Abstract:
A variable intake air device forms a long port and a short port in each of branches of an intake air manifold. The variable intake air device switches between the long port and the short port. A gas introduction device draws gas into each of the branches. When the engine is in a high load region, the variable intake air device uses the long port, when an engine rotation speed is less than a predetermined rotation speed, and uses the short port, when the engine rotation speed is greater than or equal to the predetermined rotation speed. When the engine is in a low load region, the variable intake air device switches between the long port and the short port according to the engine rotation speed.
Abstract:
An exhaust manifold to be connected to an internal combustion engine with a plurality of exhaust ports in the present invention includes a first upper shell member, a second upper shell member, and a lower shell member. The first upper shell member and the lower shell member are superposed on each other to thereby form a first flow passage to be connected to at least one exhaust port out of the plurality of exhaust ports. The second upper shell member is superposed on the lower shell member with the first upper shell member sandwiched therebetween such that at least a part of the first upper shell member is exposed, to thereby form a second flow passage to be connected to another at least one exhaust port out of the plurality of exhaust ports.
Abstract:
A low emissions 2-stroke natural gas fueled engine includes at least one cylinder with an exhaust port in communication with a silencer/catalytic converter unit. The unit has first and second volumes in communication with each other. The first volume dampens spurious exhaust pressure excursions and removes particulates in the exhaust. The second volume houses an oxidation catalyst for treating exhaust to reduce exhaust emissions. The engine oil has at most 10 ppm zinc content to reduce metal poisons contained in the exhaust prior to contact with the oxidation catalyst. The engine oil preferably has a very low ash content to minimize sulfur combustion components in the exhaust to reduce masking of the oxidation catalyst. The first volume preferably has a pressure relief valve set to relieve at a pressure greater than the maximum normal operating pressure of the engine to avoid excessive pressure excursions of the engine exhaust from damaging the oxidation catalyst.
Abstract:
The invention comprises a cylinder block wherein vertical reciprocation of a piston is transmitted to a connecting rod that rotates a crank shaft to generate torque. A cylinder head is joined to the top of the cylinder block, whereof one side is connected to a primary intake and exhaust manifold which is opened and shut by a primary intake and exhaust valve and the other side is connected to a secondary intake and exhaust manifold which is opened and shut by a secondary intake and exhaust valve. A primary cam shaft drives the primary intake and exhaust valve. A secondary cam shaft drives the secondary intake and exhaust valve. A tertiary cam shaft is placed on the upper side of the cylinder head and rotates to interlock with the rotation of the secondary cam shaft. Therefore, intake and exhaust performance of a four-stroke internal combustion engine is improved.
Abstract:
An exhaust system has first and second exhaust gas turbochargers for a V-8 internal combustion engine having an ignition sequence of a 90° crank angle from one cylinder to the next in each of two cylinder banks. The exhaust system includes a first-through-fourth exhaust lines from the cylinders to the two exhaust gas turbochargers, with two cylinders respectively being assigned to an exhaust line. One exhaust turbocharger is respectively assigned to two exhaust lines. The two cylinders assigned to an exhaust line having an ignition interval of a 360° crank angle. The first and the second exhaust lines assigned to an exhaust gas turbocharger having an ignition sequence displaced with respect to one another by a 180° crank angle. As a result, the opening phase of the charge cycle intake valves can be prolonged, which leads to a significantly higher power of the internal combustion engine.
Abstract:
A method of improving scavenging operation of a two-stroke internal combustion engine. The exhaust pressure of the engine is analyzed to determine if there is a pulsation frequency. Acoustic modeling is used to design an absorber. An appropriately designed side branch absorber may be attached to the exhaust manifold.
Abstract:
The proposed device for controlling vortex structures (5) in a turbulent air jet (3) flowing out of the air exhaust channel, which is constituted by at least one pair of needles (1) connected to an AC voltage source to create a pulsating corona discharge between the needles. One needle is located along and the other across the flow to produce a resonant effect of the pullsating corona discharge on the vortex structures. hi the proposed method for controlling vortex structures in a turbulent air jet, at least one pair of needles connected to an AC voltage source to create a pulsating corona discharge between the needles. One needle is located along and the other across the flow to produce a resonant effect of the pulsating corona discharge on the vortex structures.
Abstract:
An internal combustion engine includes a structure that increases the velocity of exhaust gas. The internal combustion engine includes a branch section arranged to branch a shock wave propagating at a higher velocity than exhaust gas and to guide the branched shock wave, and a reflecting section provided in the branch section. The reflecting section is arranged to reflect and return the shock wave back to an exhaust path and cause the shock wave to collide against the exhaust gas, thereby increasing the pressure of the exhaust gas. In accompaniment with the exhaust gas passing a divergent section of a convergent-divergent nozzle, a new shock wave propagating in a downstream direction in the exhaust path is generated, and the temperature and pressure of the exhaust gas are decreased.
Abstract:
A muffler includes a case divided into three chambers by two baffles. The first chamber is closest to, and the third chamber is farthest from, the exhaust pipe. An inlet pipe has a first end connected to the exhaust pipe, and a second end in fluid communication with the third chamber. An outlet pipe expels exhaust and water from the first chamber to the exterior. A connecting pipe provides fluid communication between the first and third chambers. The second end of the inlet pipe is above the bottom interior surface of the outlet pipe. The inlet pipe may have holes in the second chamber, above the bottom interior surface of the outlet pipe. The connecting pipe may have holes in the second chamber. The baffles may have holes for the water to flow from the second and third chambers to the first chamber. Also, an exhaust apparatus utilizing the muffler.
Abstract:
A rotatable sound attenuation device is provided comprising a central portion rotatable about a first axis, a radial portion extending outwardly from the central portion and a chamber having a closed first end and a second end opening radially outwardly of the radial portion and defining a second axis therein having a radial component thereto. A piston is disposed within the chamber and is moveable to a location along the second axis in response to a centrifugal force imparted on the piston by rotation of the central portion and the radial portion about the first axis. A biasing member operates to limit movement of the piston along the second axis. A quarter wave chamber is defined by the second, open end of the chamber and the piston and has a sound attenuating length defined by the location of the piston along the second axis of the chamber.