초록 ▼

Various systems and method for heating an engine in a vehicle are described. In one example, intake air flowing in a first direction may be heated via a gas-to-gas heat exchange with exhaust gases. The heated intake air may then be used in a subsequent gas-to-liquid heat exchange to heat a fluid cir

Various systems and method for heating an engine in a vehicle are described. In one example, intake air flowing in a first direction may be heated via a gas-to-gas heat exchange with exhaust gases. The heated intake air may then be used in a subsequent gas-to-liquid heat exchange to heat a fluid circulating through the engine. In another example, intake air flowing in a second direction may be heated via a heat exchange with exhaust gases in order to cool an exhaust catalyst.

대표청구항 ▼

1. A vehicle engine heating method, comprising: heating intake air with exhaust gas via a gas-to-gas heat exchanger being in an engine exhaust passage positioned upstream of an exhaust catalyst and downstream of a turbocharger turbine while heating a fluid flowing through the engine with the heated

1. A vehicle engine heating method, comprising: heating intake air with exhaust gas via a gas-to-gas heat exchanger being in an engine exhaust passage positioned upstream of an exhaust catalyst and downstream of a turbocharger turbine while heating a fluid flowing through the engine with the heated intake air via a gas-to-liquid heat exchanger; andcooling the exhaust catalyst with intake air via the gas-to-gas heat exchanger during turbocharger boosting of intake air above atmospheric pressure. 2. The method of claim 1 wherein intake airflow direction is opposite during catalyst cooling as compared to intake air heating. 3. The method of claim 2 wherein airflow direction is reversed via increased boost, the reversed intake airflow further cooling the fluid. 4. The method of claim 1 wherein during intake air heating via the gas-to-gas heat exchanger and cooling via the gas-to-liquid heat exchanger, the intake air is maintained warmer than ambient air after cooling via the gas-to-liquid heat exchanger. 5. The method of claim 1, wherein the fluid is at least one of engine oil, engine coolant, or transmission oil. 6. The method of claim 1, wherein an amount of heated intake air is adjusted via an air bypass valve. 7. The method of claim 1, further comprising heating the intake air and the fluid during a cold engine start. 8. A method for a turbocharged engine in a vehicle, the engine having an exhaust catalyst, comprising: heating uncompressed intake air via a gas-to-gas heat exchanger, the gas-to-gas heat exchanger in communication with exhaust gases and positioned upstream of an exhaust catalyst;passing the heated uncompressed intake air through a gas-to-liquid heat exchanger to heat a fluid that flows through the engine and to reduce a temperature of the heated intake air;delivering the uncompressed heated intake air to a cylinder of the engine via an air bypass valve; andcooling the exhaust catalyst or engine oil when a turbocharger is in operation and boost is greater than ambient pressure;and cooling compressed intake air during turbocharger operation with a charge air cooler. 9. The method of claim 8, wherein the fluid is at least one of engine oil, engine coolant, or transmission oil. 10. The method of claim 8, wherein the method is carried out under cold start conditions when the turbocharger is not in operation. 11. The method of claim 8, wherein an amount of uncompressed heated intake air delivered to the engine is adjusted via the air bypass valve. 12. A heating system for an engine, comprising: a throttle in an intake passage of the engine;an air bypass valve;a turbocharger;a charge air cooler positioned downstream of the turbocharger in the intake passage of the enginean exhaust catalyst;a gas-to-gas heat exchanger in communication with exhaust gases and intake air;a gas-to-liquid heat exchanger in communication with intake air and a fluid circulating through the engine; anda control system comprising a computer readable storage medium, the medium comprising instructions for: during a first operating condition, adjusting openings of the throttle and air bypass valve such that intake air flows in a first direction through the gas-to-gas heat exchanger and then the gas-to-liquid heat exchanger and heated air enters a cylinder of the engine;during a second operating condition, adjusting the openings of the throttle and air bypass valve such that intake air flows in a second direction through the air bypass valve, the second direction being the reverse of that during the first operating condition, and the exhaust catalyst is cooled; andduring a third operating condition, closing the air bypass valve. 13. The heating system of claim 12, wherein the first operating condition includes cold engine start while the turbocharger is not in operation. 14. The heating system of claim 12, wherein the exhaust catalyst is positioned upstream of the gas-to-gas heat exchanger, and the second operating condition includes boost greater than a threshold value when the turbocharger is in operation. 15. The heating system of claim 12, wherein the third operating condition includes fluid temperature greater than a threshold temperature. 16. The heating system of claim 12, wherein the third operating condition includes fluid temperature less than a threshold temperature when the engine is boosted. 17. The heating system of claim 12, wherein the third operating condition includes time since start. 18. The heating system of claim 12, further comprising instructions for adjusting air-fuel control based on an operating condition of the engine.