Fan Assisted Scrubber

jasonvds · 13th April 2007, 11:44

Has anyone thought of building a fan assisted scrubber, ok so it might take some work to make sure that the fan lasted in a nice moist environment but could it cut down work of breathing??

**PhilSiswick** · 13th April 2007, 12:27

Quote: (Originally Posted by jasonvds)

Has anyone thought of building a fan assisted scrubber, ok so it might take some work to make sure that the fan lasted in a nice moist environment but could it cut down work of breathing??

Is this what you mean? http://www.rebreatherworld.com/home-...t=fan+scrubber

Cheers,

Boris The Builder · 13th April 2007, 12:31

An interesting concept but potentially another failure point. A point that would require the unit to run either with a back up fan or run efficiently without one. If the unit runs fine without one then no need to install one. Also could the scrubber clean effectively with the increased flow rate across the scrubber material?

Nick uk. · 13th April 2007, 12:34

If you want to cut down on WOB' you could just buy a YBOD......

Dutchy · 13th April 2007, 12:49

Quote: (Originally Posted by Boris The Builder)

An interesting concept but potentially another failure point. A point that would require the unit to run either with a back up fan or run efficiently without one. If the unit runs fine without one then no need to install one. Also could the scrubber clean effectively with the increased flow rate across the scrubber material?

No need to have an increased flow rate. Use your imagination. A small bore breathing hoses would be feasible resulting in a pendulum rebreather with hardly any dead space leading to a far better diver profile than the current designs at the same or better WOB.
And backup why? Don't you dive with bailout? Not everything has to be redundant. In the current design of your Rebreather the loop isn't either. It's just that statistically you'd have to bail out more often because of the added failure point.
Why not? Well mixing electric components water and oxygen doesn't seem so appealing to me but if there were a pneumatic design who knows?

Hmmm when I come to think o it an SCR could use the HP gas flow to drive the loop flow, maybe after all it is an option

**Freef** · 13th April 2007, 15:17

Just get an attractive young ladies phone number and make heavy breathing phone calls to her.

That increased my CV fitness a lot and reduced perceived WOB.

Led to a 6 month break from diving at Her Majesties Pleasure as well...

**Freef** · 13th April 2007, 15:23

How about a bungee linked to the divers left leg? It could compress the exhale lung to force up the gas pressure in the loop to make inhaling easier.

Advantages
-mechanical system so no electronic failure point.
-no electric gubbins in a rich O2 environment
-the faster you fin the easier to breathe-less stress in a current.

Disadvnatages
-if the bungee isn't black it's not techy enough for most people.
-might make a sound like bagpipes.

***ScubaDadMiami*** · 13th April 2007, 15:44

The goal is to maintain dwell time. Flowing gas will not have the same dwell time over the absorbent. So, you might wind up reducing the effort to rebreathe carbon dioxide.

Of course, you could then increase the size of the canister and add more scrubber, which would increase the weight of the unit, the overall distance that the gas will have to travel and the WOB, the last of which you are saying you are trying to avoid in the first place.

DanDunfee · 19th July 2007, 15:09

Fans in breathing loops were actually evaluated rather thoroughly back in the ~60-70s for use in veeery deep diving (1500 ft / 500 m +) where the veeery heavy WOB, just due to gas density, and the force required to move the gas, quickly drove working divers into pulmonary fatigue.

Biggest single issue was battery size and short duration due to energy drain. Maybe the advances in battery technology (Lithium etc.) could overcome this hurdle now...but

The advent of effectively articulated, compact, one-atmosphere, Jim Suits...and ROVs .... eliminated the need for such exhaustive, manned, open water diving.

