Pressure Vessel Valve Control for Safe Pressure Equalization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Pressure vessel systems in hydrogen-powered vehicles face issues with valve damage due to increased pressure differences, leading to costly and space-intensive solutions to meet regulatory requirements for outlet pressure being at least 50% of inlet pressure.
Innovation Solution
A pressure vessel system with a control unit that regulates the valve operation based on actual pressure differences, using a pilot-controlled valve and a bypass valve to manage pressure equalization, and a pressure relief device to prevent excessive pressure differences, allowing for lightweight and space-efficient designs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the tank shut-off valve is designed for a maximum operating pressure twice as high as the nominal operating pressure, then the valve can withstand increased pressure differences and prevent damage, but the valve becomes relatively expensive and requires a relatively large amount of structural space
Solution Approach 1:
The control unit performs preliminary actions by detecting the pressure difference across the valve before opening and actively managing pressure downstream through the replenishment line or bypass valve. This prevents the harmful situation of opening a valve with excessive pressure difference, thereby protecting the valve without requiring it to be designed for twice the nominal pressure
Solution Approach 2:
The patent introduces intermediary elements (replenishment line, bypass valve, control unit) that mediate between the high-pressure upstream side and the downstream side. These intermediaries actively manage pressure differences, allowing the use of lighter, more compact valves that wouldn't otherwise withstand the pressure differential
2Reliability
If the tank shut-off valve is designed for a maximum operating pressure twice as high as the nominal operating pressure, then the valve can withstand increased pressure differences and prevent damage, but the valve becomes relatively expensive
Solution Approach 1:
The control unit performs preliminary detection of pressure difference and active pressure management before valve opening, preventing damage scenarios and allowing the use of less expensive, lighter-duty valves that wouldn't otherwise survive excessive pressure differentials
Solution Approach 2:
Intermediary systems (control unit, replenishment line, bypass valve) are introduced to manage pressure differences, enabling the use of more cost-effective valves that don't require the expensive design margin of twice-nominal-pressure capability
3Productivity
If fuel continues to be extracted downstream of the closed tank shut-off valve, then the pressure downstream decreases and the pressure difference increases, but this creates a situation where the valve outlet pressure would be less than 50% of inlet pressure upon opening
Solution Approach 1:
The control unit continuously monitors pressure downstream of the valve and uses this feedback information to detect when pressure difference exceeds safe limits. This feedback mechanism prevents the harmful condition of opening a valve with excessive pressure difference, thereby maintaining valve operation safety while allowing continuous fuel extraction
Solution Approach 2:
The control unit takes preliminary action by detecting excessive pressure difference before valve opening and actively managing downstream pressure through the replenishment line or bypass valve, preventing the situation where outlet pressure would be less than 50% of inlet pressure
Data Source
AI summary
A method for operating a valve of a pressure vessel system includes determining an actual pressure difference between an inlet pressure at an inlet of the valve and an outlet pressure at an outlet of the valve, and enabling the valve if the actual pressure difference is lower than or equal to a maximum admissible pressure difference of the valve.