I was thinking the same. Hey Robert, for the next iteration, you don't need more steel, just block those holes by welding a bit of plate over them and then bore new holes down lower. You could even do your IR before and after and you'll have 3 measurements, 1. High holes, 2 no holes, 3 low holes 🙂
The swirl in the fire box appears to simply be the result of the Coriolis force, but it might also be a result of air deflection from your preheater coming in at a 45 degree angle too.
If one was to install offset semicircular sections pf pipe, shaped something like a progressive French curve to direct the air flow from the air ports at the base of the chimney, one will get a very definite vortex.
@@tobygathergood4990 Any unified deflection will certainly help. For instance, even so little as angling the drill holes will give a slight twist. Also, just adding circular pipe into the chimney its self will help, as the turbulent recesses of a square tube by nature resist a smooth vortex, even while they make tiny eddy countercurrents. If you took a piece of anything round [say, stove pipe or steel pipe] and put that on the discharge, then directed the exhaust from the main char-burn chamber through a tapered deflector to one side, and then filled the rest with that 'pre-heated' air on the other side, it would swirl quite vigorously indeed. This would also allow one to insert the fresh air into the center of the combustion, instead of the outside. The ideal arrangement would be to have the stream of hot gases entirely enveloped, as a very thin stream, into a rapidly spinning vortex to maximize the fuel-to-air surface contact, and I can draw up a simple sketch of that, should people be curious as to how I suggest it would best work. All of this can still be done pretty cheaply, with simple tools like he is already using, and simple pieces of plate and pipe.
I just saved that as a chapter for a book on thermodynamics and fluidics in combustion theory I need to complete... If people would like that as a .PDF, .ODT, or .DOC file let me know where to send it.
You are so close! Try 12 hole! Or take a ashtray divide into two! and put it on a bit bigger cylinder shaped jar on left side let the heat get out in a vortex (prepare with more oxygen) to the tin-jar! That can be done pretty easy, hope you se my word positively for I just love your work Rob! 🥸
Thanks for another great video! The J-tube portion of a "rocket" stove/heater is meant to be insulated (fire brick, ceramic blanket, castable refractory cement, etc), this promotes gassification by keeping the temperature quite high, especially in conjunction with a warm-air intake (the outlet of which could be positioned in immediate proximity to the final bend), and a thermal mass for heat exchange on down the line. The thermal mass can give an opportunity for any unburned components to add heat after sufficient build up of creasotes and the like. Chimney fires are desirable in such a "Rocket Mass Heater", as they simply add more heat to the system.
Very good Rob! Your design has advantages over a pulse jet. Air intake directly into an expanded burn chamber and you would have a pulse jet rather than a rocket stove if your air was super heated first. Your design has an advantage for a stove though as your fuel will last longer. Bravo! I like it! Keep it up Rob! Thanks for the video.
You, Sir, remind me of my 7th grade math teacher in that he made math intriguing and caused his students to want to know "why"!!! I applaud you in this!
Great idea 💡 to add holes at that location! For ease of use, maintenance, cleaning, it would be nice if that vent your adding allowed you to remove the riser. The riser could fit on top of the air vent for easy assembly without covering the air vent holes. That's what I would do. Also, the best designed ones imo have a means of bring in fresh air from outside and venting air outside using cheap standard gas pipe vents. Forget what they are called. I've even seen someone use gutters. Lol. If it works.
Right on. Been pondering a rocket gasified vortex burner for a while. Looks like 3-4 semi circular intake fins after main combustion could be cool. They could draw air from a dual walled combustion/ intake area.
A lot of rocket stoves seen on TH-cam seem to take extra steps to keep the final burn chimney hot. These are pre-heating of the secondary air feed to avoid cooling of the final burn chimney and a cover, often put over the chimney, again to keep the chimney itself hot. I have never built a rocket stove so I don't claim to know if this really makes any difference to the complete combustion we would all want for reduced emissions and full fuel use.
I have used this as a modification on a wood stove and installed a scavenger box cutter up the chimney. It works great I use less wood to get the same amount of heat
Rob... Hoping you will consider adding a bell (like the flower pot) to slow the exhaust games to allow more heat to transfer to the living space before heading out the chimney.