13th April 2007, 11:44	#1 (permalink)
jasonvds New Member Current Rebreather/s: Other CCR Dolphin Ray Other SCR Other Rebreather/s: Other CCR Dolphin Ray Other SCR Join Date: Jan 2006 Location: Sydney, Australia Posts: 87	Fan Assisted Scrubber Has anyone thought of building a fan assisted scrubber, ok so it might take some work to make sure that the fan lasted in a nice moist environment but could it cut down work of breathing??
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13th April 2007, 12:27	#2 (permalink)
PhilSiswick WSKD 0001 Current Rebreather/s: Evolution Other Rebreather/s: Inspiration Vision Join Date: Apr 2006 Location: Oxford, UK Posts: 902	Re: Fan Assisted Scrubber Quote: (Originally Posted by jasonvds) Has anyone thought of building a fan assisted scrubber, ok so it might take some work to make sure that the fan lasted in a nice moist environment but could it cut down work of breathing?? Is this what you mean? http://www.rebreatherworld.com/home-...t=fan+scrubber Cheers, __________________ Phil No comment on open circuit... it's an evolutionary dead end not really worth discussing here. Dave Sutton, 2007 I have always felt that the dive I am on is not nearly important as the dives I plan to be on the rest of my life. Tom Rose, 2007 www.hugsac.org.uk
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13th April 2007, 12:31	#3 (permalink)
Boris The Builder New Member Current Rebreather/s: Ouroboros Other Rebreather/s: Join Date: Nov 2006 Location: UK Posts: 29	Re: Fan Assisted Scrubber An interesting concept but potentially another failure point. A point that would require the unit to run either with a back up fan or run efficiently without one. If the unit runs fine without one then no need to install one. Also could the scrubber clean effectively with the increased flow rate across the scrubber material? __________________ Boris The Builder Do not go where the path may lead, go instead where there is no path and leave a trail! - Ralph Waldo Emerson
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13th April 2007, 12:34	#4 (permalink)
Nick uk. Made in England. Current Rebreather/s: Inspiration Classic Azimuth Other Rebreather/s: Azimuth Join Date: Nov 2005 Location: Viale C.Colombo 75 Marina di Carrara. MS 54036 Italy Posts: 579	Re: Fan Assisted Scrubber If you want to cut down on WOB' you could just buy a YBOD...... __________________ If it aint broke....don't fix it, and if it is.............well......get another one! divechief2000@hotmail.com
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13th April 2007, 12:49	#5 (permalink)
Dutchy SK#007 Current Rebreather/s: Sport Kiss Other Rebreather/s: Join Date: Apr 2006 Location: Nieuwegein (The Netherlands) Posts: 717	Re: Fan Assisted Scrubber Quote: (Originally Posted by Boris The Builder) An interesting concept but potentially another failure point. A point that would require the unit to run either with a back up fan or run efficiently without one. If the unit runs fine without one then no need to install one. Also could the scrubber clean effectively with the increased flow rate across the scrubber material? No need to have an increased flow rate. Use your imagination. A small bore breathing hoses would be feasible resulting in a pendulum rebreather with hardly any dead space leading to a far better diver profile than the current designs at the same or better WOB. And backup why? Don't you dive with bailout? Not everything has to be redundant. In the current design of your Rebreather the loop isn't either. It's just that statistically you'd have to bail out more often because of the added failure point. Why not? Well mixing electric components water and oxygen doesn't seem so appealing to me but if there were a pneumatic design who knows? Hmmm when I come to think o it an SCR could use the HP gas flow to drive the loop flow, maybe after all it is an option __________________ = This post is environmentally friendly. It is composed of 100% recycled electrons only. = SK #007 Last edited by Dutchy : 13th April 2007 at 14:46. Reason: added SCR drive gas option
(Online)

13th April 2007, 15:17	#6 (permalink)
Freef Custom Title Disallowed! Current Rebreather/s: Dolphin Other Rebreather/s: Dolphin Join Date: Jan 2006 Location: Land of the Freef, UK. Posts: 1,356	Re: Fan Assisted Scrubber Just get an attractive young ladies phone number and make heavy breathing phone calls to her. That increased my CV fitness a lot and reduced perceived WOB. Led to a 6 month break from diving at Her Majesties Pleasure as well... __________________ David. Currently owner of two differently sized ankles.
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13th April 2007, 15:23	#7 (permalink)
Freef Custom Title Disallowed! Current Rebreather/s: Dolphin Other Rebreather/s: Dolphin Join Date: Jan 2006 Location: Land of the Freef, UK. Posts: 1,356	Re: Fan Assisted Scrubber How about a bungee linked to the divers left leg? It could compress the exhale lung to force up the gas pressure in the loop to make inhaling easier. Advantages -mechanical system so no electronic failure point. -no electric gubbins in a rich O2 environment -the faster you fin the easier to breathe-less stress in a current. Disadvnatages -if the bungee isn't black it's not techy enough for most people. -might make a sound like bagpipes. __________________ David. Currently owner of two differently sized ankles.
(Offline)

13th April 2007, 15:44	#8 (permalink)
*ScubaDadMiami* Moderator Current Rebreather/s: Optima Other Rebreather/s: Join Date: Sep 2005 Location: Florida, USA Posts: 2,025	Re: Fan Assisted Scrubber The goal is to maintain dwell time. Flowing gas will not have the same dwell time over the absorbent. So, you might wind up reducing the effort to rebreathe carbon dioxide. Of course, you could then increase the size of the canister and add more scrubber, which would increase the weight of the unit, the overall distance that the gas will have to travel and the WOB, the last of which you are saying you are trying to avoid in the first place. __________________ Howard Packer IANTD CCR Instructor Miami Beach, Florida CCRDiveTraining.com
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19th July 2007, 15:09	#9 (permalink)
DanDunfee Custom Title Allowed! Current Rebreather/s: Other CCR Other SCR Home Build Other Rebreather/s: Not Bought Yet Other CCR Other SCR Home Build Join Date: Sep 2005 Location: Virginia, USA Posts: 204	Re: Fan Assisted Scrubber Fans in breathing loops were actually evaluated rather thoroughly back in the ~60-70s for use in veeery deep diving (1500 ft / 500 m +) where the veeery heavy WOB, just due to gas density, and the force required to move the gas, quickly drove working divers into pulmonary fatigue. Biggest single issue was battery size and short duration due to energy drain. Maybe the advances in battery technology (Lithium etc.) could overcome this hurdle now...but The advent of effectively articulated, compact, one-atmosphere, Jim Suits...and ROVs .... eliminated the need for such exhaustive, manned, open water diving. __________________ There are 'Bold' divers and old divers, but NO old, ' Bold ' divers
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