Exhaust manifold arrangement
AssigneePerkins Engines Company Limited
InventorsAdriano Pacitti, Chris Barnes
Life of this patent
Estimating the term…
Abstract
A passageway is provided between branches of a multi-branch exhaust manifold to reduce the amount of backflow (iEGR) into the cylinders at low engine speeds. The passage is located upstream of the turbocharger and can be at the part of the manifold where the branches merge for entry into the turbo. The passageway allows exhaust pressure pulse modulation so that high iEGR levels (using iEGR through delayed exhaust valve closing for example) are avoided. The passage may be controllable to modulate the effect based on engine conditions.
Claims19
An internal combustion engine comprising;
- a plurality of cylinders, each of said cylinders having a corresponding exhaust valve, said cylinders being divided into at least a first set and a second set,
- an exhaust manifold, said exhaust manifold further having at least a first branch and a second branch, said first branch being in direct fluid communication with said cylinders in said first cylinder set and said second branch being in direct fluid communication with said cylinders in said second cylinder set when said corresponding exhaust valves are in an open position,
- an internal exhaust gas recirculation arrangement, allowing at least part of the exhaust gas to flow from said exhaust manifold into said cylinders during at least part of an intake stroke of said cylinders, and
- a passage located in or proximal to said exhaust manifold for fluidly connecting said first branch and said second branch adapted to reduce the flow of exhaust gas from said exhaust manifold into said cylinders.
A method of operating an internal combustion engine, said internal combustion engine comprising:
- a plurality of cylinders, each of said cylinders having a corresponding exhaust valve, said cylinders being divided into at least a first set and a second set,
- an exhaust manifold, said exhaust manifold further having at least a first branch and a second branch, said first branch being in direct fluid communication with said cylinders in said first cylinder set and said second branch being in direct fluid communication with said cylinders in said second cylinder set when said corresponding exhaust valves are in an open position, the method comprising the steps of:
- allowing at least part of the exhaust gas to flow from said exhaust manifold into said cylinders during at least part of an intake stroke of said cylinders, and
- reducing the flow of exhaust gas from said exhaust manifold into said cylinders by fluidly connecting said first branch and said second branch by means of a passage located in or proximal to said exhaust manifold.
A turbocharger for a multi-cylinder internal combustion engine, said internal combustion engine comprising;
- a plurality of cylinders, each of said cylinders having a corresponding exhaust valve, said cylinders being divided into sets,
- an exhaust manifold having at least two branches, each of said branches being in direct fluid connection with said cylinders in one of said cylinder sets when said corresponding exhaust valves are in an open position, and
- an internal exhaust gas recirculation arrangement, allowing at least part of the exhaust gasses to flow back from said exhaust manifold into said cylinders during an intake stroke of said cylinders,
- an exhaust gas inlet, at least part of said exhaust gas inlet being adapted to maintain the gas flow separation from said cylinder sets, and
- a passage adapted to fluidly connect at least said at least two branches to reduce the back flow of exhaust gasses from said exhaust manifold into said cylinders, said passage being located in said exhaust gas inlet of said turbo charger.
Dependencies are inferred from the claim text.