nice idea mate - i probably won't as this is an experimental model meant for hacking about with - but i like the idea yu should try it and tell everyone how it works out
This is basically how my wood furnace in my house is built. There is a main (sealed) door 6 inches above the floor of the chamber in which to fuel is loaded, typically split fir, pine and birch wood logs. The burn chamber, lined with fire brick, is 30 inches deep front to back, 15 inches wide, 24 inches tall. On each side is a top to bottom steel plate that draws air in from an air door below the main fuel door. There are are vertical oval internal air ports at the bottom in the plates at the entrance near the fuel door, in the center but the back is open top to bottom of the plates which extend to about half way up the sides of the burn chamber. At the top of the burn chamber are two overlapping plates spaced about 2 inches apart, that slow down the escape of burnt gasses and any flame into an insulated 6 inch steel pipe which is situated at the far back of the chamber. There is a forced air fan that acts as a bellows to begin the burn and shuts off automatically at a specific temperature setting. The air door can also be controlled electrically via an adjustable reading thermocouple. The gasses exhaust through the 48 inch long by 6 inch steel pipe that is set at an upwards angle of about 30 degrees into a concrete chimney flue lined with rectangular ceramic firebrick pipe sections. On the next floor above where the chimney breast goes through the room floor to ceiling, is a hole into the chimney about half way up, to which can either be attached a secondary wood stove steel pipe flue, or in this case, a heavy steel plate fitted with large radiating fins with extensions into the chimney proper in order to catch the heat from the spent combustion gases. The furnace is also attached to a system of hot air pipes fed by a temperature controlled furnace blower to effect central heating. The entire installation is approximately 40 to 45 years old. The only innovations I have implemented is the heavy steel plate to catch the exhaust gas heat on the upper floor and the overlapping heat plates in the burn chamber.
Two suggestions, first drill the holes in each opposing side but in a group close to the opposite edges so the incoming air induces a vortex, secondly other users have found a ratio of 5:1 for primary air to secondary as the best mix. Perhaps add a flap valve to fine tune this. Ah, a third suggestion… and please use preheated secondary air with a cowling arrangement.
On a rocket stove a friend and I built, we drilled holes 3/4 up the flu. It was a J-tube and we had it inside 2 metal boxes, one horizontal (where wood burned) and the other vertical (with J-tube flu inside it), separated by a divider with a hole only big enough for the J-tube to pass through. Drilled holes 3/4 up the J-tube and at bottom of the vertical box. Air entered (was sucked into) holes at bottom of vertical box, went up, and entered the flu through holes in the J-tube 3/4 of the way up. At first, we didn't drill enough holes in outer box and the walls of the outer box went concave when it came up to heat. Drilled more holes until it stopped sucking in the walls and it worked great, no smoke. We even tossed an oil-soaked rag in the fire and it made no smoke. (We were experimenting, so don't throw hate for pollution. We still think the stack effect contributed to that initial suction. That initial suction was so forceful that I've been toying with the idea of putting a 2nd flu in the vertical box to just pull air and putting a small wind turbine at the intake of the second flu just to see how much electricity it will generate just from the hot air rising. Thought about TEGs or Peltier devices, and it can be done, but they're expensive. If a second flu or pipe can go into vertical box beside the flu that carries smoke, a mini wind turbine might be a cheaper, more effective method.
BTW, outer boxes were made with sheet metal, which was thin enough to be somewhat flexible. That's why the vertical box went concave when there were not enough air intake hokes at the bottom.
I thought you were going to update the newer rocket stove with a hot air intake, but the results with the old one and what would seem like purpose-defeating holes was amazing!
So if you now make an outer liner for the chimney and fill it with sand, you have a heat battery which will keep giving out heat after the fire has burnt out.
Awesome videos thanks ! could you engineer this to auto feed and burn used oil cleanly/safely for emergency situations on your final build. Cant wait to see it .
Did you see his video about catalytic heaters? Might be suitable, especially behind glass. Or maybe an outdoor quasi-boiler with an automotive heater core... Maybe using a ghillie kettle to heat the fluid efficiently.
Since you are adding enclosed air intakes to allow for preheating, would it also makes sense to capture that heat along the chimney with a thermal mass
use heatpipes like from cpu colers to transfer more heat to where it is needed (gassification chamber). Preferably make your own copper heatpipes, should not be too difficult.
Very interesting mods Robert and its suprised me how much apparent heat that small collection of wood made .Just a thought on seeing it ,maybe a thermoelectric generator on the side of the fire driving a low voltage fan forcing air into your side inlet?
it's a good idea mate - my own tendancy is towards passive options as they don't break down - but active forced air through the use of a fan is a good idea for sure
I’m in a rental with a 1990’s wood stove fireplace, I’m thinking to retrofit some gas line pipes in it to get oxygen up to the top of the chamber for the re-burn... seems to be the way.
