TEMPERATURE CONTROL FOR TURBOCHARGED ENGINE

摘要

A cooling apparatus (10) and method for a turbocharged internal combustion engine (12). The combustion air (16) exiting a turbocharger (18) is passed over an air-to-water intercooler (40) then over an air-to-air intercooler (4 2) for heat exchange with liquid coolant and with ambient air (32) respectively . During periods of low ambient air temperature, the combustion air may be directed through a bypass duct (80) around the air-to-air intercooler, and further, may be heated by the coolant in the air-to-water intercooler. A mul ti- speed fan (44) and/or shutters (48) may be used to control the flow of ambie nt air across the air-to-air intercooler. A cooling duct (68) provides a flow o f ambient air to the fan motor (46) during periods of operation when the flow of ambient air over the air-to-air heat exchanger is restricted by the shutters . Coolant exiting a subcooler (28) has the lowest temperature in the system an d is directed to a lube oil cooler (34) for engine lubricant cooling.