Approach for Improved Fuel Vaporization in a Directly Injected Internal Combustion Engine

In a cylinder of a directly injected internal combustion engine, a method comprising:

• operating the cylinder with negative valve overlap by closing an exhaust valve of a cylinder of the engine and opening an intake valve of the cylinder after the exhaust valve of the cylinder has closed as part of a four stroke engine;
• expanding a volume of the cylinder at least until a pressure within the cylinder is reduced to below an intake manifold pressure by moving a piston of the cylinder away from top dead center for at least a portion of between the closing of the exhaust valve and the opening of the intake valve;
• initiating an injection of a fuel blend directly into the cylinder via an in-cylinder injector after the exhaust valve has closed, the fuel blend including a mixture of gasoline and an alcohol, the alcohol including methanol;
• and
• adjusting at least an intake and/or exhaust valve timing responsive to an amount of the alcohol in the fuel blend.

In a cylinder of a directly injected internal combustion engine, a method comprising:

• during a cold engine start:
• operating the cylinder with negative valve overlap by closing an exhaust valve of a cylinder of the engine and opening an intake valve of the cylinder after the exhaust valve of the cylinder has closed as part of a four stroke engine;
• expanding a volume of the cylinder at least until a pressure within the cylinder is reduced to below an intake manifold pressure by moving a piston of the cylinder away from top dead center for at least a portion of between the closing of the exhaust valve and the opening of the intake valve;
• initiating a first injection of a fuel blend directly into the cylinder via an in-cylinder injector after the exhaust valve has closed, the fuel blend including a mixture of gasoline and alcohol;
• and
• initiating a second injection of the fuel blend directly into the cylinder via the in-cylinder injector after the exhaust valve has closed in a common engine cycle with the first injection;
• and
• adjusting at least an intake and/or exhaust valve timing responsive to an amount of the alcohol in the fuel blend.