@@ThinkingandTinkering We had an open fireplace when I was a kid and we burned coal in it plus the occasional pinecone. Great memories. Yes, who doesn't like a nice fire.
would putting a jacket around the chimney with a -say- 20mm clearance and stopping 200mm from the top of the chimney not solve the air pre-heating issue, as the chimney would be heating the air on the way down to the holes. Maybe 10mm. Experiment! Thanks for the vids - always inspiring
I went through the rocket stove phase which is why I now heat my home with one a pellet burner homemade gravity fed I don’t really know if adding holes to it does Mine doesn’t have any holes but it does go into a larger barrel and then get vented out lower but it’s smoke-free
@B K - well done with the pellet burner! I've built a bunch of rough test setups that seem to show that 'enough air' in the main intake can do the trick. Excess air, if you like. By enlarging the intake (crudely brick built, mostly) we can get even a 'short' heat riser to do a clean smoke-free burn as demonstrated. The 'extra air' passes through the confused burn region (twigs and bits) along with the fresh wood gas and encounters fierce vortex mixing at the base of the heat riser. Once up to working temperatures this mixing ensures that no wood gas leaves unburned, verified by flue test analysers. Controlling the air/wood gas ratio with twigs and bricks is tricky! A bit of excess air is OK, too much cools the burn.
Instead of holes use 2 pipes in the top corners from the inlet too the chimney. Fun one to the back and stop the other just as it enters chimney. Cut 45 degree angles on them so the air coming out goes around the chimney😁😁
I wonder if the holes were moved to the corners, 2 or 3 holes vertically on say only the right of each side. That would be say 3 holes on the right of each of 4 sides. Or even just short vertical slots with a grinder also only on the right of each face. It would rotate the flame nicely. Almost as well as the fire extinguisher.
So, instead of the holes , it might be cool to cut and bend "vortex flaps" for your air intake. (though installing some on the inside behind your drilled holes would probably be easier, thinking on it). Don't know if there would be a point to it other than the cool factor of a flaming vortex in a box.
It would perhaps make the footprint more compact to build it as an inverlute. fire box/preheater intake on the straight part, run into a round chimnea. I mean, that doesn't Matter at all but it seems like a neat design if one had a sturdy metal inverlute around.
I'm wondering if you drilled the holes near the bottom, but just along one edge and on the opposite side along the other edge (diagonally). Not sure if that makes sense, but you would create a better vortex. Thoughts???
We just got our order of carbon felt..we’re going to do some experiments for backup heat. We’re planning a mobile shipping container home build and will be utilizing some of your various cool heating options as backup heat 2 and 3 in addition to our micro wood stove main heat source.
Since that's made of square stock, it's not a far leap to make it mountable on a standard hitch receiver so you can just bolt it up on the back of your truck.
to heat the room more efficiently wouldn't it b better to have a ducted cone suspended above the chimney (the pointy end inside the chimney) so the gas spreads more evenly around the room?
Great explanation of principle on the rocket stove. What would be great is actual values necessary for ultra efficiency and combustion. Would you be able to tell exactly what the ture values are Robert ???? Thanks fella.
Do you have footage how the original rocket stove worked before you added the 11x2 holes into it? I thought Rocket Stoves originally had no soot because of the 1:1 intake to output air. So I wouldn't have even thought to add the 11x holes
I've been working with stainless wire pan scourers with candles, so far the results seem to be improving the burn, but if you reduce the exhaust flow out then the fire suffers badly
Are you able to use these like inside a building if you were to lose power which affected your heating especially if it were too effective for a day or two or would you need to still make sure that this was vented to the outside if you're burning as efficiently is what is implied then you should be able to burn inside wouldn't you?
What are the final resulting products of this much cleaner burn? Would this be suitable for indoor use without the typical venting of a classic stove pipe
Thanks for the videos. These designs would be improved with a waste ash disposal feature so it doesn't get blown out the chimney or interfere with combustion.
Not sure why you want to heat the separate air intake, although where it enters will cause the vortex, hot air is less dense than cold air and contains less oxygen for the same volume.
I wonder if you could have gotten that vortex rotation and it being the direction you wanted if the holes had been drilled with smaller bit that you take and then go through with it at an angle all the same direction around it, so the air would bank off one side as well as tilt that angle upward too. (like these slashes if they were the direction of the holes \\\\\ so to speak)
Could you incline it such that only the aches are going out the front without burning material going out or something like that to making it a continuous burner?
How would it go to create a couple of vertical slots at the bottom of the chimney and bend one wall inwards (or outwards) to replicate the vortex you showed recently with the 3 sections of fire extinguisher and the little candle?
I thought you got all the air you need from the air getting sucked into the horizontal opening? Would the extra holes decrease the pressure from that process? I suppose a positive would be that the extra holes would create more turbulence and mixing?
