Piston engine with means for variably restricting intake-port flow

Claim 1

A piston type engine for achieving stable and rapid dilute combustion to produce very low NO output, wherein the engine includes a variable restriction air controlling means called air throttle, fuel input means, intake volume called intake manifold fluidly connected between said air throttle and an intake port in the engine head, said head being mounted on a cylinder block including a cylindrical passage in which a piston reciprocates, so that the geometrical combination of said head and said cylinder and said piston form a volume of cyclicly varying displacement called combustion chamber, said intake porting being connected to the combustion chamber, intake valve means opening and closing fluid connec- . tion between said intake port and the combustion chamber in phase relation to the piston reciprocations to control flow from the intake port to the combustion chamber, exhaust valve means fluidly connecting the combustion chamber to an exhaust passage and opening and closing in specific phase relation to piston reciprocation, ignition means for the combustion chamber firing in phase to piston reciprocation, said engine operating on the four cycle principle comprising an intake stroke, a compression stroke, a power stroke and an exhaust stroke;" means for variably restricting flow in the intake port to produce high velocity intake flow structured as "Coanda" flow in the intake port, that portion of the intake port between the means for variably restricting flow in the intake port and the intake valve being shaped to preserve the flow energy of said "Coanda" wall attached flow whereby the in-port "Coanda" flow, flow pattern one, passes by the intake valve into the combustion chamber in a structured three dimensional flow, flow pattern two, where said flow pattern two is arranged so that in interaction with said combustion chamber surfaces flow pattern two induces and forms a three dimensional in-cylinder flow pattern, flow pattern three, said in-cylinder flow pattern three having velocity gradients such that any fluid element located outside of combustion chamber boundary layers is by the end of the compression stroke stretched, distorted and spread within the combustion chamber volume so that said fluid element is widely distributed spatially over said combustion chamber volume prior to ignition time, so that the concentration gradients within the interior of said combustion chamber volume are greatly increased by said structured flow causing great increase in the speed and completeness of mixing for a set turbulence level within the combustion chamber volume to produce very tight air-fuel-residual microscale mixing statistics in the combustion chamber by ignition firing time, wherein the variable restriction is adjusted with sufficient flow restriction so that a sufficient flow kinetic energy is" delivered "from said port passage into said cylinder so that the three dimensional in-cylinder flow pattern, as it interacts with said variable volume combustion chamber, flows so that the interaction of the initial flow energy pattern and the turbulent flow energy decay rates leaves sufficient turbulence levels in the cylinder at combustion time to produce an adequately high turbulent to laminar flame speed ratio so as to produce adequately fast combustion with the dilute mixture in said combustion chamber, control means for the throttle opening, variable restriction and fuel input means, so that for the rotation speed, intake manifold volume displacement, and inlet and outlet valve timing for said engine, the masses of fuel, air and products of combustion in the cylinder during the compression stroke form ratios and gross concentrations such that when mixed, a lean combustible mixture is formed having sufficient dilution so as to produce a low enough peak combustion temperature.so that-NO formation is very small.

Claim 17

A method for achieving stable and rapid dilute combustion to produce very low NO output in a piston type engine, wherein the engine includes a variable restriction air controlling means called air throttle, fuel input means, intake volume called intake manifold fluidly connected between said air throttle and an intake port in the engine head, said head being mounted on a cylinder block including a cylindrical passage in which a piston reciprocates, so that the geometrical combination of said head and said cylinder and said piston from a volume of cyclicly varying displacement called combustion chamber, said intake porting being connected to the combustion chamber, intake valve means opening and closing fluid connection between said intake port and the combustion chamber in phase relation to the piston reciprocations to control flow from the intake port to the combustion chamber, exhaust valve means fluidly connecting the combustion chamber to an exhaust passage and opening and closing in specific phase relation to piston reciprocation, ignition means for the combustion chamber firing in phase to piston reciprocation, said engine operating on the four cycle principle comprising an intake stroke, a compression stroke, a power stroke and an exhaust stroke; said method comprising the steps of: (1) Producing a dilute combustible air-fuel mixture; (2) Introducing said mixture into the combustion chamber; " (3) Producing a structured three-dimensional inducted flow of said mixture inside said combustion chamber during the intake stroke; (4) Variably controlling the flow kinetic energy and flow pattern of said three-dimensional inducted flow, thereby producing in the combustion chamber a high velocity gradient structured turbulent flow having sufficient coherence on large and intermediate scales to produce very tight microscale air-fuel-residual statistics and high turbulent to laminar flame speed ratios for efficient controlled dilute combustion.

