A wall temperature acquisition unit acquires a wall temperature of an internal combustion engine. A wall temperature adjustment unit adjusts the wall temperature. A ratio adjustment unit adjusts a gas ratio that is acquired by dividing a mass flow amount of gas supplied to the internal combustion engine by a mass flow amount of fuel supplied to the internal combustion engine. The wall temperature adjustment unit performs a low wall temperature control to maintain the wall temperature at a low temperature when the internal combustion engine is at a high load and a high wall temperature control to maintain the wall temperature at a high temperature when the internal combustion engine is at a low load. The ratio adjustment unit adjusts the gas ratio based on the wall temperature, when switching between the low wall temperature control and the high wall temperature control is performed.

An internal combustion system capable of exactly determining timing of exchanging a coolant of an engine. The internal combustion system includes an engine, cooling circulation mechanism circulating the coolant containing ethylene glycol to the engine while cooling it, temperature sensor measuring the temperature of the coolant having passed through the engine, and control device. The control device includes a number of cold starts counting unit determining engine cold start and counting the number of cold starts before coolant exchange, an accumulated amount of time measuring unit measuring an accumulated amount of time when the coolant temperature measured by the temperature sensor is a defined temperature or higher before the coolant exchange, and an exchange determination unit determining the need for coolant exchange, when the accumulated amount of time is a defined amount of time or greater and the number of cold starts is a defined number of times or greater.

An internal combustion system includes a control device having an accumulated amount of time measuring unit that measures an accumulated amount of time by measuring an amount of time when the temperature of the coolant measured by a temperature sensor is equal to or higher than a defined temperature and accumulating the amount of time measured, an exchange determination unit that determines that the coolant needs to be exchanged when the measured accumulated amount of time reaches or exceeds an upper-limit accumulated amount of time, and an upper-limit amount of time setting unit that sets the upper-limit accumulated amount of time for determination by the determination unit in accordance with the type of metal forming the flow channel where the coolant flows.

An internal combustion engine includes an engine block, a combustion cylinder including a cylinder wall, engine oil and engine coolant. Control of the internal combustion engine includes estimating the cylinder wall temperature in a temperature state estimator, comparing the estimated cylinder wall temperature to a predetermined temperature threshold, and circulating the engine coolant in the engine when the estimated cylinder wall temperature exceeds the predetermined temperature threshold.

A method of controlling a fluid heater control system for a locomotive, the fluid heater control system including a heater assembly including a water pump and a heating element, the method including determining if a fuel pump of the locomotive is on, if the fuel pump is off, activating the heater assembly, running the water pump for a first predetermined period of time, determining if a temperature of the fluid is greater than a first predetermined threshold, and if the temperature of the fluid is greater than the first predetermined threshold, deactivating the water pump for a second predetermined time period.

A cooling system is provided to cool an engine of a vehicle, which includes a cooling water passage through which cooling water is supplied to a water jacket formed in the engine, and having an undercover cooling water passage provided in an undercover, a radiator provided in the cooling water passage and configured to cool the cooling water by exchanging heat with air flowing into an engine bay from a grille, a flow rate adjuster configured to adjust a cooling water flow rate supplied to the undercover cooling water passage, and a controller configured to acquire a temperature of the cooling water of the water jacket in the engine and, when the temperature is above a temperature threshold, control the flow rate adjuster to increase the flow rate of the cooling water supplied to the undercover cooling water passage compared to when the acquired temperature is below the temperature threshold.

The present invention provides a battery temperature control system having a simple configuration and capable of immediately raising a battery temperature by actively using heat generated by an internal combustion engine. The battery temperature control system includes: an engine cooling circuit in which a coolant in an internal combustion engine is circulated between a coolant jacket and a radiator by a coolant pump; an exhaust heat recovery circuit in which a coolant in an EGR cooler that recovers exhaust heat of the internal combustion engine flows; a battery cooler-destined branch circuit that is branched from the engine cooling circuit and goes toward an upstream side of the battery cooler in the battery cooling circuit 11; and a channel switching mechanism that selectively connects a downstream side of at least one of the exhaust heat recovery circuit or the battery cooler-destined branch circuit to the upstream side of the battery cooler in the battery cooling circuit.

A control valve according to the present invention is configured such that when a third opening part, which is an auxiliary opening part, and a third discharge opening, which is an auxiliary connection opening, do not overlap, the third opening part and a continuous discharge opening overlap. Thus, for example, when a flow rate of cooling water for continuous circulation is required, such as during a cold start, cooling water guided through an internal passage is discharged via the continuous discharge opening in addition to cooling water guided from a bypass passage, thereby ensuring a sufficient flow rate of cooling water for continuous circulation.

A cooling system is mounted on an internal combustion engine equipped with an EGR device including an EGR passage. The cooling system includes: an intercooler disposed in the intake passage; an EGR cooler disposed in the EGR passage; a condensed water discharger configured to discharge condensed water generated in the EGR cooler from the EGR passage; a radiator configured to cool a first coolant to or below a dew point of the EGR gas flowing into the EGR cooler; a first circulation flow path configured to circulate the first coolant in the order of the radiator, the EGR cooler, and the intercooler; and a pump disposed in the first circulation flow path and configured to circulate the first coolant such that an outlet gas temperature of the EGR cooler is equal to or lower than the dew point of the EGR gas flowing into the EGR cooler.

A coolant circuit in a vehicle includes a first flow control unit disposed in a main duct between an engine and a radiator. The first flow control unit, as a function of a temperature of a coolant, thermostatically controls a flow of the coolant. A bypass duct is fluidically disposed parallel to the radiator where the bypass duct opens into the main duct after the radiator and branches off the main duct between the engine and the first flow control unit. A second flow control unit is disposed in the bypass duct where the second flow control unit is configured such that the second flow control unit opens or closes the bypass duct as a function of the temperature of the coolant.