Having looked around at one or two other rocket stove contributors, plus having a mental conversation with Mr Spock, surely, on the blacksmith forge principle, if you were to blow air through, from the input hole, you would get loads of oxygen and heat - so you're aiming to get a similar effect by instead generating draw up the chimney. Many others insulate the chimney - do you think this would increase the temperature enough to significantly affect the amount of draw? I find it hard to believe that the velocity of the air in the chimney is already so great that you need more holes in the base to let in more air - isn't that cart before horse? Generate more draw, then, if need be, admit more air? Possibly the relationship between the cross-section of the horizontal and vertical tubes? Loving the videos!
You should totally put on a hand crank hopper feeder or tie it into your human powered hamster wheel . This would give Luke something to do. He could be your canis vertigus this winter. You might be able to heat your whole block. LOL JK. Great teaching. Thank you sir.
I would think that if you drilled the holes on only one side (the right side) of each face of the chimney, you would create a counter clockwise rotation of air in the chimney taking advantage of the Coriolis effect
i love this! i've seen rocket stoves that have a really long horizontal exhaust through a mass (collects heat), some so long that they had to create a valve to direct the hot gases direct to the chinmey first (while starting up) to heat it up enough to create the draw required to pull the cold air through the horizontal mass when you flick the valve over. I'm now wondering how much the holes would reduce the ability to push air through the system without back flowing/spilling out the holes (if you were wanting to push a large amount of air with it). maybe one of those tesla one way valves (no moving parts) would be able to resist the back flow problem? it could act as the heat jacket too, may be horrible to clean though...
Hey I have no techno ability- but I had a dream that an Indian boy was in my home… giving me a introduction to his invention to create eternal energy. I can still see this invention in my minds eye. I would love to run it by you. Sounds crazy… wtf? I’m so weirded out but really want to know why I have details of an invention in my mind? 😮
Instead of drilling holes for more O2, cut a flap on each side and crest a vortex effect for better combustion. Also, I wonder how well coal would work with such a set up?
I've been thinking of making a rocket stove like this out of a old gas tank and oxygen tank, however im thinking of adding an extra linear tank sleeve and between the gap run a coil of pipe packed in sand in which to heat water, sort of in a jacket around the upright. What do you think? 🤔
excellent Mr chuckle !
Thank you kindly lol
Love it and your presentation and enthusiasm. Your humour is also appreciated. thks
Tracking the flue temp with IR, before and after, would have been good to see. Thanks
I was thinking the same. Hey Robert, for the next iteration, you don't need more steel, just block those holes by welding a bit of plate over them and then bore new holes down lower. You could even do your IR before and after and you'll have 3 measurements, 1. High holes, 2 no holes, 3 low holes 🙂
Same
round vortex in a square tube, GJ!
cheers mate
Really enjoy these videos. Thanks for taking us on this journey with you.
cheers mate
The swirl in the fire box appears to simply be the result of the Coriolis force, but it might also be a result of air deflection from your preheater coming in at a 45 degree angle too.
If one was to install offset semicircular sections pf pipe, shaped something like a progressive French curve to direct the air flow from the air ports at the base of the chimney, one will get a very definite vortex.
@@tobygathergood4990 Any unified deflection will certainly help. For instance, even so little as angling the drill holes will give a slight twist.
Also, just adding circular pipe into the chimney its self will help, as the turbulent recesses of a square tube by nature resist a smooth vortex, even while they make tiny eddy countercurrents.
If you took a piece of anything round [say, stove pipe or steel pipe] and put that on the discharge, then directed the exhaust from the main char-burn chamber through a tapered deflector to one side, and then filled the rest with that 'pre-heated' air on the other side, it would swirl quite vigorously indeed.
This would also allow one to insert the fresh air into the center of the combustion, instead of the outside.
The ideal arrangement would be to have the stream of hot gases entirely enveloped, as a very thin stream, into a rapidly spinning vortex to maximize the fuel-to-air surface contact, and I can draw up a simple sketch of that, should people be curious as to how I suggest it would best work.
All of this can still be done pretty cheaply, with simple tools like he is already using, and simple pieces of plate and pipe.
Coriolis.......lol. I suppose my toilet does the same.
@@hunnybunnysheavymetalmusic6542 Agreed.
I just saved that as a chapter for a book on thermodynamics and fluidics in combustion theory I need to complete...
If people would like that as a .PDF, .ODT, or .DOC file let me know where to send it.