Claim 18

A method for achieving stable and rapid dilute combustion to produce very low NO output in a piston type engine, wherein the engine includes a variable restriction air controlling means called air throttle, fuel input means, intake volume called intake manifold fluidly connected between said air throttle and an intake port in the engine head, said head being mounted on a cylinder block including a cylindrical passage in which a piston reciprocates, so that the geometrical combination of said head and said cylinder and said piston from a volume of cyclicly varying displacement called combustion chamber, said intake porting being connected to the combustion chamber, intake valve means opening and closing fluid connection between said intake port and the combustion chamber in phase relation to the piston reciprocations to control flow from the intake port to the combustion chamber, exhaust valve means fluidly connecting the combustion chamber to an exhaust passage and opening and closing in specific phase relation to piston reciprocation, ignition means for the combustion chamber firing in phase to piston reciprocation, said engine operating on the four cycle principle comprising an intake stroke, a compression stroke, a power stroke and an exhaust stroke; said method comprising the steps of: (1) Producing a dilute combustible air-fuel mixture; (2) Introducing said mixture into the combustion chamber; " (3) Producing a structured three-dimensional inducted flow of said mixture inside said combustion chamber during the intake stroke; (4) Variably controlling the flow kinetic energy and flow pattern of said three-dimensional inducted flow, thereby producing in the combustion chamber a high velocity gradient structured turbulent flow having sufficient coherence on large and intermediate scales to produce very tight microscale air-fuel-residual statistics and high turbulent to laminar flame speed ratios for efficient controlled dilute combustion.

Claim 19

A method for achieving stable and rapid dilute combustion to produce very low NO output in a multicylinder piston type engine, wherein the engine includes a variable restriction air controlling means called air throttle, fuel input means, intake volume called intake manifold fluidly connected between said air throttle and the intake ports in th l engine head arrangement, said head arrangement being mounted or a cylinder block including multicylindrical passages in each o: which a piston reciprocates, so that the geometrical combinatit of said head arrangement and said cylinders and said pistons form volumes of cyclicly varying displacement each of which is called a combustion chamber, at least one intake port being connected.to each combustion chamber, intake valve means openii and closing fluid connection between said intake port and the corresponding combustion chamber in phase relation to the piston reciprocations in said combustion chamber to control flow from the intake port to the combustion chamber, exhaust valve means fluidly connecting each said combustion chamber to an exhaust passage said exhaust means opening and closing in specific phase relation to piston reciprocation, ignition means for each combustion chamber firing in phase to piston reciprocation in that combustion chamber's cylinder, each cylinder of said engine operating on the four cycle principle comprisinc an intake stroke, a compression stroke, a power stroke and an exahust stroke; said method comprising the steps: (1) Producing and delivering a dilute combustible air-fuel mixture to each cylinder whereby under steady-state operating conditions substantially identical air-fuel ratios and substantially identical air-fuel mixture mass flows are delivered to each intake port, (2) Controlling the flow of products of previous combustion so that the mass of said products of previous combustion at the end of the intake stroke under steady-state operating conditions is substantially identical in each cylinder and from cycle to cycle in each cylinder, (3) For each cylinder: (a) introducing said air-fuel mixture into each combustion chamber, (b) producing a structured three-dimensional inducted flow of said mixture inside said combustion chamber during the intake stroke, and (c) variably controlling the flow kinetic energy and flow pattern of said three-dimensional inducted flow, thereby producing in each combustion chamber a high velocity gradient structured turbulent flow having sufficient coherence on large and intermediate scales to produce very tight microscale air-fuel-products of previous combustion statistics and high turbulent to laminar flame speed ratios for efficient controlled dilute combustion.

