Aerated Foam Nozzle Stream Shaping for Large Tank Fire Coverage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fixed systems for extinguishing fires in large industrial tanks are costly, unreliable, and ineffective, particularly for full surface liquid tank fires, as they require numerous foam chambers and pose risks to personnel due to the need for manual hose deployment and limited foam run distances.
Innovation Solution
Development of a fixed system using aerated foam nozzles with a stream shaper that projects a focused stream of foam up to 6.10 m away with a 2-to-1 to 8-to-1 expansion ratio, capable of covering larger tank diameters with fewer units, and incorporating a semi-fixed Point and Shoot system for rim seal fires and Ambush system for full surface fires, which includes a center pointing nozzle for enhanced coverage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If traditional foam chambers are used to extinguish fires in large industrial tanks, then foam can be applied to the tank surface, but the foam run distance is limited and numerous units are required, increasing system complexity and cost
Solution Approach 1:
The patent changes the physical parameters of foam discharge by using aerated foam with 2-to-1 to 8-to-1 expansion ratio projected at high velocity (up to 6.10 m distance) compared to traditional gravity-dependent foam chambers. This parameter change enables fewer units to cover larger tank surfaces.
Solution Approach 2:
The invention employs hydraulic projection of aerated foam through nozzles with stream shapers, utilizing fluid dynamics to achieve focused streams that travel farther and cover larger areas. This replaces the passive gravity-based foam chamber approach with active hydraulic projection.
2Ease of operation
If manual hose deployment is used in traditional fixed systems, then personnel can deploy foam equipment, but personnel safety is compromised due to exposure to fire hazards and hot surfaces
Solution Approach 1:
The fixed system with aerated foam nozzles is designed to operate automatically or with minimal personnel intervention. The system self-deploys foam through fixed piping and nozzle assemblies that remain in place, eliminating the need for personnel to manually handle hoses near fire hazards.
Solution Approach 2:
The fixed nozzle system is pre-installed and pre-positioned on the tank structure, with foam lines already routed to optimal discharge locations. This preliminary setup eliminates the need for manual hose deployment during emergency situations, protecting personnel from exposure.
3Quantity of substance
If traditional foam projection systems are used, then foam can be discharged onto the tank surface, but the foam stream is dispersed and coverage efficiency is reduced
Solution Approach 1:
The patent optimizes foam discharge parameters by controlling expansion ratio (2-to-1 to 8-to-1) and projection velocity to achieve a focused stream. This parameter control ensures that foam volume is concentrated in a directed stream rather than dispersed, improving coverage efficiency.
Solution Approach 2:
The stream shaper acts as an intermediary component between the aerated foam source and the tank surface. It focuses and directs the foam stream, maintaining coherence and preventing dispersion, thereby improving the efficiency of foam application.
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 system achieves effective and rapid foam coverage of larger tank surfaces, reducing the number of units required and minimizing personnel risk by projecting foam farther and faster than traditional systems, ensuring efficient extinguishment of rim seal and full surface fires in tanks up to 400 feet in diameter.
Implementation Method 1
aerated foam nozzles with a stream shaper that projects a focused stream of foam up to 6.10 m away with a 2-to-1 to 8-to-1 expansion ratio
Implementation Method 2
projects a focused stream of foam up to 6.10 m away
Data Source
Figure 1~2
Figure 6~7
Figure 8A~8E
AI summary
A wand having at least one aerated foam projecting nozzle for projecting foam in a substantially focused stream and a roughly horizontal direction around an inside tank wall surface including: a first ambient air aeration chamber located upstream of, proximate to and in fluid communication with an at least one aerated foam projecting nozzle, the nozzle having at least four fins in a tip portion, the fins having a longitudinal dimension greater than a radial dimension and terminating substantially flush with a nozzle tip discharge orifice; the chamber structured together with the nozzle to project at least 100 gpm, at 100 psi, of aerated foam having an expansion of between 2-to-1 to 8-to-1; the nozzle and chamber attached to a riser for communicating water and foam concentrate; and said at least one nozzle and riser structured in combination for attachment to a tank wall of an at least 100 feet diameter tank such that the nozzle projects foam in a roughly horizontal direction around an interior top tank wall surface.