Thats great. Looking forward to the final evolution of rocket stove gasification with vortex clean burn
You are so close! Try 12 hole! Or take a ashtray divide into two! and put it on a bit bigger cylinder shaped jar on left side let the heat get out in a vortex (prepare with more oxygen) to the tin-jar! That can be done pretty easy, hope you se my word positively for I just love your work Rob! 🥸
Just like Blue Peter - here's one I prepared earlier. Fantastic. I'm looking forward to watching the final increment.
Thanks for another great video!
The J-tube portion of a "rocket" stove/heater is meant to be insulated (fire brick, ceramic blanket, castable refractory cement, etc), this promotes gassification by keeping the temperature quite high, especially in conjunction with a warm-air intake (the outlet of which could be positioned in immediate proximity to the final bend), and a thermal mass for heat exchange on down the line. The thermal mass can give an opportunity for any unburned components to add heat after sufficient build up of creasotes and the like. Chimney fires are desirable in such a "Rocket Mass Heater", as they simply add more heat to the system.
cheers mate - i didn't do that as this is really an experiemntal version but nice tip
Very good Rob! Your design has advantages over a pulse jet. Air intake directly into an expanded burn chamber and you would have a pulse jet rather than a rocket stove if your air was super heated first. Your design has an advantage for a stove though as your fuel will last longer. Bravo! I like it! Keep it up Rob! Thanks for the video.
You, Sir, remind me of my 7th grade math teacher in that he made math intriguing and caused his students to want to know "why"!!! I applaud you in this!
wow - cheers mate - that is indeed a great compliment
I love your dedication.
Great idea 💡 to add holes at that location! For ease of use, maintenance, cleaning, it would be nice if that vent your adding allowed you to remove the riser. The riser could fit on top of the air vent for easy assembly without covering the air vent holes. That's what I would do.
Also, the best designed ones imo have a means of bring in fresh air from outside and venting air outside using cheap standard gas pipe vents. Forget what they are called. I've even seen someone use gutters. Lol. If it works.
Excellent!! Cheers from London 👍🏴🇬🇧
Great development! Thanks for showing this.
Great progress! I hope you give your 3 curved plates, set apart by 120 degrees, as your air intake rather than holes. (or maybe in addition to holes)
Right on. Been pondering a rocket gasified vortex burner for a while. Looks like 3-4 semi circular intake fins after main combustion could be cool.
They could draw air from a dual walled combustion/ intake area.
A lot of rocket stoves seen on TH-cam seem to take extra steps to keep the final burn chimney hot. These are pre-heating of the secondary air feed to avoid cooling of the final burn chimney and a cover, often put over the chimney, again to keep the chimney itself hot. I have never built a rocket stove so I don't claim to know if this really makes any difference to the complete combustion we would all want for reduced emissions and full fuel use.
I love this channel. Thanks for the video.
You are jaw dropping awesome. Thank you.
wow - cheers mate and thank you for taking the time to say that
Awesome! Have enjoyed the step by step improvements. Thank you!
I have used this as a modification on a wood stove and installed a scavenger box cutter up the chimney. It works great I use less wood to get the same amount of heat
Great job 👍🤓
"When I was slavishly following everybody else's ideas..." 😂👏
very cool, you're an inspiration thanks. if there was just a line of holes at the right side of each side, then maybe that would create a vortex..
Great Rob. I have made one as I follow on! Australia
awesome mate
Rob...
Hoping you will consider adding a bell (like the flower pot) to slow the exhaust games to allow more heat to transfer to the living space before heading out the chimney.
nice idea mate - i probably won't as this is an experimental model meant for hacking about with - but i like the idea yu should try it and tell everyone how it works out
This is basically how my wood furnace in my house is built. There is a main (sealed) door 6 inches above the floor of the chamber in which to fuel is loaded, typically split fir, pine and birch wood logs. The burn chamber, lined with fire brick, is 30 inches deep front to back, 15 inches wide, 24 inches tall. On each side is a top to bottom steel plate that draws air in from an air door below the main fuel door. There are are vertical oval internal air ports at the bottom in the plates at the entrance near the fuel door, in the center but the back is open top to bottom of the plates which extend to about half way up the sides of the burn chamber. At the top of the burn chamber are two overlapping plates spaced about 2 inches apart, that slow down the escape of burnt gasses and any flame into an insulated 6 inch steel pipe which is situated at the far back of the chamber. There is a forced air fan that acts as a bellows to begin the burn and shuts off automatically at a specific temperature setting. The air door can also be controlled electrically via an adjustable reading thermocouple. The gasses exhaust through the 48 inch long by 6 inch steel pipe that is set at an upwards angle of about 30 degrees into a concrete chimney flue lined with rectangular ceramic firebrick pipe sections. On the next floor above where the chimney breast goes through the room floor to ceiling, is a hole into the chimney about half way up, to which can either be attached a secondary wood stove steel pipe flue, or in this case, a heavy steel plate fitted with large radiating fins with extensions into the chimney proper in order to catch the heat from the spent combustion gases. The furnace is also attached to a system of hot air pipes fed by a temperature controlled furnace blower to effect central heating. The entire installation is approximately 40 to 45 years old. The only innovations I have implemented is the heavy steel plate to catch the exhaust gas heat on the upper floor and the overlapping heat plates in the burn chamber.
