1. An internal combustion engine, comprising:
an engine block having at least one cylinder bore;
a cylinder head having a flame deck surface disposed at one end of the cylinder bore;
a piston connected to a rotatable crankshaft and configured to reciprocate within the cylinder bore, the piston having a piston crown portion facing the flame deck surface such that a combustion chamber is defined within the cylinder bore and between the piston crown and the flame deck surface;
a fuel injector having a nozzle tip disposed in fluid communication with the combustion chamber, the nozzle tip having at least one nozzle opening configured to inject a fuel jet into the combustion chamber and along a fuel jet centerline;
at least one duct defined in the combustion chamber between the piston crown and the flame deck surface, the at least one duct having a generally rectangular cross section and extending in a radial direction relative to the cylinder bore substantially along a segment of the fuel jet centerline.
2. The internal combustion engine of claim 1, wherein the at least one duct is at least partially defined by a pair of fins having an elongate shape that includes sidewalls extending substantially parallel to a centerline of the cylinder bore, and wherein the at least one duct is at least partially defined between two opposing sidewalls disposed to at least partially enclose the segment of the fuel jet centerline.
3. The internal combustion engine of claim 2, wherein at least one fin of the pair of fins is connected to the piston crown.
4. The internal combustion engine of claim 2, wherein at least one fin of the pair of fins is connected to at least one of the flame deck surface of the cylinder head, an intake valve, and an exhaust valve.
5. The internal combustion engine of claim 2, wherein two fins of the pair of fins are connected to one another to form a U-shaped insert that is connected to the piston crown.
6. The internal combustion engine of claim 5, wherein the piston crown portion further includes a piston bowl having a generally concave shape and wherein the at least one duct has an inlet and an outlet that are radially disposed within the piston bowl.
7. The internal combustion engine of claim 1, wherein the at least one duct is partially formed as a groove in the piston crown portion and at least partially formed between two walls extending parallel to one another around a portion of the fuel jet.
8. The internal combustion engine of claim 1, further comprising at least one recirculation inhibiting surface defined on a fin disposed between the piston crown and the flame deck surface, the fin having an elongate shape such that the at least one recirculation inhibiting surface is substantially parallel to a centerline of the cylinder bore and disposed between the at least one duct and an additional duct.
9. The internal combustion engine of claim 1, wherein a cross sectional area of an inlet of the at least one duct is between 3 and 10 times a cross sectional area of the fuel jet.
10. The internal combustion engine of claim 1, wherein a length of the at least one duct along the fuel jet centerline is between 1 and 8 times a minimum hydraulic diameter of an inlet cross section of the at least one duct.
11. The internal combustion engine of claim 1, wherein an inlet of the at least one duct is disposed at a radial distance from a centerline of the cylinder bore that is about 0.75 to 3 times a minimum hydraulic diameter of an inlet cross section of the at least one duct.
12. The internal combustion engine of claim 1, wherein a cross sectional area of the at least one duct increases in a radial direction away from a centerline of the cylinder bore at a rate of not more than 100% over a length of the at least one duct along the fuel jet centerline that is about equal to a hydraulic diameter of an inlet cross section of the at least one duct.
13. A ducted combustion system, comprising:
a combustion chamber defined in a machine;
a fuel injector configured to inject a fuel jet into the combustion chamber along a fuel jet centerline;
a duct having a generally rectangular cross section is defined within the combustion chamber and disposed to receive therein the fuel jet, the duct at least partially surrounding the fuel jet centerline.
14. The ducted combustion system of claim 13, wherein the duct is at least partially defined by a pair of fins having an elongate shape, each fin including a sidewall extending substantially parallel to the fuel jet centerline, and wherein the duct is at least partially defined between two opposing sidewalls disposed on each side of the fuel jet centerline.
15. The ducted combustion system of claim 13, wherein the duct is partially formed as a groove in a component, which is disposed around and at least partially defining the combustion chamber, and at least partially formed between two walls extending parallel to one another around the fuel jet centerline.
16. The ducted combustion system of claim 13, wherein a cross sectional area of an inlet of the duct is between 3 and 10 times a cross sectional area of the fuel jet where the fuel jet passes through the inlet, wherein a length of the duct along the fuel jet centerline is between 1 and 8 times a minimum hydraulic diameter of the inlet of the duct, wherein a cross sectional area of the duct increases in a direction along the fuel jet centerline at a rate of not more than 100% over a length of the duct along the fuel jet centerline that is about equal to a hydraulic diameter of an inlet of the duct.
17. A method for operating a combustion system, comprising:
injecting a fuel jet along a fuel jet centerline into a combustion chamber;
directing the fuel jet at least partially into a duct having a generally rectangular cross section such that local velocity gradients around the fuel jet create a substantially uniform mixture of fuel from the fuel jet with air present in the combustion chamber;
preventing entrainment of recirculated combustion products from a downstream region of the fuel jet to an upstream region of the fuel jet by substantially containing a segment of the fuel jet within the duct.
