Abstract: A system and method for detecting pressure deviation of a first fluid in an engine is disclosed. The method may comprise calculating, for each of a plurality of measurements, a delta between an actual first fluid pressure and a target pressure, summing each delta obtained from the calculating, and determining pressure deviation of the first fluid based on a cumulative sum of the deltas. In an embodiment, the first fluid may be natural gas.

Abstract: A compression ignition engine is fueled from common rail fuel injectors that predominately inject natural gas fuel that is compression ignited with a small pilot injection of liquid diesel fuel. Before and after a rapid load loss transient, the liquid and gaseous rail pressures are controlled toward respective pressures based upon engine speed and load. During the transient, the liquid rail pressure is controlled relative to the gas rail pressure in order to maintain the liquid rail pressure greater than the gas pressure during the transient to avoid migration gaseous fuel into the liquid fuel side of the system.

Abstract: A system and method for detecting pressure deviation of a first fluid in an engine is disclosed. The method may comprise calculating, for each of a plurality of measurements, a delta between an actual first fluid pressure and a target pressure, summing each delta obtained from the calculating, and determining pressure deviation of the first fluid based on a cumulative sum of the deltas. In an embodiment, the first fluid may be natural gas.

Abstract: A compression ignition engine is fueled from common rail fuel injectors that predominately inject natural gas fuel that is compression ignited with a small pilot injection of liquid diesel fuel. Before and after a rapid fueling increase transient, the liquid and gaseous rail pressures are controlled toward respective pressures based upon engine speed and load. During the transient, the liquid rail pressure is controlled toward an elevated liquid pressure in order to cause a surge in the supply of gaseous fuel to the gaseous fuel common rail to proactively satisfy the increased gaseous fuel injection rate while obviating a substantial pressure deficit in the gaseous fuel common rail.

Abstract: A system, related method and computer program product are disclosed for controlling fuel mass of CNG received by an engine. The system may comprise a heat exchanger configured to receive CLNG and supply coolant and to output CNG and return coolant, an injector configured to inject CNG into the engine, a gas line between the injector and heat exchanger, a control valve configured to receive return coolant from the heat exchanger and to change the amount of return coolant flowing through control valve, and a controller connected to the control valve. The gas line may be configured to carry CNG from the heat exchanger to the injector. The controller may be configured to maintain a Gas Line Temperature within an operating range by adjusting the amount of return coolant flowing through the control valve based, at least in part, on the Gas Line Temperature and a Target Return Coolant Temperature.

Abstract: A method of detecting leakage of a fluid from a tank is disclosed. The method may include determining cumulative commanded fluid consumption of the fluid in the tank over a selected time period, determining an actual change of a volume of the fluid in the tank over the selected time period, and comparing the cumulative commanded fluid consumption to the actual change of volume of the fluid. The method may further include producing a leak warning upon the actual change of volume of the fluid over the selected time period exceeding the cumulative commanded fluid consumption over the selected time period plus a threshold value.

Abstract: A dual fuel common rail system may be operated in a regular mode in which a relatively large charge of gaseous fuel is ignited by compression igniting a relatively small injection quantity of liquid diesel fuel. The dual fuel system may be operated in a single fuel limp home mode in which liquid diesel fuel is injected at higher pressures. When transitioning from the single fuel limp home mode to the dual fuel regular mode, accumulated leaked liquid fuel in the gaseous nozzle chamber of each fuel injector is purged and burned in the respective engine cylinder.

Abstract: A compression ignition engine is fueled from common rail fuel injectors that predominately inject natural gas fuel that is compression ignited with a small pilot injection of liquid diesel fuel. Prior to servicing the engine, a service tool may establish a communication link with an electronic controller that controls operation of the engine. Pressure information for a gaseous fuel common rail and a liquid fuel common rail are displayed with the service tool, when the engine is stopped, in order to determine whether the rails are completely depressurized indicating that it is then o.k. to perform servicing tasks.

Abstract: A method of detecting leakage of a fluid from a tank is disclosed. The method may include determining cumulative commanded fluid consumption of the fluid in the tank over a selected time period, determining an actual change of a volume of the fluid in the tank over the selected time period, and comparing the cumulative commanded fluid consumption to the actual change of volume of the fluid. The method may further include producing a leak warning upon the actual change of volume of the fluid over the selected time period exceeding the cumulative commanded fluid consumption over the selected time period plus a threshold value.

Abstract: A compression ignition engine is fueled from common rail fuel injectors that predominately inject natural gas fuel that is compression ignited with a small pilot injection of liquid diesel fuel. Before and after a rapid fueling increase transient, the liquid and gaseous rail pressures are controlled toward respective pressures based upon engine speed and load. During the transient, the liquid rail pressure is controlled toward an elevated liquid pressure in order to cause a surge in the supply of gaseous fuel to the gaseous fuel common rail to proactively satisfy the increased gaseous fuel injection rate while obviating a substantial pressure deficit in the gaseous fuel common rail.

Abstract: A compression ignition engine is fueled from common rail fuel injectors that predominately inject natural gas fuel that is compression ignited with a small pilot injection of liquid diesel fuel. Before and after a rapid load loss transient, the liquid and gaseous rail pressures are controlled toward respective pressures based upon engine speed and load. During the transient, the liquid rail pressure is controlled relative to the gas rail pressure in order to maintain the liquid rail pressure greater than the gas pressure during the transient to avoid migration gaseous fuel into the liquid fuel side of the system.

Abstract: Methods and systems for detecting leakage of a liquid fuel into a gas fuel rail of a dual-fuel system for an internal combustion engine are disclosed. The methods and systems include sending an injection signal from a controller to a fuel injector and subsequently injecting gas fuel and liquid fuel into a cylinder for combustion. A pressure in the gas rail detects the pressure in the gas rail over a pre-determined time period after the injection event. A controller measures pressure fluctuations in the gas rail over a pre-determined time period after the injection event. If the pressure in the gas rail fluctuates by more than the pre-determined amount, the controller is programmed to take at least one mitigating action to prevent or limit damage to the engine.

Abstract: A system, related method and computer program product are disclosed for controlling fuel mass of CNG received by an engine. The system may comprise a heat exchanger configured to receive CLNG and supply coolant and to output CNG and return coolant, an injector configured to inject CNG into the engine, a gas line between the injector and heat exchanger, a control valve configured to receive return coolant from the heat exchanger and to change the amount of return coolant flowing through control valve, and a controller connected to the control valve. The gas line may be configured to carry CNG from the heat exchanger to the injector. The controller may be configured to maintain a Gas Line Temperature within an operating range by adjusting the amount of return coolant flowing through the control valve based, at least in part, on the Gas Line Temperature and a Target Return Coolant Temperature.

Abstract: A dual fuel common rail system may be operated in a regular mode in which a relatively large charge of gaseous fuel is ignited by compression igniting a relatively small injection quantity of liquid diesel fuel. The dual fuel system may be operated in a single fuel limp home mode in which liquid diesel fuel is injected at higher pressures. When transitioning from the single fuel limp home mode to the dual fuel regular mode, accumulated leaked liquid fuel in the gaseous nozzle chamber of each fuel injector is purged and burned in the respective engine cylinder.