Method and apparatus for intercooling the charge air of a pressure-charged internal combustion engine

Claim 2

In a method for intercooling the charge air of a pressure-charged internal combustion engine by way of an air-cooled heat exchanger, wherein the internal combustion engine is pressure-charged with a gas-dynamic pressure-wave machine, the improvement which comprises the steps of: dividing the entire quantity of outside air drawn-in by the pressure-wave machine into a partial stream of scavenging air and a partial stream of charge air; directing the scavenging air to flow as a coolant through the heat exchanger and upon leaving the latter directing said scavenging air through said pressure wave machine so as to perform its intended scavenging function in the pressure-wave process; and compressing the charge air in the pressure-wave machine and intercooling the compressed charge air upon bearing the pressure-wave machine by passing such compressed charge air in the heat exchanger cooled by the scavenging air.

Claim 3

The method as defined in claim 1, including the step of: selecting the partial stream of scavenging air to be equal to at least 40% of the charge-air flow rate over the utilized full-load speed range of the internal combustion engine.

Claim 4

The method as defined in claim 1, further including the steps of: admitting the scavenging air and charge air spatially separated from one another to the pressure-wave process performed by the pressure-wave machine.

Claim 5

The method as defined in claim 3, wherein: when considered in the sequence of events of the pressure-wave process, introducing the scavenging air into the process before the charge air.

Claim 6

The method as defined in claim 1, used in conjuction with an internal combustion engine having an air-side pressure greater than 1.5.

Claim 7

In an apparatus for intercooling the charge air of a pressure-charged internal combustion engine by way of an air-cooled heat exchanger, wherein the internal combustion engine is pressure-charged with a gas-dynamic pressure-wave machine performing a pressure-wave process, the improvement which comprises: said pressure-wave machine having a low-pressure air inlet port; an air casing provided for the pressure-wave machine; an air intake stub provided for said air casing; partition means for dividing the air casing of the pressure-wave machine from the air intake stub to the low-pressure air inlet port into two ducts, wherein one of said ducts has scavenging air flowing therethrough and the other of said ducts has charge air flowing therethrough; a heat exchanger cooperating with said pressure-wave machine; said heat exchanger being located in said one of said two ducts provided for the scavenging and compressed charge air.

Claim 8

In an apparatus for intercooling the charge air of a pressure-charged internal combustion engine by way of an air-cooled heat exchanger, wherein the internal combustion engine is pressure-charged with a gas-dynamic pressure-wave machine performing a pressure-wave process, the improvement which comprises: said pressure-wave machine having a low-pressure air inlet port; an air casing provided for the pressure-wave machine; an air intake stub provided for said air casing; partition means for dividing the air casing of the pressure-wave machine from the air intake stub to the low-pressure air inlet port into two ducts, wherein one of said ducts has scavenging air flowing therethrough and the other of said ducts has charge air flowing therethrough; a heat exchanger cooperating with said pressure-wave machine; said heat exchanger being located in said one of said two ducts provided for the scavenging and compressed charge air.

Claim 9

The apparatus as defined in claim 6, wherein: said air casing is provided with a high-pressure air duct; said heat exchanger being connected with the high-pressure air duct of the air casing.

Claim 10

The apparatus as defined in claim 5, wherein: said heat exchanger comprises a recuperative cooler wherein the coolant flows transversely to the charge air.