Clever woodburning stove

[droid_ca]

So is it possible to have some sort of chimney hood or exhaust vent over top of it for indoor use. I have a few ideas running around my head now just trying ti figure them out

[Jiminsav]

I noticed that they already use a black pot on that stove, because any other color is gonna be black soon..and what idiot cooks fried chicken over a fire you can't really control...pu---lease.

[Reddiver]

Just another overpriced Rocket stove ... http://solarcooking.wikia.com/wiki/Rocket_stove
_________________I didnt have a welder available so I built this one out of PVC worked well but didnt last long

[eamarquardt]

even if it just boils water like they said. it would be a aset to me.

but I bet it takes longer than 10 minutes in wyoming at my alutde above sea leval!

I don't think that a wood fire would burn any cooler at 6000 feet than at sea level unless there was a real restriction in the airflow. Water boils at 201f at 6000 feet versus 212f at sea level so I think it's reasonable to conclude that the stove will actually "boil" water faster at altitude but the water won't be as hot as boiling water at sea level.

There you have it again: "The world according to Gus".

Just like a liquid fueled Coleman appliance, I wouldn't use one of these things indoors either. Just a thought.

Cheers,

Gus

[Treeview]

I think a pretty effective and cheap stove could be built using a five gallon bucket and a piece of 4-6" stove pipe. It might not last years and years but so what! Any of these stoves is a big improvement over cooking on an open fire.

[Corwin C]

even if it just boils water like they said. it would be a aset to me.

but I bet it takes longer than 10 minutes in wyoming at my alutde above sea leval!

I don't think that a wood fire would burn any cooler at 6000 feet than at sea level unless there was a real restriction in the airflow. Water boils at 201f at 6000 feet versus 212f at sea level so I think it's reasonable to conclude that the stove will actually "boil" water faster at altitude but the water won't be as hot as boiling water at sea level.

There's a big difference in how wood (or any other fuel) burns at elevation. Just like anything else that consumes oxygen, there just isn't as much available per unit volume up here as at sea level. It cools the fire down quite a bit. I don't know if the actual flame temperature is different, but the time it takes to boil water (even though it boils at a lower temperature) is definitely much longer. Think of it as the opposite of what a blacksmith does in an abundance of fuel with the bellows, more oxygen (air), more heat ... less oxygen (air), less heat.

BTW - Anybody know how to put a set of bellows on Slow's Coleman stove?

[GPW]

Wolf’s right ... without the insulation it can’t achieve the heat to burn the smoke off... Still I wouldn’t use one inside (CO) .... I imagine with no insulation , the dead wood stove would glow cherry red from the heat and be more dangerous than a campfire .. That and a real rocket stove is so CHEAP to make from most anything recycled ...

CC , I’ve made coffee (campfire) at 11, 500 ft. (St.Elmo CA ) and whilst boiling away was only warm enough to drink ...

[pete42]

Thanks Treeview and everyone else who showed this old man things he had never seen before.

all the stoves look like they will work some more efficient than others some harder to build than others but all are way cool.

don't know if I would want to hook my cell phone to the stove while cooking chicken or hamburgers it may look like a Dali piece when done.

pete

[RAYVILLIAN]

These are both rocket stove style stoves. but I really like the biostove with the electric function. Just FYI this is the people that have be developing the idea for third world countries since the 80's or 90's.
http://www.aprovecho.org/web-content/pu ... s/pub1.htm
There is alot of information here if your interested

Gary

[Treeview]

This afternoon I was at the Habitat for Humanity-ReUse store. There was a section of double wall stainless steel chimney. That would be the ticket for this stove!

[eamarquardt]

even if it just boils water like they said. it would be a aset to me.

but I bet it takes longer than 10 minutes in wyoming at my alutde above sea leval!

I don't think that a wood fire would burn any cooler at 6000 feet than at sea level unless there was a real restriction in the airflow. Water boils at 201f at 6000 feet versus 212f at sea level so I think it's reasonable to conclude that the stove will actually "boil" water faster at altitude but the water won't be as hot as boiling water at sea level.

