Fuel Tank Bladder With Phase-Change Heat Storage for Vapor Pressure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle fuel tanks face issues with pressure build-up due to fuel vapor generation caused by temperature fluctuations, which can damage the tank or pose explosion risks, and prior solutions like inflatable bladders reduce tank capacity and complicate manufacturing.
Innovation Solution
A fuel storage system combining an inflatable bladder with heat storage members using phase-change materials to absorb heat and limit temperature rise, allowing the bladder to be smaller and reducing vapor pressure without compromising tank capacity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a large-volume inflatable bladder is placed inside the fuel tank to reduce fuel vapor pressure, then the pressure control effectiveness is improved, but the useful tank capacity is reduced and the manufacturing complexity increases
Solution Approach 1:
The invention changes the approach from using a large-volume bladder to a smaller heat storage member by changing the control parameter from mechanical volume displacement to thermal energy management. The heat storage member with phase-change material absorbs heat during phase transition, indirectly controlling fuel vapor pressure by maintaining lower fuel temperature, thus achieving pressure control with minimal volume occupation in the tank.
Solution Approach 2:
The heat storage member acts as an intermediary between the fuel and the bladder. Instead of the bladder directly controlling pressure through volume displacement, the heat storage member first absorbs heat from the fuel, preventing vapor generation, which then allows the bladder to operate with much smaller volume while achieving the same pressure control effect.
2Reliability
If a large-volume inflatable bladder is placed inside the fuel tank to reduce fuel vapor pressure, then the pressure control effectiveness is improved, but the device complexity and manufacturing difficulty increase
Solution Approach 1:
The invention segments the pressure control function into two independent components: a heat storage member for thermal management and a bladder for pressure regulation. This segmentation allows each component to be optimized independently - the heat storage member can be a simple container with phase-change material, and the bladder can be smaller and easier to install, reducing overall manufacturing complexity compared to a single large-volume bladder system.
3Temperature
If a heat storage member with phase-change material is added to the fuel tank, then the fuel temperature control is improved and vapor pressure is reduced, but the device complexity increases
Solution Approach 1:
The invention merges the heat storage member with the existing bladder system, where the heat storage member is positioned inside or adjacent to the bladder. This combination allows the heat storage member to benefit from the bladder's insulation properties while the bladder benefits from the heat storage member's temperature control, achieving synergistic effect without proportionally increasing complexity.
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
The combined system effectively manages fuel vapor pressure by minimizing bladder volume requirements and ensuring consistent fuel temperature, enhancing tank capacity and simplifying manufacturing while maintaining pressure control.
Implementation Method 1
at least one heat storage member, extending inside the tank, comprising a phase-change material with a melting point between 18° and 40° C.
Implementation Method 2
The at least one heat storage member can absorb heat, particularly when the fuel has a temperature close to the melting point of the phase-change material. Since the fusion reaction is endothermic, it consumes heat from the fuel.
Data Source
AI summary
A fuel storage system may be configured for a vehicle and may include a fuel tank, at least one inflatable bladder extending inside the tank, and at least one heat storage member, extending inside the tank, comprising a phase change material having a melting point in a range of from 18 to 40° C. The heat storage member may be attached to a bottom wall of the tank and/or attached to the bladder. The system may include several heat storage members.