Ullage Pressure Regulator for Hypersonic Fuel Tanks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-speed flight vehicles face challenges in maintaining accurate fuel delivery due to pressure fluctuations in fuel tanks, as existing pressure regulators are imprecise at high pressures and unable to handle large pressure drops, compromising engine performance.
Innovation Solution
A smart pressure regulator that uses an on-board controller to meter gaseous pressurant into the fuel tank ullage, adjusting the metering valve based on pressure feedback to maintain internal tank pressure within narrow limits, capable of operating across a pressure drop of approximately 5,000 psia.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If mechanical regulators are used to stabilize fuel tank pressure, then pressure stabilization is achieved, but precision deteriorates due to large frictional forces and hysteresis at high pressure conditions
Solution Approach 1:
The patent replaces the mechanical regulator with an electronic regulator that uses an electronic actuator (solenoid) instead of mechanical springs and pistons. This substitution eliminates frictional forces and hysteresis that degrade precision at high pressure conditions, while maintaining pressure stabilization capability through electronic control of the metering orifice.
Solution Approach 2:
The patent implements a feedback control system where a pressure sensor continuously monitors the fuel tank pressure and feeds this information to a controller. The controller adjusts the electronic actuator based on the pressure deviation from the set point, enabling precise pressure control by constantly correcting for deviations, thus overcoming the precision limitations of mechanical regulators.
2Adaptability or versatility
If multiple stages of mechanical regulators are used to handle large pressure range applications, then pressure range coverage is improved, but device complexity, size and weight increase
Solution Approach 1:
The patent uses an electronic actuator controlled by a microprocessor-based controller to handle the entire pressure range (0-5000 psia) in a single stage, eliminating the need for multiple mechanical stages. The electronic system can precisely control the metering orifice opening across any pressure differential, reducing device complexity while maintaining full pressure range coverage.
Solution Approach 2:
The patent employs electronic control to dynamically adjust the metering orifice opening based on real-time pressure feedback, allowing the single-stage regulator to adapt to any pressure range. This parameter-based control (electronic duty cycle adjustment) replaces the need for multiple fixed mechanical stages, reducing complexity while maintaining versatility.
3Stress or pressure
If conventional regulators are used to handle large pressure drop (5000 psia), then pressure drop capability is improved, but accuracy deteriorates
Solution Approach 1:
The patent replaces conventional mechanical regulators with an electronic regulator that uses a solenoid actuator to control the metering orifice. This electronic control system can maintain accurate pressure regulation even at extreme pressure drops of 5000 psia by electronically adjusting the orifice opening based on feedback, overcoming the accuracy limitations of mechanical regulators at such high pressure differentials.
Solution Approach 2:
The patent implements a closed-loop feedback system with a pressure sensor that continuously monitors tank pressure and feeds this to the controller. The controller adjusts the electronic actuator in real-time based on the pressure deviation, maintaining accurate pressure control even under large pressure drops (5000 psia) where mechanical regulators would fail to maintain precision.
4Measurement precision
If electronic regulators are used to provide accurate control at low flow conditions, then measurement precision is improved, but reliability deteriorates at high flow rates
Solution Approach 1:
The patent uses an electronic actuator (solenoid) that can reliably operate across the full range of flow conditions. The electronic control system with feedback can maintain precision at low flows while the robust electronic actuator and orifice design ensure reliability at high flows, overcoming the reliability limitations of conventional electronic regulators at high flow rates through proper hardware selection and control strategy.
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 regulator maintains internal tank pressure within ±1.5% of the set point, ensuring precise fuel delivery and engine performance by accurately controlling the flow of pressurized media using pulse-width modulating control in a closed-loop system.
Implementation Method 1
The controller sends the input signal to a coil within the body to position the metering valve with respect to the metering orifice accordingly
Data Source
AI summary
A system for maintaining pressure in the liquid fuel tank of a high-speed flight vehicle, such as a hypersonic flight, scramjet powered air and space vehicle, manages tank ullage using a pressure regulator coupled to the fuel tank that supplies pressurized gaseous media into the fuel tank ullage based on the internal pressure of the tank. The regulator has an on-board controller that processes tank pressure input to deliver a pulse-width modulated input signal to the coil of the on-board solenoid metering assembly. Energizing the coil drives the metering valve open against spring force. The metering assembly is contained in a removable cartridge that has a floating valve guide that is held stationary by bias of the spring against the metering valve. The metering valve has a separate valve seat that mates with the metering orifice of a flow nozzle. The valve seat can have higher compressibility than a clapper part of the valve to effect a better seal, with its compression being controlled by contact of the clapper with a rigid stop surface of the flow nozzle.