Internal combustion engines

A piston ported two-stroke compression ignition internal combustion engine comprising:

• a cylinder, a cylinder head defining a fixed closed end of the cylinder, and a piston for reciprocation within the cylinder, wherein the closed end of the cylinder and the piston together define a combustion chamber therebetween;
• at least one heater mount for holding a heater to heat the combustion chamber;
• a sensor mount in the cylinder head for mounting a sensor to detect a characteristic indicative of a temperature of the combustion chamber during reciprocation of the piston within the cylinder, and to output a signal in dependence on the characteristic detected;
• and
• a controller to:
• determine whether the temperature of the combustion chamber has fallen below, or is at or above, a threshold temperature during reciprocation of the piston within the cylinder, on the basis of the signal outputted by the sensor;
• increase a temperature of the heater, when the heater is held by the heater mount, to heat the combustion chamber when the controller determines that the temperature of the combustion chamber has fallen below the threshold temperature during reciprocation of the piston within the cylinder;
• and
• reduce the temperature of the heater, when the heater is held by the heater mount and when the controller determines that the temperature of the combustion chamber is at or above the threshold temperature during reciprocation of the piston within the cylinder.

A non-transitory machine-readable storage medium storing instructions that, when executed by a controller of a piston ported two-stroke compression ignition internal combustion engine, the engine comprising a cylinder, a cylinder head defining a fixed closed end of the cylinder, and a piston for reciprocation within the cylinder, wherein the closed end of the cylinder and the piston together define a combustion chamber therebetween, and at least one heater to heat the combustion chamber, and a sensor mounted in the cylinder head to detect a characteristic indicative of a temperature of the combustion chamber during reciprocation of the piston within the cylinder, and to output a signal in dependence on the characteristic detected;

• and the controller to control the heater to heat the combustion chamber, cause the controller to:
• determine whether a temperature of the combustion chamber has fallen below or is at or above, a threshold temperature during reciprocation of the piston within the cylinder, on the basis of the signal outputted by the sensor;
• increase a temperature of the heater to heat the combustion chamber, when the controller determines that the temperature of the combustion chamber has fallen below the threshold temperature during reciprocation of the piston within the cylinder;
• and
• reduce the temperature of the heater when the controller determines that the temperature of the combustion chamber is at or above the threshold temperature during reciprocation of the piston within the cylinder.

An engine control unit comprising a non-transitory machine-readable storage medium, the non-transitory machine-readable storage medium storing instructions that, when executed by a controller of a piston ported two-stroke compression ignition internal combustion engine, the engine comprising a cylinder, a cylinder head defining a fixed closed end of the cylinder, and a piston for reciprocation within the cylinder, wherein the closed end of the cylinder and the piston together define a combustion chamber therebetween, and at least one heater to heat the combustion chamber, and a sensor mounted in the cylinder head to detect a characteristic indicative of a temperature of the combustion chamber during reciprocation of the piston within the cylinder, and to output a signal in dependence on the characteristic detected;

• and the controller to control the heater to heat the combustion chamber, cause the controller to:
• determine whether a temperature of the combustion chamber has fallen below or is at or above, a threshold temperature during reciprocation of the piston within the cylinder, on the basis of the signal outputted by the sensor;
• increase a temperature of the heater to heat the combustion chamber, when the controller determines that the temperature of the combustion chamber has fallen below the threshold temperature during reciprocation of the piston within the cylinder;
• and
• reduce the temperature of the heater when the controller determines that the temperature of the combustion chamber is at or above the threshold temperature during reciprocation of the piston within the cylinder.