18. The method of claim 17, further comprising maintaining an equivalence ratio of about 2 at a flame lift-off length.
19. The method of claim 17, further comprising decelerating the recirculation of combustion products by creating velocity gradients in the combustion products that are induced by surfaces disposed between adjacent ducts.
20. A piston for use in an internal combustion engine, comprising:
a body portion connectable to a crankshaft of the engine, the body portion having a generally cylindrical shape defining a centerline;
a crown portion connected to the body portion;
at least one pair of elongate fins connected to the crown portion and extending away therefrom in a direction of the centerline, each fin of the at least one pair of elongate fins having a duct surface facing the other fin, the duct surface extending away from the centerline in a generally radial direction relative to the crown portion;
wherein a duct having a generally U-shaped cross section is defined on the crown portion of the piston between two facing duct surfaces of the at least one pair of fins and a bottom surface defined on the crown portion.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A mask pattern comprising:
a resist pattern; and
a gel layer on a surface of the resist pattern having a junction comprising hydrogen bonds between a proton donor polymer and a proton acceptor polymer, wherein the junction of the gel layer comprises:
a plurality of regions capable of undergoing hydrogen bonding, wherein the proton donor polymer and the proton acceptor polymer are hydrogen bonded therebetween; and
a defect region wherein the proton donor polymer and the proton acceptor polymer are not hydrogen-bonded therebetween so as to form a region lacking hydrogen bonding, between the hydrogen-bonded regions, the defect region of the gel layer forming a loop between the hydrogen bonded regions and the proton donor polymer of the defect region comprises a \u2014COOR group wherein R is a substituted or unsubstituted C1 to C20 hydrocarbon comprising silicon or a substituted or unsubstituted C1 to C20 acid-labile group comprising silicon, and
wherein the proton donor polymer comprises a first repeat unit comprising a maleic acid monomer unit according to the following formula:
wherein R3 and R4 are each independently hydrogen, a substituted or unsubstituted C1 to C20 hydrocarbon or a substituted or unsubstituted C1 to C20 acid-labile group.
2. The mask pattern of claim 1, wherein the gel layer is water insoluble.
3. The mask pattern of claim 1, wherein R is methyl, acetyl(isopropyl)(2-methyl-butan-3-on-2-yl), t-butyl, isonorbonyl, 2-methyl-2-adamantyl, 2-ethyl-2-adamantyl, 3-tetrahydrofuranyl, 3-oxocyclohexyl, \u03b3-butyllactone-3-yl, mavaloniclactone, \u03b3-butyrolactone-2-yl, 3-methyl-\u03b3-butyrolactone-3-yl, 2-tetrahydropyranyl, 2-tetrahydrofuranyl, 2,3-propylenecarbonate-1-yl, 1-methoxyethyl, 1-ethoxyethyl, 1-(2-methoxyethoxy)ethyl, 1-(2-acetoxyethoxy)ethyl, t-butoxycarbonylmethyl, methoxymethyl, ethoxymethyl, trimethoxysilyl or triethoxysilyl and further comprises silicon.
4. The mask pattern of claim 1, wherein the proton donor polymer further comprises a second repeat unit comprising at least one of an acrylamide monomer unit, a vinyl monomer unit, an alkyleneglycol monomer unit, an anhydrous maleic acid monomer unit, an ethyleneimine monomer unit, an oxazoline group-containing monomer unit, an acrylonitrile monomer unit, an allylamide monomer unit, a 3,4-dihydropyrane monomer unit or a 2,3-dihydrofuran monomer unit.
5. The mask pattern of claim 1, wherein the proton acceptor polymer comprises a first repeat unit comprising a monomer unit having an amido group.
6. The mask pattern of claim 5, wherein the proton acceptor polymer comprises a first repeat unit comprising a vinyl monomer unit according to the following formula:
wherein R5 is hydrogen or a methyl group;
R6 and R7 are each independently hydrogen or C1 to C5 alkyl, and R6 and R7 can be connected in the form of \u2014R6-R7 to form a cyclic structure.
7. The mask pattern of claim 6, wherein the proton acceptor polymer comprises a first repeat unit according to the following formula:
wherein n is an integer of 1 to 5.
8. The mask pattern of claim 7, wherein the proton acceptor polymer comprises a first repeat unit comprising a vinyl pyrrolidone monomer unit.
9. The mask pattern of claim 7, wherein the proton acceptor polymer comprises a first repeat unit comprising a vinyl caprolactam monomer unit.
10. The mask pattern of claim 1, wherein the gel layer further comprises a surfactant.
11. The mask pattern of claim 1, wherein the resist pattern comprises a material comprising a phenol-formaldehyde (Novolac) resin andor a diazonaphthoquinone (DNQ)-based compound.
12. The mask pattern of claim 1, wherein the resist pattern is formed using a chemically amplified resist composition comprising a photo-acid generator (PAG).
13. The mask pattern of claim 1, wherein the resist pattern is formed using a positive-type resist composition or a negative-type resist composition.
14. The mask pattern of claim 1, wherein the resist pattern is formed with a plurality of openings defining a hole pattern.
15. The mask pattern of claim 1, wherein the resist pattern is formed with a plurality of lines defining a line and space pattern.