Systems and methods for coordinating an air blend valve with an intake air heater

A compression ignition engine comprising:

• an air intake port;
• an intake air heater disposed upstream of the air intake port;
• an air blend valve in communication with the intake air heater and the air intake port;
• and a control unit configured to:
• determine a target temperature for intake air at the air intake port;
• determine a maximum port temperature for the air blend valve;
• designating the intake air heater or the air blend valve as a primary actuator for controlling temperature of the intake air, based on the maximum port temperature of the air blend valve;
• control the temperature of the intake air based on the designated primary actuator, wherein determining the maximum port temperature for the air blend valve comprises inputting one or more temperature measurements from a charge air cooler, wherein:
• the charge air cooler includes a high-temperature portion and a low-temperature portion;
• and inputting one or more temperature measurements from the charge air cooler comprises measuring temperatures at an outlet of the high-temperature portion and at an outlet of the low-temperature portion, wherein designating the primary actuator comprises designating the air blend valve as the primary actuator if the target temperature is less than the maximum port temperature for the air blend valve, and wherein designating the primary actuator comprises designating the intake air heater as the primary actuator if the target temperature is greater than or equal to the maximum port temperature for the air blend valve.

A non-transitory computer-readable storage medium having computer-readable instructions stored thereon, which when executed by a computer cause the computer to perform a method comprising:

• determining a target temperature for intake air at an air intake port of a compression ignition engine;
• determining a maximum port temperature for an air blend valve of the compression ignition engine;
• designating an intake air heater or the air blend valve as a primary actuator for controlling temperature of the intake air, based on the maximum port temperature of the air blend valve;
• controlling the temperature of the intake air based on the designated primary actuator, wherein determining the maximum port temperature for the air blend valve comprises inputting one or more temperature measurements from a charge air cooler, wherein:
• the charge air cooler includes a high-temperature portion and a low-temperature portion;
• and inputting one or more temperature measurements from the charge air cooler comprises measuring temperatures at an outlet of the high-temperature portion and at an outlet of the low-temperature portion, wherein designating the primary actuator comprises designating the air blend valve as the primary actuator if the target temperature is less than the maximum port temperature for the air blend valve, and wherein designating the primary actuator comprises designating the intake air heater as the primary actuator if the target temperature is greater than or equal to the maximum port temperature for the air blend valve.