Claim 20

A method for achieving stable and rapid dilute combustion to produce very low NO output in a multicylinder piston type engine, wherein the engine includes a variable restriction air controlling means called air throttle, fuel input means, intake volume called intake manifold fluidly connected between said air throttle and the intake ports in th l engine head arrangement, said head arrangement being mounted or a cylinder block including multicylindrical passages in each o: which a piston reciprocates, so that the geometrical combinatit of said head arrangement and said cylinders and said pistons form volumes of cyclicly varying displacement each of which is called a combustion chamber, at least one intake port being connected.to each combustion chamber, intake valve means openii and closing fluid connection between said intake port and the corresponding combustion chamber in phase relation to the piston reciprocations in said combustion chamber to control flow from the intake port to the combustion chamber, exhaust valve means fluidly connecting each said combustion chamber to an exhaust passage said exhaust means opening and closing in specific phase relation to piston reciprocation, ignition means for each combustion chamber firing in phase to piston reciprocation in that combustion chamber's cylinder, each cylinder of said engine operating on the four cycle principle comprisinc an intake stroke, a compression stroke, a power stroke and an exahust stroke; said method comprising the steps: (1) Producing and delivering a dilute combustible air-fuel mixture to each cylinder whereby under steady-state operating conditions substantially identical air-fuel ratios and substantially identical air-fuel mixture mass flows are delivered to each intake port, (2) Controlling the flow of products of previous combustion so that the mass of said products of previous combustion at the end of the intake stroke under steady-state operating conditions is substantially identical in each cylinder and from cycle to cycle in each cylinder, (3) For each cylinder: (a) introducing said air-fuel mixture into each combustion chamber, (b) producing a structured three-dimensional inducted flow of said mixture inside said combustion chamber during the intake stroke, and (c) variably controlling the flow kinetic energy and flow pattern of said three-dimensional inducted flow, thereby producing in each combustion chamber a high velocity gradient structured turbulent flow having sufficient coherence on large and intermediate scales to produce very tight microscale air-fuel-products of previous combustion statistics and high turbulent to laminar flame speed ratios for efficient controlled dilute combustion.

Claim 21

A method for achieving stable and rapid dilute combustion to produce very low NO output in a multicylinder piston type engine, wherein the engine includes a variable restriction air controlling means called air throttle, fuel input means, intake volume called intake manifold fluidly connected between said air throttle and the intake ports in the engine head arrangement, said head arrangement being mounted on a cylinder block including multicylindrical passages in each of which a piston reciprocates, so that the geometrical combination of said head arrangement and said cylinders and said.pistons form volumes of cyclicly varying displacement each of which is called a combustion chamber, at least one intake port being connected to each combustion chamber, intake valve means opening and closing fluid connection between said intake port and the corresponding combustion chamber in phase relation to the piston reciprocations in the said combustion chamber to control flow from the intake port to the combustion chamber, exhaust valve means fluidly connecting each said combustion chamber to an exhaust passage said exhaust means opening and closing in specific phase relation to piston reciprocation, ignition means for each combustion chamber firing in phase to piston reciprocat: in that combustion chamber's cylinder, each cylinder-of said engine operating on the four cycle principle comprising an intake stroke, a compression stroke, a power stroke and an exhau: stroke; said mixture of fuel, air, and products of combustion composed of the fuel, the fraction of the air having the chemically correct mass of oxygen to completely burn the fuel, the air in excess of said chemically correct mass of air, called excess air, and the products of combustion wherein said excess air in combination with said products of combustion is called diluent, and where the diluent thermal capacitance is defined as the product of the mass average specific heat at constant pressure of the diluent times the mass of the diluent present in the combustion chamber and cylinder of the engine at the end of the intake stroke and where the chemical condition of "incipient misfire" can be defined by testing as follows: for a homogeneously mixed composition of air, fuel, and products of combustion at each pressure and temperature condition corresponding to ignition time in said cylinder for a specified fuel mass and air-fuel ratio, increase products of combustion concentration until misfire would occur in 15% of the ignition events, said method comprising the steps of: (1) Producing and delivering a dilute combustible air-fuel mixture to each cylinder whereby under steady-state operating conditions substantially identical air-fuel ratios and substantially identical air-fuel mixture mass flows are delivered to each intake port, (2) Controlling the flow of products of previous combustion so that the mass of said products of previous combustion at the end of the intake stroke under steady-state operating conditions is substantially identical in each cylinder and from cycle to cycle in each cylinder, under steady-state engine operating conditions, (3) Controlling the masses of air, fuel, and product of combustion present at the end of the intake stroke for each of said cylinders so that the mass of diluent in the cylinder is more than 80% of the diluent producing incipient misfire und engine operating loads which would produce significant NO X emissions for a conveniently operated engine, (4) For each cylinder: (a) introducing the mixture of step 3 into each combustion chamber, (b) producing a structured three-dimensional inducted flow of said mixture inside said combustion chamber during the intake stroke, and (c) variably controlling the flow kinetic energy and flow pattern of said three-dimensional inducted flow, thereby producing in each combustion chamber a high velocity gradient structured turbulent flow having sufficient coherence on large and intermediate scales to produce very tight microscale air-fuel-products of previous combustion statistics and high turbulent to laminar flame speed ratios for efficient controlled dilute combustion.

