Fuel Tank Relief Vent Crossbar Positioning for Laminar Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fuel storage tank relief vents experience reduced flow rates due to turbulence caused by centrally located crossbars, failing to meet high flow rate requirements for emergency situations and UL certification standards.
Innovation Solution
A relief vent assembly with a crossbar positioned at the distal margin of the vent body, maintaining a smooth flow path and preventing premature turbulence, ensuring laminar flow and increased discharge rates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a crossbar is centrally located in the vent body to support the lid, then the lid is properly supported and the vent structure is stable, but turbulence is introduced to the fluid flow causing reduced flow rate
Solution Approach 1:
The crossbar is extracted from the central location and repositioned to the distal margin of the vent body, removing it from the fluid flow path. This eliminates the turbulence-causing obstruction while preserving the lid support function, thereby resolving the contradiction between structural stability and flow rate.
Solution Approach 2:
The crossbar position is changed from a central axial location to a distal marginal location, effectively moving it to a different spatial dimension relative to the flow path. This repositioning allows the crossbar to support the lid without interfering with the laminar flow of pressurized fluid through the vent chamber.
2Productivity
If the vent assembly allows rapid discharge of pressurized fluid, then emergency pressure relief is achieved, but foreign matter may enter the tank through the open vent passage
Solution Approach 1:
A screen is introduced as an intermediary element within the vent passage, positioned to allow rapid fluid discharge while blocking foreign matter. This mediator enables the vent to achieve both high productivity in emergency pressure relief and protection against contaminant intrusion.
3Object-affected harmful factors
If a gravity closing vent is used to prevent foreign matter entry, then the tank is protected from contaminants, but the vent lid must be in vertical orientation limiting design options
Solution Approach 1:
The vent lid is designed with a spring mechanism that enables dynamic operation - remaining closed to prevent contaminants during normal conditions, and opening rapidly under pressure. This dynamic design replaces the static gravity-dependent mechanism, providing placement flexibility while maintaining contaminant protection.
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 solution achieves a high flow rate of 110,000 cubic feet per hour at 2.5 psi, meeting UL certification standards and ensuring rapid evacuation of pressurized fluid during emergencies.
Implementation Method 1
The relief vent assembly provides a flow path through a chamber of the vent body that is substantially smooth and unencumbered, ensuring that the flow of pressurized fluid remains laminar throughout approximately the entire path.
Data Source
AI summary
A relief vent assembly for a fuel storage tank includes a vent body defining a chamber to provide a substantially axially smooth and unencumbered path of flow for pressurized fluid to vent out from the tank. Such a path of flow allows the pressurized fluid to remain laminar throughout approximately the entire path through the chamber, maintaining a high flow rate. The vent assembly includes a crossbar that supports the rod of a lid that covers a distal margin of the vent body. The crossbar is disposed substantially at the distal margin of the vent body to prevent any premature turbulent flow of the pressurized fluid, which would slow the flow rate. A widening tapered bore of the chamber increases the flow area and serves to offset the area occupied by the crossbar.