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S Mar 28, 2015 at 21:48 history bounty ended CommunityBot
S Mar 28, 2015 at 21:48 history notice removed CommunityBot
Mar 25, 2015 at 0:18 answer added steverino timeline score: 0
Mar 22, 2015 at 7:20 comment added TheEnvironmentalist I'd like to suggest, besides getting a better humidifier, NOT adding an inverter, and here's why: Most devices that run on AC actually use DC, but have an AC to DC converter built in. This converter isn't 100% efficient, neither is an inverter, so assuming the HC500 actually uses DC internally, you'd be plugging in a battery (DC) to convert to AC, for the HC500 to convert back to DC, losing power every step of the way. If you look more closely at the datasheet, there's a good chance with some slight modifications you can remove the AC to DC parts, and then wire a battery almost right in.
Mar 21, 2015 at 13:45 history protected W5VO
Mar 21, 2015 at 9:54 answer added bandybabboon timeline score: 5
Mar 20, 2015 at 23:46 comment added g023 I wonder what the implications would be to have a separate humidifier designed that was more power efficient and meant to run off batteries. Something like an ultrasonic humidifier that needs less wattage. Something like: youtube.com/watch?v=9GBoF8aw7VA
Mar 20, 2015 at 21:44 answer added HopeItHelps timeline score: 0
S Mar 20, 2015 at 19:57 history bounty started dom176
S Mar 20, 2015 at 19:57 history notice added dom176 Improve details
Mar 20, 2015 at 17:39 answer added Guill timeline score: 0
Mar 20, 2015 at 14:51 answer added Kluge timeline score: 0
Mar 19, 2015 at 12:14 comment added MSalters @starbucksguy: Sorry, not a chemical engineer myself so I can't really be more authoritative than Google. And of course you wouldn't need as much steam as a typical industrial application. The reason I suggested it was that a H2O2 solution wouldn't be much heavier than the water you already have to carry around, and the catalyst to decompose it would literally be less than a gram. However, this device would produce some extra oxygen (>300 grams or so in 12 hours, 250 liter) and I'm not medically qualified to state whether that's acceptable. (It would enrich air to about 25% I think)
Mar 19, 2015 at 2:56 comment added starbucksguy @MSalters Could you suggest an online resource where I could learn more about chemical steam generators? Thanks!
Mar 19, 2015 at 2:50 comment added starbucksguy @Gabe I never heard of the Snuggle Hose, but it looks like a great option for insulting the ventilator tubing. Thank you very much for sharing!
Mar 19, 2015 at 2:48 comment added starbucksguy @Korhan the water chamber holds 15.8 fluid ounces (480 ml), and it typically takes ten to twelve hours for the water to completely evaporate. The temperature of the air entering my lungs is kept between 37 and 38 degrees C, though I'm not sure what the actual water temperature is. This humidifier has a heater wire socket and a temperature probe socket that integrate into the ventilator tubing. This, unfortunately, wouldn't be available on a small water heater. I do appreciate your thoughts tho!
Mar 18, 2015 at 16:49 comment added Gabe I would look into an insulated hose cover (snugglehose.com) to reduce or eliminate the power draw from the heated wire.
Mar 18, 2015 at 16:27 answer added Adam Davis timeline score: 7
Mar 18, 2015 at 12:53 comment added user70247 Would you please let me know the volume of the liquid tank and the required amount of time to boil/finish all the liquid in the full tank. Also is it boling the water or just evaporating is enough for you? Depending on your answers I may suggest a 12 Volt around 4 Amp water heater(70-80C) or 12 Volt 8 Amp water boiler. Even can add a thermostate and send for free.
Mar 18, 2015 at 10:15 answer added ratchet freak timeline score: 3
Mar 18, 2015 at 9:41 comment added MSalters From an engineering design viewpoint, a chemical steam generator may make more sense for mobile applications. Hydrogen peroxide decomposition is quite energetic (3 kJ/g).
Mar 18, 2015 at 9:38 comment added user40669 I would seriously suggest obtaining an humidifier designed to run on DC. Using an inverter to convert the battery's DC to AC is highly unefficient and would decrease your battery life even more.
Mar 18, 2015 at 4:33 answer added Filek timeline score: 4
Mar 18, 2015 at 0:38 history edited starbucksguy CC BY-SA 3.0
corrected spelling, added information regarding heated wire
Mar 18, 2015 at 0:03 answer added Karl Bielefeldt timeline score: 36
Mar 17, 2015 at 23:35 comment added Greg d'Eon +1 for a well written and unique question. I love this community.
Mar 17, 2015 at 22:39 comment added Dave Tweed I really don't know. I just wanted to figure out what the basic requirements were based on the physics of the situation. The "heated wire" option, if you are using it, is obviously intended to minimize condensation in the delivery tube. There may be other design subtleties that dictate using extra energy, too. But I'm thinking that if the heating chamber and the delivery tube were suitably insulated, you could get the power requirements down to on the order of 30-40W.
Mar 17, 2015 at 22:20 comment added starbucksguy Thanks everyone for taking the time to look think about this and respond. @DaveTweed what range of power requirements would be optimal for me to for when I'm researching other units? Good efficiency is another great point. Thank you!
Mar 17, 2015 at 21:32 history tweeted twitter.com/#!/StackElectronix/status/577945685040975873
Mar 17, 2015 at 21:06 answer added EM Fields timeline score: 9
Mar 17, 2015 at 21:01 answer added Olin Lathrop timeline score: 26
Mar 17, 2015 at 20:55 answer added user1908704 timeline score: 3
Mar 17, 2015 at 20:42 comment added Dave Tweed Just running the numbers, if you needed 10 l/min. of air at 40 mg/l absolute humidity, and given that the heat of vaporization for water is about 2260 J/g, that means that you'd need about 15 W of heat delivered to the water. The trick to getting good efficiency will be to minimize the heat that is lost to the environment.
Mar 17, 2015 at 20:26 comment added Dave Tweed I looked at the HC500 manual, and it's clear that electrical efficiency was not a high priority in its design. Ease of use, and minimizing the possibility of contamination/infection are obviously much more important. That said, have you searched for alternative units that might have lower power requirements?
Mar 17, 2015 at 20:24 comment added Passerby There are some commercial battery or rechargeable products out there that would probably be cheaper.
Mar 17, 2015 at 20:11 comment added KyranF You would need to attach or pull around on a trolley a car battery or two and an AC inverter (to convert DC battery voltage to the 115V AC) to power the unit.
Mar 17, 2015 at 19:52 review First posts
Mar 17, 2015 at 19:55
Mar 17, 2015 at 19:50 comment added Ignacio Vazquez-Abrams That's not a trivial amount of power. You're going to need tens of kilograms of battery to run it for several hours.
Mar 17, 2015 at 19:48 history asked starbucksguy CC BY-SA 3.0