Gas Shut Off Valve Failure Detection in Dual Fuel Engines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining the failure of a shut off valve in a dual fuel engine, such as those described in U.S. Pat. No. 6,467,466, are not applicable when the engine is in operation, as they require engine shutdown for gas leakage detection, and do not effectively assess valve failure when the valve remains in a partially closed position.
Innovation Solution
A method and control system that utilize sensors to record gas fuel rail pressure and boost pressure, then compare the actual gas rail pressure decay rate to a threshold rate after opening and closing the shut off valve, determining failure if the decay rate is less than the threshold, and initiating mitigating actions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If gas leakage detection is performed using existing methods, then leakage can be detected, but the engine operation must be stopped which reduces productivity
Solution Approach 1:
The system performs preliminary actions by continuously monitoring gas rail pressure and boost pressure during normal engine operation, calculating pressure decay rates in real-time to detect valve failures without requiring engine shutdown. This allows the detection mechanism to be prepared and active before any failure occurs, enabling immediate detection while maintaining productivity.
Solution Approach 2:
The patent replaces the mechanical/manual engine shutdown approach with an electronic sensing and calculation system that uses pressure sensors, a controller, and algorithms to automatically detect valve failures. This substitution of mechanical interruption with electronic monitoring enables continuous operation while maintaining detection capability.
2Ease of operation
If the shut off valve is commanded to close but remains in partially closed position, then the valve appears to be functioning, but gas continues to leak into the fuel rail causing undesirable engine operation
Solution Approach 1:
The system implements feedback by continuously monitoring the gas rail pressure before and after valve closure commands, calculating the pressure decay rate, and comparing it against expected values. This feedback loop provides real-time information about actual valve performance, revealing when valves fail to seal properly even though they receive closure commands, thereby detecting reliability issues that simple position monitoring would miss.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables real-time detection of shut off valve failure in a dual fuel engine while it is operating, preventing undesirable engine operation and allowing for immediate corrective actions.
Implementation Method 1
sensing and recording a gas fuel rail pressure at a first time using a first sensor in communication with the gas fuel rail
Implementation Method 2
sensing and recording a boost pressure at the first time using a second sensor in communication with an intake air manifold
Implementation Method 3
An electromechanically actuated shut off valve may be used in a fuel rail of a dual fuel engine to selectively allow a flow of charge, for example, gas into the fuel rail downstream of the shut off valve
Data Source
AI summary
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.