Can you please give us a detailed photo/draw of this?
God bless you
brilliant, 11 holes are awesome
You should look up the liberator rocket stove. It's the only rocket stove in the USA allowed for home use. Really interesting design.
Two suggestions, first drill the holes in each opposing side but in a group close to the opposite edges so the incoming air induces a vortex, secondly other users have found a ratio of 5:1 for primary air to secondary as the best mix. Perhaps add a flap valve to fine tune this. Ah, a third suggestion… and please use preheated secondary air with a cowling arrangement.
Very interesting Robert, thanks for perfecting science!
Insulation around the rocket stove improves combustion.
Good job 👍
I wish I had a chimney on my house. Definitely making one for the workshop though
On a rocket stove a friend and I built, we drilled holes 3/4 up the flu. It was a J-tube and we had it inside 2 metal boxes, one horizontal (where wood burned) and the other vertical (with J-tube flu inside it), separated by a divider with a hole only big enough for the J-tube to pass through. Drilled holes 3/4 up the J-tube and at bottom of the vertical box. Air entered (was sucked into) holes at bottom of vertical box, went up, and entered the flu through holes in the J-tube 3/4 of the way up.
At first, we didn't drill enough holes in outer box and the walls of the outer box went concave when it came up to heat. Drilled more holes until it stopped sucking in the walls and it worked great, no smoke. We even tossed an oil-soaked rag in the fire and it made no smoke. (We were experimenting, so don't throw hate for pollution.
We still think the stack effect contributed to that initial suction.
That initial suction was so forceful that I've been toying with the idea of putting a 2nd flu in the vertical box to just pull air and putting a small wind turbine at the intake of the second flu just to see how much electricity it will generate just from the hot air rising.
Thought about TEGs or Peltier devices, and it can be done, but they're expensive. If a second flu or pipe can go into vertical box beside the flu that carries smoke, a mini wind turbine might be a cheaper, more effective method.
BTW, outer boxes were made with sheet metal, which was thin enough to be somewhat flexible. That's why the vertical box went concave when there were not enough air intake hokes at the bottom.
Can't wait for the "I'll just put the kettle on" video 😂
I thought you were going to update the newer rocket stove with a hot air intake, but the results with the old one and what would seem like purpose-defeating holes was amazing!
cheers mate
Great video as always!
Any idea how to best incorporate a copper coil for water heating?
So if you now make an outer liner for the chimney and fill it with sand, you have a heat battery which will keep giving out heat after the fire has burnt out.
Awesome videos thanks ! could you engineer this to auto feed and burn used oil cleanly/safely for emergency situations on your final build. Cant wait to see it .
Very interesting Rob. Is there such a thing as a heater for a wood workshop, namely no flame? Thanks Geoff
Did you see his video about catalytic heaters? Might be suitable, especially behind glass.
Or maybe an outdoor quasi-boiler with an automotive heater core... Maybe using a ghillie kettle to heat the fluid efficiently.
The next set of holds may be treaded for tuning intake with bolts???
Since you are adding enclosed air intakes to allow for preheating, would it also makes sense to capture that heat along the chimney with a thermal mass
use heatpipes like from cpu colers to transfer more heat to where it is needed (gassification chamber). Preferably make your own copper heatpipes, should not be too difficult.
Maybe pipes running through the drilled holes, curving upwards, so oxygen is reintroduced a couple of inches above the flames
Very interesting mods Robert and its suprised me how much apparent heat that small collection of wood made .Just a thought on seeing it ,maybe a thermoelectric generator on the side of the fire driving a low voltage fan forcing air into your side inlet?
Wouldn't the vortex created inside make a partial vacuum and suck air in anyway?
it's a good idea mate - my own tendancy is towards passive options as they don't break down - but active forced air through the use of a fan is a good idea for sure
I’m in a rental with a 1990’s wood stove fireplace, I’m thinking to retrofit some gas line pipes in it to get oxygen up to the top of the chamber for the re-burn... seems to be the way.
I love your penchant for setting things on fire. Winter is coming...
who doesn't like a nice fire lol
@@ThinkingandTinkering We had an open fireplace when I was a kid and we burned coal in it plus the occasional pinecone. Great memories. Yes, who doesn't like a nice fire.
