A control system for a dual fuel engine having a liquid fuel supply and a gaseous fuel supply is disclosed. The control system may include at least one sensor operably coupled to a cylinder of the dual fuel engine and configured to monitor cylinder condition and transmit a cylinder condition signal. Additionally, a controller may be communicably coupled with the at least one sensor and the controller may be configured to receive the cylinder condition signal and determine whether the cylinder is operating in an abnormal operating condition. Whereas the controller determines the cylinder is operating in the abnormal operating condition, the controller sends a control signal for the liquid fuel supply to provide an amount of liquid fuel which is greater than an amount of liquid fuel supplied to the cylinder during a normal operating condition.

Both an improvement in detection accuracy of a valve opening position of a blocking valve and a reduction in time required for learning of the valve opening position are achieved. An evaporated fuel processing apparatus is provided with a learning device configured to learn the valve opening position of the blocking valve. The learning device learns the valve opening position (i) by stepwisely increasing a stroke amount by rotating a stepping motor by two steps at each time in a valve opening direction and (ii) by determining whether a difference between the stroke amount at present and the stroke amount corresponding to the valve opening position is one step of rotation of the stepping motor, or two steps, on the basis of pressure fluctuation on the canister side of the blocking valve associated with the rotation of the stepping motor when the blocking valve is opened, when learning the valve opening position.

A method for controlling a dual fuel engine system includes determining a friction power loss amount of an internal combustion engine of the dual fuel engine system, where the friction power loss amount is based on an engine speed of the internal combustion engine and a friction torque estimate. The method also includes determining an accessory power loss amount of a power of the internal combustion engine, where the accessory power loss amount is based on the engine speed and an accessory torque estimate. The method further includes estimating a net engine power amount based on the accessory power loss amount and a brake power amount of the internal combustion engine, estimating an indicated diesel power, and estimating, based on the estimated net engine power, a first indicated engine power and a first gas power.

Technologies for combusting hazardous compounds such as chemical warfare agents and related compounds are disclosed. In embodiments, the technologies include systems and methods for combusting such compounds in an internal combustion engine, such as a spark ignition internal combustion engine, a diesel engine, or the like. The technologies described herein further include components for treating an exhaust gas stream produced by combustion of hazardous compounds. In embodiments such components include a scrubber that utilizes a scrubbing media such as soil to removing acid gases from the exhaust stream.

A method of reducing carbonaceous deposits on a fuel injector is provided in which a first fuel composition is supplied to the fuel injector in a dual fuel engine, the first fuel composition comprising natural gas fuel and a first percentage of diesel fuel; and a second fuel composition is supplied to the fuel injector in a dual fuel engine, the second fuel composition comprising a second percentage of diesel fuel that is greater than the first percentage of diesel fuel to cause cavitation to occur within the fuel injector, thereby reducing carbonaceous deposits.

Premixed engines including dual fuel engines can experience abnormal combustion characteristics including misfire, pre-ignition and knock. A method for detecting and mitigating abnormal combustion in an engine comprises sensing frequency components of an acoustic signal associated with a combustion chamber during a combustion cycle, the frequency components representative of at least one of a normal and an abnormal combustion characteristic; determining an in-cylinder pressure signal as a function of the acoustic signal; calculating as functions of the in-cylinder pressure signal at least one of a knock index, a gross indicated mean effective pressure and a start of combustion timing; detecting the abnormal combustion characteristic is at least one of (a) a misfire event when the gross indicated mean effective pressure is less than a predetermined mean effective pressure value; (b) a pre-ignition event when the start of combustion timing is advanced of a start of ignition timing; and (c) an engine knock event when the knock index is greater than a predetermined knock value; and performing a mitigation strategy for the detected abnormal combustion characteristic.

An internal combustion engine in which an output from a fuel reformation cylinder (2) is obtained based on a cylinder internal pressure and a rotational speed of the fuel reformation cylinder, and an output adjusting operation for adjusting an output from an output cylinder (3) is executed so that a sum of the output from the fuel reformation cylinder and the output from the output cylinder matches with a required engine power. In this output adjusting operation, during a transient operation in which the required engine power is increased, the output from the output cylinder is increased by increasing the fuel supply amount to a combustion chamber (33). Then, the fuel supply amount to a fuel reformation chamber (23) is gradually increased while the fuel supply amount to the combustion chamber is gradually reduced, so that a heat source is shifted from the fuel to the reformed fuel.

An engine device including: an intake manifold configured to supply air into a cylinder; an exhaust manifold configured to output exhaust gas from the cylinder; a gas injector which mixes a gaseous fuel with the air supplied from the intake manifold; and a main fuel injection valve configured to inject a liquid fuel into the cylinder for combustion. At the time of switching the operation mode from one to the other between a gas mode and a diesel mode, an instant switching to the diesel mode is executed when the engine rotation number is determined to approach the upper limit value which leads to an emergency stop of the engine device.

A fuel mixing occurrence detection device is provided. The device includes a fuel-type identification unit that identifies a type of fuel injected into a vehicle by comparing a fuel pump drive RPM for achieving target fuel pressure with a predetermined reference value upon starting of the vehicle. A communication unit transmits a fuel mixing occurrence to an in-vehicle controller in response to determining that the fuel mixing has occurred.

A method for determining failure of an electromechanically actuated gas shut off valve includes sensing and recording a gas fuel rail pressure and a boost pressure from an air intake manifold at a first time after the dual fuel engine has been started. The method includes opening the gas shut off valve at a second time, holding the gas shut off valve in its open state, and then closing the gas shut off valve after a predetermined interval at a third time. The method includes comparing an actual gas rail pressure decay rate to a threshold gas rail pressure decay rate for the predetermined interval, and determining failure of the gas shut off valve when the actual gas rail pressure decay rate is less than the threshold gas rail pressure decay rate. Upon determining failure of the gas shut off valve, the method also includes initiating a mitigating action.