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nonaeroterraqueous

Heat Exchange Masks

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I was camping in the off season, the cold time of the year, all wrapped up in my minus whatever degree mummy bag, freezing my butt off, and I realized that I wasn't actually losing any significant heat through the bag. It occurred to me that the lungs represent a huge exposed surface area with constant windchill and high humidity, and that surface cannot be covered with a blanket to insulate it from the outside air. If you could protect it from the air you'd die. So, you reach a point where no added layer of clothing is enough to make you warm.

 

I remember learning about a principle called countercurrent exchange, which has a Wikipedia page. Bacically, by having the outflowing air running in the opposite direction to the inflowing air, intimately close, with a heat-conductive layer between them, you can have an exchange of air with minimal loss of heat.

100px-Countercurrent_exchange.png

It would work best with one tube inside another, or a lot of narrow tubes for the inlet, with the outlet air running along the spaces between the tubes. I did some online searching and found a couple of related patents. They made mention of a serious problem with this application. Although it works well for bringing fresh air into homes, human breath is so humid that such a system would generate enormous amounts of condensation, which, in cold weather, results in clogging the device with ice. Instead of having the two currents run beside each other, the inventors had the air run back and forth along the same path, so that the air did a reuptake of the moisture on the way back in. Then, the whole countercurrent mechanism gets reduced to a simple principle of having a heat sink to grab the heat on the way out and release the heat on the way in, whether that's by passing the air through copper tubing, or weaving copper threads into a face mask. It's counter-intuitive, but it means that, while we normally protect ourselves against heat loss by covering ourselves with non-conductive material, the key to preserving breath heat requires conductive material.

 

31sfA7SazFL._AA160_.jpg The most common attempt at insulating breath seems to be the balaclava, which amounts to stifling your breath with a cloth. As much as you succeed in getting the breath through the cloth, the heat succeeds in getting out of your body.

 

41V28MsB7jL._SX425_.jpg The Polarwrap seems to use heat-conductive tubing, as far as I can tell.

 

31dtE59qvpL._AA160_.jpg Then there's a product aimed at sufferers of COPD, called the Airguard, which seems to be, in a nutshell, an SOS pad (copper fibers) sewn in between layers of fabric.

 

41ou4JuWeDL._AA160_.jpg The least helpful design I've found is one that traps a cup of stale exhaled air and mixes it into the inhalation. Then, you're stuck with the same problem as the balaclava: the more you succeed in breathing, the more you succeed in losing heat.

 

It does strike me as interesting how little there is out there in the way of heat exchange masks, considering all the money and material geared toward keeping our outsides warm. It's like washing only half of the car, or painting only half of the room. I'd like to know if anyone has any experience with heat exchange masks, and if there are other products out there that I haven't heard of yet. I haven't bought one of these things, yet, though I'm probably going to try it eventually, if winter ever gets going again.

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We've tried everything from simple balaclavas, neoprene shields (mad dog face for Cerberus) and polar wraps for hunting.

- There's no way we'd try the Talus (nasty Vader rubber cup gizmo).

 

On the Harleys, where air is flying in your face, all worked fine at staying warm and not having to do the choke/gasp (goldfish outta the bowl) thing for freezing air, but CJ still had her glasses fog up.

- Our Panoptyx motorcycle glasses have foam inserts so air doesn't tear your eye, so must be a vent area where warm, damp air's entering from a not fully sealed mask.

 

None seemed to keep us warmer still hunting longer than an hour.

Even the polar wrap (from Cabelas), helped breathing very cold air, but left your face soaked after a time. Wet face and freezing air not a good mix.

 

Hiking, CJ couldn't see with any of them (glasses fogging). Smaller mask might work, but (at least at the time) only two sizes to choose from sm/md and lg/xl. She has a baby head. :laughing:

- I had the same problem. Sm/md too constrictive and lg/xl had no seal.

 

I think the polar wraps might be good if someone's taking a liesurely stroll with no exertion.

Most times it's maybe a wool scarf hiking for us now.

- I really thought we'd be wearing something designed by NASA (or the military) by now...

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Even the polar wrap (from Cabelas), helped breathing very cold air, but left your face soaked after a time. Wet face and freezing air not a good mix.

 

Ah, that's too bad. I guess they still haven't really solved the whole condensation problem.

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Something like this maybe? http://www.skigo.ca/airtrim.php

 

AirTrim Heat/Moisture Exchange Masks available with asthma filter, sport filter and racing filters providing different levels of heat/moisture exchange and air flow.

A "Denali Rating" was offered by a company called GearFlogger doing an "independant review".

They admitted that, "We didn't use it while moving but probably should have."

- Well, ya think?