Waiting with bated breath mate , brilliant can’t wait !!
So,.......Everytime I start building something that I think is cool, you improve it and I have to start again. Arrrgghhh!
would putting a jacket around the chimney with a -say- 20mm clearance and stopping 200mm from the top of the chimney not solve the air pre-heating issue, as the chimney would be heating the air on the way down to the holes. Maybe 10mm. Experiment!
Thanks for the vids - always inspiring
I went through the rocket stove phase which is why I now heat my home with one a pellet burner homemade gravity fed I don’t really know if adding holes to it does Mine doesn’t have any holes but it does go into a larger barrel and then get vented out lower but it’s smoke-free
@B K - well done with the pellet burner! I've built a bunch of rough test setups that seem to show that 'enough air' in the main intake can do the trick. Excess air, if you like. By enlarging the intake (crudely brick built, mostly) we can get even a 'short' heat riser to do a clean smoke-free burn as demonstrated. The 'extra air' passes through the confused burn region (twigs and bits) along with the fresh wood gas and encounters fierce vortex mixing at the base of the heat riser.
Once up to working temperatures this mixing ensures that no wood gas leaves unburned, verified by flue test analysers. Controlling the air/wood gas ratio with twigs and bricks is tricky! A bit of excess air is OK, too much cools the burn.
Instead of holes use 2 pipes in the top corners from the inlet too the chimney. Fun one to the back and stop the other just as it enters chimney. Cut 45 degree angles on them so the air coming out goes around the chimney😁😁
I wonder if the holes were moved to the corners, 2 or 3 holes vertically on say only the right of each side. That would be say 3 holes on the right of each of 4 sides. Or even just short vertical slots with a grinder also only on the right of each face. It would rotate the flame nicely. Almost as well as the fire extinguisher.
i will have to try it mate
So, instead of the holes , it might be cool to cut and bend "vortex flaps" for your air intake. (though installing some on the inside behind your drilled holes would probably be easier, thinking on it). Don't know if there would be a point to it other than the cool factor of a flaming vortex in a box.
It would perhaps make the footprint more compact to build it as an inverlute. fire box/preheater intake on the straight part, run into a round chimnea. I mean, that doesn't Matter at all but it seems like a neat design if one had a sturdy metal inverlute around.
I'm wondering if you drilled the holes near the bottom, but just along one edge and on the opposite side along the other edge (diagonally). Not sure if that makes sense, but you would create a better vortex. Thoughts???
We just got our order of carbon felt..we’re going to do some experiments for backup heat. We’re planning a mobile shipping container home build and will be utilizing some of your various cool heating options as backup heat 2 and 3 in addition to our micro wood stove main heat source.
Looks good now we need to concentrate on 100% heat extraction so we could use a plastic pipe for a chimney.
Since that's made of square stock, it's not a far leap to make it mountable on a standard hitch receiver so you can just bolt it up on the back of your truck.
for sure
You might want to weild small plates over the existing holes to see if your new hole placement is truely better.
good point - cheers mate
I would use round pipe for the vertical part.
to heat the room more efficiently wouldn't it b better to have a ducted cone suspended above the chimney (the pointy end inside the chimney) so the gas spreads more evenly around the room?
Great explanation of principle on the rocket stove. What would be great is actual values necessary for ultra efficiency and combustion. Would you be able to tell exactly what the ture values are Robert ???? Thanks fella.
Do you have footage how the original rocket stove worked before you added the 11x2 holes into it? I thought Rocket Stoves originally had no soot because of the 1:1 intake to output air. So I wouldn't have even thought to add the 11x holes
Cool! Could stainless steel wool be used at the top to make more radiant heat?
I've been working with stainless wire pan scourers with candles, so far the results seem to be improving the burn, but if you reduce the exhaust flow out then the fire suffers badly
Are you able to use these like inside a building if you were to lose power which affected your heating especially if it were too effective for a day or two or would you need to still make sure that this was vented to the outside if you're burning as efficiently is what is implied then you should be able to burn inside wouldn't you?
Maybe try making an adjustable air intake for the secondary intake so you can tweak the secondary burn.
What are the final resulting products of this much cleaner burn? Would this be suitable for indoor use without the typical venting of a classic stove pipe
Thanks for the videos. These designs would be improved with a waste ash disposal feature so it doesn't get blown out the chimney or interfere with combustion.
“Why eleven? Because I think it looks pretty!” As someone else once said “Boom! Science!”
Not sure why you want to heat the separate air intake, although where it enters will cause the vortex, hot air is less dense than cold air and contains less oxygen for the same volume.
