during a compression stroke.
14 . The apparatus for igniting fuel as claimed in claim 1 , wherein the fuel injector is actuated to inject fuel in a main injection event between 110 and 180 crank angle degrees before top dead center during a compression stroke.
15 . The apparatus for igniting fuel as claimed in claim 1 , wherein the fuel has an autoignition temperature above 350 degrees Celsius.
16 . The apparatus for igniting fuel as claimed in claim 1 , wherein the fuel is a gaseous fuel.
17 . The apparatus for igniting fuel as claimed in claim 1 , wherein the fuel is hydrogen, methane, propane, natural gas, ammonia, or mixtures thereof.
18 . The apparatus for igniting fuel as claimed in claim 1 , wherein the fuel is methanol, ethanol, propanol, butanol or blends thereof.
19 . The apparatus for igniting fuel as claimed in claim 1 , wherein the positive-ignition source is a heated surface.
20 . The apparatus for igniting fuel as claimed in claim 1 , wherein the positive-ignition source is a spark igniter.
21 . The apparatus for igniting fuel as claimed in claim 1 , wherein the positive-ignition source is a corona-discharge igniter.
22 . The apparatus for igniting fuel as claimed in claim 1 , wherein the positive-ignition source is an induction-heating igniter.