Method and device for operating an internal combustion engine

A method for operating an internal combustion engine having a cylinder and an intake duct with a main path that opens into an inlet of the cylinder, comprising:

• configuring a tank purging valve to control initiation of a tank purging flow into the intake duct at an inlet point upstream of the respective inlet of the cylinder;
• configuring a recirculation path in parallel with the main path where the recirculation path has:
• a recirculation inlet arranged in the main path,
• a recirculation control element arranged in the recirculation path that controls the opening of the recirculation path, and
• a recirculation outlet arranged into the main path upstream of the recirculation inlet;
• and
• determining a cylinder tank purging fuel mass that flows into a cylinder during the working cycle of the cylinder to a previous measuring in of fuel, where the cylinder tank purging fuel mass is determined as a function of an opening angle of the tank purging valve and an opening angle of the recirculation control element.

An internal combustion engine system, comprising:

• a block having a cylinder;
• a crank shaft rotably mounted in the block;
• a piston arranged in the cylinder of the block;
• a cylinder head arranged on the block;
• a cylinder inlet arranged in the cylinder head;
• an intake duct connected to the cylinder inlet having a main path that inlets an inlet flow into the cylinder;
• a tank purging valve arranged at an inlet point upstream of the cylinder inlet the tank purging valve configured to control an initiation of a tank purging flow into the intake duct;
• a recirculation path arranged parallel to the main path and configured with:
• a recirculation inlet arranged at a union of the recirculation path and the main path,
• a recirculation control element arranged in the recirculation path that controls the opening of the recirculation path, and
• a recirculation outlet arranged at a union of the recirculation path and the main path upstream relative to the recirculation inlet;
• a first cylinder tank purging fuel mass determining device that determines a cylinder tank purging fuel mass that flows into the cylinder during the working cycle of the cylinder to a previous measuring in of fuel;
• and
• a second cylinder tank purging fuel mass determining device that determines a cylinder tank purging fuel mass as a function of an opening angle of the tank purging valve and an opening angle of the recirculation control element.