Another was, "The filters will ice up, which you can clear by blowing through it, and condensation will build up on your skin and inside the mask but that just proves it's doing the job."

- No, not really...

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Another was, "The filters will ice up, which you can clear by blowing through it, and condensation will build up on your skin and inside the mask but that just proves it's doing the job."

- No, not really...

 

It sounds like it's about the same as the others. When I was first trying to come up with a true counter-current design, with check valves to prevent re-breathing, I realized I would have to work a moisture trap into the design, which was feasible, but who wants a bag of lung water hanging around their necks, really. The patent on one of these things suggests that the inhalation sucks the moisture back into the mask, thereby solving the condensation problem, but apparently that is another problem.

 

I keep thinking there has got to be a better solution to this problem, and I can't believe it hasn't been done yet.

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I remember seeing a big bucks ski/snow mask (goggles) that, along with digital readings of temp and direction in the glass (for Terminator wannabes I guess), there were little fans moving the air to prevent fogging.

Tried a similar (and even more expensive) full-face motorcycle helmet from a friend. Digital readings to the side, and small fans. Jogged around the yard (my fat can's not gonna run...) and no sweat.

Maybe something simple (but apparently expensive) like that can solve the problem? Moisture's still there, but doesn't settle kinda thing.

Edited by cerberus1

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I wear a thin balaclava more for protection from the wind. About the only thing I've been able to manage to keep from breathing direct cold air (when it's too cold for me), is to loosely cover the lower face with a scarf when I'm not talking. Moisture is still an issue, but the cloth isn't directly touching me. This will keep a pocket of warmer than the outside air to help breathe back in. It isn't going to be body temp warm but the effect is noticeable.

 

Heat generation is mainly about burning calories. I keep a protein bar handy for the quick bite or two to keep up with the calorie burn and my water tube is tucked into the collar for the quick drink afterwards to help digestion.

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<_< Interesting.

 

For all the years I've been climbing I do not recall using a mask. I generate lots of heat and need to rid of it. I do have a beard and some may consider it a form of mask and it does freeze up at times.

 

I guess I'm just a tad different from most and Totem would say, 'Yep'.

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Hi nonaeroterraqueous;

 

I have read your thread entirely and I find it very amusing and interesting! Honestly, I just signed up on this website to reply to your thread! You seem so serious about the topic and I too share the same sense of attention and urgency to find a suitable replacement.

 

Anyways, I initially was looking for a mask/headwear that would help me run in extreme cold (I am an avid runner/ I run in any condition!) and replace my current ever-so over-soaking balaclava. But to no avail, I couldn't a mask appealing for running (I breath through my nose and exhale by mouth).

There were some masks available like the ones you pointed out but the designs and functionality left me kind of dissatisfied.

 

I might give it a go to create or invent a mask and/or a headwear system to operate in extreme weather conditions. Some of the topics and device I looked into that might help us create a solution:

 

1) Very High Heat Conductors include Carbon Nanotube(single) (3180W/m*K-3500W/m*K) and Graphene(4840W/m*K-5300W/m*K) whereas Copper(385W/m*K - 401W/m*K) - - Might help in heat transfer in the Counter current heat exchange process...

 

2) I looked into the Heat Recovery Ventilation technologies used in homes and it seems likely an ideal concept to use in a mask device - it uses the Counter current heat exchange method. All we need to do is make it smaller. It's probably what they use in all of the mask currently available in the market.

 

3) As for the water vapour issue, maybe we can try to condense them onto bristles/brushes. Then when enough is collected on a bristle, they can safely drip out since they will refreeze as ice/snow dust.(I read an article somewhere online about a research team that found a way to prevent water from freezing below its 0 Celsius by carefully rearranging patterns of bristles on the surface of an object).

 

4) As for design, I looked into silicone or mixed silicone rubber as alternative breathing masks as oppose to fabric. They use silicone rubber or similar material in the manufacturing of gas mask and firefighting gears(only the body core). This can help create a cavity so we can breath through our nose or mouth if required.

 

I'll try and see if I can put all this research together and create a mask. And run anywhere... lol

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I'm eager to find some solution to this problem. Love being outside, but in the cold I'm suffering big time.

Any new developments/findings now we're 4 years later?

 

Edited by Valentijn77

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There's a gizmo company that has a  509 Goggle, and some models have an optional fan with an auto feature (senses "moisture", fans it out).  Bucks enough that I'm sure not doing a product test for snowmobile goggles (though they "say" they'll fit other manufacturers).  :)

Really surprised no one has figured similar yet, though a big difference in sweating, breath, and slight moisture.  A lotta AAA batteries...

Pair that "fan" (that's separate from the mask) with a heat mask somehow...who knows?

Edited by cerberus1

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