A fluid circuit for a trucking vehicle having a transport refrigeration unit is provided. The fluid circuit includes a first regulator assembly defining a first fuel inlet that is arranged to receive fuel from a first fuel tank and a first fuel outlet that is arranged to provide fuel to a first engine. The first regulator assembly having a first heat exchanger assembly defining a first coolant inlet that is arranged to receive coolant from a cooling system associated with the first engine and a first coolant outlet that is arranged to provide coolant to the cooling system.

Methods and systems are provided for controlling coolant flow through parallel branches of a coolant circuit including an AC condenser and a charge air cooler. Flow is apportioned responsive to an AC head pressure and a CAC temperature to reduce parasitic losses and improve fuel economy. The flow is apportioned via adjustments to a coolant pump output and a proportioning valve.

Methods and systems are provided for controlling coolant flow through parallel branches of a coolant circuit including an AC condenser and a charge air cooler. Flow is apportioned responsive to an AC head pressure and a CAC temperature to reduce parasitic losses and improve fuel economy. The flow is apportioned via adjustments to a coolant pump output and a proportioning valve.

A chiller system includes an intercooler configured to cool compressed charge air received from a charger, a low temperature cooling circuit fluidly coupled to the intercooler, and an air conditioner circuit circulating a refrigerant and having a primary circuit and a bypass circuit. The primary circuit includes a compressor, a condenser, and an evaporator. The bypass circuit includes a conduit that bypasses the evaporator, and a chiller shut off valve is configured to selectively prevent refrigerant from flowing through the bypass circuit. A chiller is thermally coupled to the low temperature cooling circuit and the bypass circuit. A controller is in signal communication with the chiller shut off valve. The controller is programmed to, upon receiving a signal indicating a driver has manually selected the vehicle to operate in a racing mode, open the chiller shut off valve to provide increased cooling to the intercooler and the compressed charge air.

A chiller system includes an intercooler configured to cool compressed charge air received from a charger, a low temperature cooling circuit fluidly coupled to the intercooler, and an air conditioner circuit circulating a refrigerant and having a primary circuit and a bypass circuit. The primary circuit includes a compressor, a condenser, and an evaporator. The bypass circuit includes a conduit that bypasses the evaporator, and a chiller shut off valve is configured to selectively prevent refrigerant from flowing through the bypass circuit. A chiller is thermally coupled to the low temperature cooling circuit and the bypass circuit. A controller is in signal communication with the chiller shut off valve. The controller is programmed to, upon receiving a signal indicating a driver has manually selected the vehicle to operate in a racing mode, open the chiller shut off valve to provide increased cooling to the intercooler and the compressed charge air.

An air cooling system for a vehicle engine includes an air intake configured to receive intake air for delivery to the engine, a first coolant loop thermally coupled to the air intake to provide cooling to the intake air, and a second coolant loop thermally coupled to the air intake to provide further cooling to the intake air. The first and second coolant loops are separate loops using a common condenser

An air cooling system for a vehicle engine includes an air intake configured to receive intake air for delivery to the engine, a first coolant loop thermally coupled to the air intake to provide cooling to the intake air, and a second coolant loop thermally coupled to the air intake to provide further cooling to the intake air. The first and second coolant loops are separate loops using a common condenser

Methods and systems are provided for selectively re-cooling intake air downstream of a charge air cooler. In one example, a system may include a cylinder head defining a plurality of cylinders, the cylinder head including a plurality of inlet ports each fluidically coupled to a respective cylinder, a refrigerant supply, and a refrigerant passage surrounding each inlet port and fluidically coupled to the refrigerant supply, the refrigerant passage shaped to correspond to an outer profile of each inlet port.

Methods and systems are provided for selectively re-cooling intake air downstream of a charge air cooler. In one example, a system may include a cylinder head defining a plurality of cylinders, the cylinder head including a plurality of inlet ports each fluidically coupled to a respective cylinder, a refrigerant supply, and a refrigerant passage surrounding each inlet port and fluidically coupled to the refrigerant supply, the refrigerant passage shaped to correspond to an outer profile of each inlet port.

Methods and systems are provided for cooling charge air in a hybrid engine. In one example, a method may include cooling charge air by a combination of air-to-air and air-to-coolant heat transfer with assistance from a chiller arranged in the coolant circuit. The coolant circuit includes an insert coupled to a charge air cooler allowing heat exchange via conduction and convection.