The present disclosure relates to a miniaturized fuel laboratory system having exterior dimensions enabling the system to be at least one of hand-holdable or contained on a component. The system makes use of a processor, a fuel inlet port for receiving a quantity of fuel to be used as a fuel test sample, and at least one fuel sensor in communication with the fuel inlet port for receiving the fuel test sample. The processor uses the information obtained by the fuel sensor to determine at least one characteristic of the fuel test sample.

A technique for fuel system protection for an internal combustion engine includes introducing a directly injected fuel into a combustion chamber through a direct fuel injector, introducing a fumigated fuel upstream of an intake valve, selectively operating the internal combustion engine with at least one of the directly injected fuel and the fumigated fuel, determining a temperature of the direct fuel injector as a first function of engine operating parameters, and performing a temperature mitigation technique when the temperature rises above a first predetermined value such that the temperature is maintained below a second predetermined value.

Method of supplying a spark-ignition internal combustion engine is provided. The method includes a mixing procedure, on board the vehicle, of methane and hydrogen and in which a ratio between methane and hydrogen is determined at least as a function of a methane quality. A spark ignition internal combustion engine includes at least one cylinder having an intake manifold and at least one methane and hydrogen injection device.

A method of operating a gas or dual fuel engine having a plurality of cylinders, includes monitoring a characteristic of each of the plurality of cylinders during operation of the gas or dual fuel engine. The method also includes detecting a pre-ignition condition associated with one or more cylinders of the plurality of cylinders based on the monitored characteristic. The method further includes reducing fuel supply to the one or more cylinders having the pre-ignition condition. The fuel supply to remaining cylinders of the plurality of cylinders is increased, to maintain a constant power output of the gas or dual fuel engine. The method further includes adjusting an amount of air supplied to each of the plurality of cylinders based on the increased amount of fuel supplied to the remaining cylinders, to maintain an air-to-fuel ratio within a desired range.

A method for controlling fuel flow in a multi fuel engine is disclosed. An input power for operating the multi fuel engine at a desired engine speed is determined and a fuel flow rate based on the input power, one or more fuel properties and a specified fuel substitution ratio for apportioning the plurality of fuels is determined. Also, a correction factor for the fuel flow rate based on a desired charge density, wherein the desired charge density is based at least on a relationship between an engine load and charge density is determined and a corrected fuel flow rate, based on the determined correction factor, is output to a corresponding actuator of a fluid flow control device for the one of the fuels to cause the corresponding actuator to provide the one of the plurality of fuels at the corrected fuel flow rate.

Systems and methods for controlling operation of dual fuel internal combustion engines in response to cylinder pressure based determinations are disclosed. The techniques control fueling contributions from a first fuel source and a second fuel source to achieve desired operational outcomes in response to the cylinder pressure based determinations.

Method of supplying a spark-ignition internal combustion engine is provided. The method includes a mixing procedure, on board the vehicle, of methane and hydrogen and in which a ratio between methane and hydrogen is determined at least as a function of a methane quality. A spark ignition internal combustion engine includes at least one cylinder having an intake manifold and at least one methane and hydrogen injection device.