|
Rubicon Research Repository >
Rubicon Foundation Archive >
UHMS Meeting Abstracts >
Please use this identifier to cite or link to this item:
http://archive.rubicon-foundation.org/1227
|
| Title: | AIR AMPLIFIER REPLACES ELECTRIC BLOWER IN OXYGEN EDUCTION SYSTEM TO ENHANCE FIRE SAFETY |
| Authors: | Natoli, MJ |
| Keywords: | multiplace
model
dry
hyperbaric
air
chamber
fire safety
hyperbaric chamber
air amplifier
oxygen eduction system
ELECTRICAL |
| Issue Date: | 2002 |
| Abstract: | Goal: Replace the electric blower in the oxygen eduction system of a multiplace hyperbaric chamber complex with a device that decreases fire risk. Objective: Demonstrate the advantages of replacing an electrically powered device with an air operated device with equal capability. Background: The existing oxygen eduction system consisted of a pipe manifold which collected oxygen enriched gas from the overboard dump systems of five human-rated hyperbaric chambers and exhausted it from the building via an electric squirrel cage blower. The capability of the eduction system was set by the limit of simultaneous oxygen administration (14 single pass head tents at 3ATA) at ~2520 L min-1 (90 scfm). Use of 30 year old electric fan technology to draw the oxygen enriched gas from the chambers to the building exhaust was questioned after such a fan burned at its electrical connection. An air amplifier is an air powered tubular device that creates a suction at its input and an amplified output flow. The device utilizes the Coanda Effect, a basic principle of fluidics, to create increased air velocity due to low pressure created at the center of the specially designed tube. Air amplifiers have no moving parts, require no electricity and are maintenance-free. Supply air must be dry and filtered and pressure can be regulated to decrease outlet flow. Both the vacuum and discharge ends of the air amplifier can be ducted, making it ideal for drawing fresh air or gas transfer and dilution. Methods: The chamber overboard dump systems were designed to collect excess gas from oxygen delivery devices used inside the chambers (single pass and recirculating head tents, masks, and ventilators) and dump the excess outside the chamber through back pressure regulators. Each dump system was connected outside the chamber via 2.5 cm (1 in) internal diameter (ID) pipe to a 5.1 cm (2 in) ID eduction manifold. The manifold was configured as a "Y", open to room air at its origins and connected to the building exhaust at its termination. An Exair Super Air Amplifier (model 120222) was purchased and installed with suction at the end of the eduction manifold. Its outlet was connected to the 61 cm2 (4 ft2) exhaust duct exiting the building. The air amplifier provided enough suction to draw the oxygen from all of the overboard dump systems and entrain air into the origins of the manifold. At 20 psi supply pressure (relative to normal atmospheric pressure), the air requirement was 1557 L min-1 (5.5 scfm) and the draw on the eduction pipe from the chambers was 3240 L min-1 (114.5 scfm.) Verification of suction at the manifold origins was made with a vacuum style differential pressure gauge (Magnehelic, model 2310.) Results and Conclusion: The air amplifier is able to maintain an adequate suction to transfer oxygen enriched air from the chamber overboard dump system to the building exhaust duct. The suction required for safe operation of the eduction system is maintained with low compressed air requirement. Replacing an electrically powered source from the oxygen eduction system removes a fire risk from the chamber facility. Abstract 12 |
| Description: | Undersea and Hyperbaric Medical Society, Inc. (http://www.uhms.org ) |
| URI: | http://archive.rubicon-foundation.org/1227 |
| Appears in Collections: | UHMS Meeting Abstracts
|
All items in DSpace are protected by copyright, with all rights reserved.
|