I wonder if you could have gotten that vortex rotation and it being the direction you wanted if the holes had been drilled with smaller bit that you take and then go through with it at an angle all the same direction around it, so the air would bank off one side as well as tilt that angle upward too. (like these slashes if they were the direction of the holes \\\\\ so to speak)
Could you incline it such that only the aches are going out the front without burning material going out or something like that to making it a continuous burner?
i would think so
How would it go to create a couple of vertical slots at the bottom of the chimney and bend one wall inwards (or outwards) to replicate the vortex you showed recently with the 3 sections of fire extinguisher and the little candle?
i think ti would mate and i have ordered the steel to do exactly that lol - nice suggestion - cheers
No deliberate attempt to a vortex chimney in the next iteration?
Hot stuff!
I thought you got all the air you need from the air getting sucked into the horizontal opening? Would the extra holes decrease the pressure from that process? I suppose a positive would be that the extra holes would create more turbulence and mixing?
Having looked around at one or two other rocket stove contributors, plus having a mental conversation with Mr Spock, surely, on the blacksmith forge principle, if you were to blow air through, from the input hole, you would get loads of oxygen and heat - so you're aiming to get a similar effect by instead generating draw up the chimney. Many others insulate the chimney - do you think this would increase the temperature enough to significantly affect the amount of draw? I find it hard to believe that the velocity of the air in the chimney is already so great that you need more holes in the base to let in more air - isn't that cart before horse? Generate more draw, then, if need be, admit more air? Possibly the relationship between the cross-section of the horizontal and vertical tubes? Loving the videos!
Could vertical air slits create a Vortex effect ?
What is the minimum Flue Angle to maximize heat in home? 45 degree angle?
You should totally put on a hand crank hopper feeder or tie it into your human powered hamster wheel . This would give Luke something to do. He could be your canis vertigus this winter. You might be able to heat your whole block. LOL JK. Great teaching. Thank you sir.
what good is the rocket stove?
how is it useful? Is it a space heater?
I would think that if you drilled the holes on only one side (the right side) of each face of the chimney, you would create a counter clockwise rotation of air in the chimney taking advantage of the Coriolis effect
interesting idea - want to give it a go?
Could you weld patch plates over the holes and drill the new holes instead of refabricating?
Nice .make 2 slots with an angle grinder toll. for more vortex
I’d be interested in seeing a non powered feed for wood pellets that could be shut off.
You could drill those holes with an angle grinder drill adaptor
that exists? wow - i never even knew there was such a thing - cheers mate
Daft question perhaps, but if this was sat on your open-fire hearth with the chimney up the chimney, would the heat be coming back into the room?
Do pre and post hole heat tests
Nice work, although my insurance would have a fit if they saw this in my cabin lol!
i love this! i've seen rocket stoves that have a really long horizontal exhaust through a mass (collects heat), some so long that they had to create a valve to direct the hot gases direct to the chinmey first (while starting up) to heat it up enough to create the draw required to pull the cold air through the horizontal mass when you flick the valve over.
I'm now wondering how much the holes would reduce the ability to push air through the system without back flowing/spilling out the holes (if you were wanting to push a large amount of air with it).
maybe one of those tesla one way valves (no moving parts) would be able to resist the back flow problem? it could act as the heat jacket too, may be horrible to clean though...
Hey I have no techno ability- but I had a dream that an Indian boy was in my home… giving me a introduction to his invention to create eternal energy.
I can still see this invention in my minds eye.
I would love to run it by you.
Sounds crazy… wtf?
I’m so weirded out but really want to know why I have details of an invention in my mind? 😮
Instead of putting holes at the elbow, I prefer the insulation idea from one of your earlier videos. The holes you have are good!
But if you insulate it, all the heat goes up the chimney. Is this a "room heater" or a "cook stove"?
Now to build this into a rocket MASS heater....little fire, no smoke, mass heats up - fire goes out, but the heat radiates for a long time....
Instead of drilling holes for more O2, cut a flap on each side and crest a vortex effect for better combustion.
Also, I wonder how well coal would work with such a set up?
Instead of just popping some holes in the bottom, how about a sliding vent so you can adjust the air input?
I've been thinking of making a rocket stove like this out of a old gas tank and oxygen tank, however im thinking of adding an extra linear tank sleeve and between the gap run a coil of pipe packed in sand in which to heat water, sort of in a jacket around the upright. What do you think? 🤔
i think that sounds awesome mate
More flame, less soot BUT is it providing more heat to the cooking or RADIANT heating area
yes - if there is more flame and more compete burn (less soot) it must be providing more heat
Is there a design that would fit in a traditional indoor fire place?