There's a big difference in how wood (or any other fuel) burns at elevation. Just like anything else that consumes oxygen, there just isn't as much available per unit volume up here as at sea level. It cools the fire down quite a bit. I don't know if the actual flame temperature is different, but the time it takes to boil water (even though it boils at a lower temperature) is definitely much longer. Think of it as the opposite of what a blacksmith does in an abundance of fuel with the bellows, more oxygen (air), more heat ... less oxygen (air), less heat.

BTW - Anybody know how to put a set of bellows on Slow's Coleman stove?

I remain "unconvinced". What we need is an experiment with some reasonable controls. I'll check with my local "Mad Rocket Scientist" who has a PhD in heat transfer.

However, if you're using a burner that puts out the same amount of fuel at sea level and at altitude, get complete combustion (ie no soot) with lots of available air, it seems to me that the heat generated by the burning (exothermic chemical reaction) would be roughly the same regardless of altitude (within reason) as the same amount of energy is being created. There are a lot of other considerations as perhaps the transfer of the energy to the pot isn't as good at altitude due to the decreased density of the gasses. I dunno.

If, though, one were to use an electric heater (immersion, electric hotplate, or electric stove) I'd say the heat transfer is unaffected by the altitude and the water would definitely boil faster at altitude as it doesn't have to get as hot.

Enough conjecture in the absence of any real data.

I'd go swimming now but I have to wait a half hour for my lunch to digest so I don't get cramps and drown!

Cheers,

Gus

[Engineer Guy]

We're used to first Camping, then residing, at ~9,000' elevation.

Referencing ~10,000' Leadville CO, there's 10.1 PSI [~525 Torr] there vs. 14.7 PSI [~760 Torr] at Sea Level. There's less of a column of Atmosphere pressing down. This means less Heat - less energy input - is required for Water to change state and overcome the pressurizing effect of a lesser column of Atmosphere. Therefore, Water boils - changes state to a Gas - at lower temperature, as Posted above. Cooking an Egg or Pasta takes longer because the Water temperature is lower.

Meanwhile, there's 30% less Oxygen to feed a Fire at 10,000'. It's the inverse effect of force-feeding Oxygen via Bellows. I can attest that simple things like getting a BBQ started at high elevation takes MUCH longer. I went to using a HD Fan to force-feed Air to a BBQ when entertaining. Otherwise, Cooking took much longer, and folks had to wait too long to eat vs. BBQ'ing at mile-high Denver. Opening a Bag of Chips or a Bottle of Lotion at high elevation is always exciting.

I worked in High Vacuum Engineering for Decades, and we express values in Torr [unless Overseas]. The Links below vary a bit in published values, but they're close enough for 'Gumment Work'.

Altitude Pressure Chart

Altitude -> Oxygen Calculator

[Corwin C]

I wish I still had my notes/texts from my high altitude classes in college. From memory, there is a distinct difference in flame propagation speed in a fuel/air mixture based on the pressure on the system. Essentially, an identical mixture burns slower at low pressure because the molecules are situated farther apart (at least that's how I understood it in my mind.)

This is a huge issue in keeping aircraft turbine engines operating at altitude, especially in a re-start situation because the combustion chamber pressure quickly drops to ambient (or at least ram) pressure. Being able to start an engine at altitude is a huge certification/safety issue. I remember a lab where we were igniting a sample hydrogen/oxygen (ideal mix) at lower and lower pressures. Eventually, at VERY low pressure (if I remember correctly, around 0.01psi [1 Torr]), even hydrogen/oxygen would not burn.

The big difference here from what I was taught, is that in a wood/air situation there is an abundance of fuel and the air(oxygen) supply is the limiting factor (hence the bellows helping the situation.)

Another thought/possibility, at lower pressures, establishing an efficient heat convection situation where the combustion gasses draw fresh air to the flame may be compromised. I would really like to hear what your "rocket scientist" friend can add to clear up the question.

As far as collecting experimental data ... shouldn't be too difficult. Identical heat source/volume of water/initial water temperature, and measure time to boil/boil temperature at several different elevations. Maybe after the "holiday time crunch" I can get something set up.

[pete42]

It's going to be a long winter.................

[hugh]

Heres another version, this one heats water as well as cooking
http://www.kellykettleusa.com/