Claim 22

A method for achieving stable and rapid dilute combustion to produce very low NO output in a multicylinder piston type engine, wherein the engine includes a variable restriction air controlling means called air throttle, fuel input means, intake volume called intake manifold fluidly connected between said air throttle and the intake ports in the engine head arrangement, said head arrangement being mounted on a cylinder block including multicylindrical passages in each of which a piston reciprocates, so that the geometrical combination of said head arrangement and said cylinders and said.pistons form volumes of cyclicly varying displacement each of which is called a combustion chamber, at least one intake port being connected to each combustion chamber, intake valve means opening and closing fluid connection between said intake port and the corresponding combustion chamber in phase relation to the piston reciprocations in the said combustion chamber to control flow from the intake port to the combustion chamber, exhaust valve means fluidly connecting each said combustion chamber to an exhaust passage said exhaust means opening and closing in specific phase relation to piston reciprocation, ignition means for each combustion chamber firing in phase to piston reciprocat: in that combustion chamber's cylinder, each cylinder-of said engine operating on the four cycle principle comprising an intake stroke, a compression stroke, a power stroke and an exhau: stroke; said mixture of fuel, air, and products of combustion composed of the fuel, the fraction of the air having the chemically correct mass of oxygen to completely burn the fuel, the air in excess of said chemically correct mass of air, called excess air, and the products of combustion wherein said excess air in combination with said products of combustion is called diluent, and where the diluent thermal capacitance is defined as the product of the mass average specific heat at constant pressure of the diluent times the mass of the diluent present in the combustion chamber and cylinder of the engine at the end of the intake stroke and where the chemical condition of "incipient misfire" can be defined by testing as follows: for a homogeneously mixed composition of air, fuel, and products of combustion at each pressure and temperature condition corresponding to ignition time in said cylinder for a specified fuel mass and air-fuel ratio, increase products of combustion concentration until misfire would occur in 15% of the ignition events, said method comprising the steps of: (1) Producing and delivering a dilute combustible air-fuel mixture to each cylinder whereby under steady-state operating conditions substantially identical air-fuel ratios and substantially identical air-fuel mixture mass flows are delivered to each intake port, (2) Controlling the flow of products of previous combustion so that the mass of said products of previous combustion at the end of the intake stroke under steady-state operating conditions is substantially identical in each cylinder and from cycle to cycle in each cylinder, under steady-state engine operating conditions, (3) Controlling the masses of air, fuel, and product of combustion present at the end of the intake stroke for each of said cylinders so that the mass of diluent in the cylinder is more than 80% of the diluent producing incipient misfire und engine operating loads which would produce significant NO X emissions for a conveniently operated engine, (4) For each cylinder: (a) introducing the mixture of step 3 into each combustion chamber, (b) producing a structured three-dimensional inducted flow of said mixture inside said combustion chamber during the intake stroke, and (c) variably controlling the flow kinetic energy and flow pattern of said three-dimensional inducted flow, thereby producing in each combustion chamber a high velocity gradient structured turbulent flow having sufficient coherence on large and intermediate scales to produce very tight microscale air-fuel-products of previous combustion statistics and high turbulent to laminar flame speed ratios for efficient controlled dilute combustion.