Cross-Port Air Flow To Reduce Pumping Losses

A method of reducing pumping losses using cross-port air flow in an internal combustion engine system, wherein the internal combustion engine system comprises:

• a plurality of cylinder assemblies comprising a first cylinder assembly and a second cylinder assembly;
• the first cylinder assembly comprising a first throttle operationally affixed to control combustion air flow into a first cylinder through a first intake port;
• the second cylinder assembly comprising a second throttle operationally affixed to control combustion air flow into a second cylinder through a second intake port;
• an intake-interconnecting port system comprising:
• a first interconnecting port connecting the first intake port downstream of the first throttle to the second intake port downstream of the second throttle;
• and
• a first valve within the first interconnecting port;
• the method comprising:
• opening one or more interconnecting ports during part-throttle mode operation;
• opening the first throttle to compensate for reduced engine output caused by lower charge density in the first cylinder due to reduced filling inertia of the primary combustion air flow through the first intake port;
• wherein the reduced filling inertia is caused by the cross-port air flow;
• and
• further wherein opening the first throttle reduces cylinder vacuum in the first cylinder and thus reduces induction system pumping work and improves fuel economy.

A method of reducing pumping losses using cross-port air flow in an internal combustion engine system, wherein the internal combustion engine system comprises:

• a plurality of cylinder assemblies comprising a first cylinder assembly and a second cylinder assembly;
• the first cylinder assembly comprising a first throttle operationally affixed to control primary combustion air flow into a first cylinder through a first intake port;
• the second cylinder assembly comprising a second throttle operationally affixed to control primary combustion air flow into a second cylinder through a second intake port;
• a first port connecting the first intake port downstream of the first throttle to the second intake port downstream of the second throttle;
• and
• a first valve within the first connecting port;
• the method comprising:
• operating the internal combustion engine system in part-throttle mode;
• opening the first valve during part-throttle mode operation to permit cross-port air flow from the second intake port to the first intake port through the first connecting port;
• opening the first throttle to compensate for reduced engine output caused by lower charge density in the first cylinder due to reduced filling inertia of the primary combustion air flow through the first intake port;
• wherein the reduced filling inertia is caused by the cross-port air flow;
• and
• further wherein opening the first throttle reduces cylinder vacuum in the first cylinder and thus reduces induction system pumping work and improves fuel economy.