3D printed plastic burner experiments (photo heavy)

[Mikey98118]

I would try for only three fins. Even thin inner faces on fins create some turbulence. Turbulance creates drag. Eight edges may create too much drag for too little gain in swirl; just a thought

[Another FrankenBurner]

22 hours ago, Frosty said:

While I was able to make a strong vortex the device had a weak flow. 

I think this will always be the trade off.  The vortex taking energy, leaving less for the rest of the work.  Another balancing act of encouraging just enough vortex to aid in mixing while using as little energy as possible.

22 hours ago, Frosty said:

My thoughts may not have enough information behind them to count for much.

Thank you for sharing them.  They have helped with my understanding of things.  My observations all line up with your thoughts.

22 hours ago, D.Rotblatt said:

Just kind of thinking out loud here...

It's a great thing to do here.  I am now playing with streamlining the reducer shape as much as possible, minus the vortex vanes.  It's a complicated thing as OD, length, and curve geometry are all in play.  Once I get as much air induced as I can, I will then add vortex encouraging vanes again.  I want to put them into a forge to see the pro's and con's of each.

22 hours ago, G-son said:

I have yet to meet one of those engineers, the one I've talked to didn't have that habit.

I didn't not mean to imply all engineers are this way.  In my line of work, engineers are the only "experts" I deal with.  Lots of them are great.  Some of them are inflated.  I usually get into the problem areas when reality doesn't match up with what the book says so then I have to question what I am told.  

22 hours ago, G-son said:

The drawing is close to what I'm thinking. A little longer vanes to increase overlap, and a bit taller vanes to increase inlet area past the vanes to reduce the risk of restricting the flow there, and it's perfect!

How about this guy:

Or would you like to take Mikey's suggestion of dropping to 3 vanes?

19 hours ago, D.Rotblatt said:

I’m thinking that a sand cast of your burner head is absolutely doable

I am going to do some experiments to work towards this.  Trying to thread the vanes out of the core is my only concern.

[G-son]

2 hours ago, Another FrankenBurner said:

 I usually get into the problem areas when reality doesn't match up with what the book says so then I have to question what I am told.  

How about this guy:

Or would you like to take Mikey's suggestion of dropping to 3 vanes?

When the reality doesn't match how things are supposed to be you can generally be sure there is SOME kind of problem going on. Human error may be the most common kind, and not all humans like to admit they were wrong.  

The picture is perfect for what I had in mind, I really like it. At the same time, Mikey generally has a good idea what he's talking about. Probably best to go with the three vanes.

[D.Rotblatt]

12 hours ago, Another FrankenBurner said:

Trying to thread the vanes out of the core is my only concern.

I’m using sodium silicate and sand for a core. It sets like sandstone, so if there’s a draft on the fins they’ll pull out easy. 

DanR

[Mikey98118]

I have heard that sodium silicate glued sand cores can run from "crumbly" to hard (and even harder to remove). Has anyone ever tried vibration to break a core down?

[D.Rotblatt]

4 hours ago, Mikey98118 said:

 

I have heard that sodium silicate glued sand cores can run from "crumbly" to hard (and even harder to remove). Has anyone ever tried vibration to break a core down?

 

Too little sodium silicate, wrong sand, or let it sit out too long (it’s hydrphilic), and it will be crumbly. Vibration not so great, dissolves like snow under a stream of “hot liquid” when sandblasted.  

DanR

[Frosty]

On 9/11/2019 at 6:48 AM, Another FrankenBurner said:

How about this guy:

Rendering snipped, it's the one 4 posts back. You're welcome for the bandwidth. 

I think something like that is what it'd take to actually induce a vortex and it's pretty close to what I was thinking though without the air foil shape, just flat vanes. I envisioned larger gaps between vanes or inner and outer shells. 

To make that work I think the disk structure shown as the floor of the vanes in the picture needs to be wider to provide enough space between vanes to allow free intake. Take a tin can 2" dia and another 3" dia Cut them in half lengthwise. Bend a gentle outward curve to one edge of the 2" halves. 

Off set openings in the outside shell so they touch the outward curved edges of the inside shell. Where is the gap for air to enter? The shells are placed farther out than the can's diameter say an added inch of radius. The openings and space between shells needs to exceed the area of the beginning of the intake trumpet.

That's just my dented musings. 

In reality I think there's more than enough random angular momentum to provide a strong vortex and it'd be a LOT easier to give it more distance to build speed than try and force it. 

Envision a description of my mental image for a minute if you will. Remove the vanes from above rendering, enlarge choke plate to match diameter, both flat to the point the trumpet flare begins. The choke plate restricts inflow which accelerates it. conservation of angular momentum and Coriolis effect induce vortical motion. The greater area of the larger intake means a larger volume of random molecules but the greater distance allows a lower energy conversion to vortical motion. Greater vortex velocity can't be avoided which means lower pressure in the eye and stronger induction.

Hmmm?

Frosty The Lucky.

 

 

[Mikey98118]

3 hours ago, D.Rotblatt said:

Too little sodium silicate, wrong sand, or let it sit out too long (it’s hydrphilic), and it will be crumbly. Vibration not so great, dissolves like snow under a stream of “hot liquid” when sandblasted.

If you are talking about fired cores doing so--after casting--that's great.

[D.Rotblatt]

A quick pictorial of some more tests.  First set with the NA ribbon burner out of the forge. 5 lbs, tip size and reducer written on tape.  Upshot, Funnel A or B worked best.  I went with 'A' for a bronze pour as it is "good enough" for now.  The wide funnel reducer was tried with a choke with no fins, and 2, 3 and 5 fins.  All created a poorer flame then any of the other ones.  There was definite vortex motion of the flame leaving the nozzle on all the finned versions, with more vortex produced by more fins, but smaller flame as more fins were added...i.e. there was a cost to inducing vortex.  The vortex could be seen by looking down the nozzle when lit, and the flame straightened as soon as it left the nozzle.

Here's the reducers tested:

_________

The chokes with the fins shown in the bottom are sized and used on the "wide funnel" burner.  The wider shape is intened to allow more air to be induced.  All but the last are with .046" mig tips shortened to about 1/4" long.  This made a huge difference between the same mig tip .675" long.   The flame color is weird on my phone camera.  I adjusted the choke in each for the best flame I could.

_________

This is the straight sided reducer with the old choke, which is wider then the new choke in used with the same reducer in the next pic.

_________

_________

_________

_________

_________

_________

_________

_________

__________

This is using the no fin choke with a .052 mig tip.  The flame was a bit rich, so this tip was too big.

DanR

=======================================================================================================

9 minutes ago, Mikey98118 said:

If you are talking about fired cores doing so--after casting--that's great.

Yes, that's correct.  Sandblasting after casting.  Since it's a sandcast the cores are never really fired in this case.  This stuff is nothing compared to ceramic shell, that stuff is awful to get out; sandblasting, needle hammers, hammer and chisel, whacking the piece with a hammer to fracture it out - nothing works very well.

DanR

 

[Another FrankenBurner]

On 9/11/2019 at 11:39 AM, G-son said:

The picture is perfect for what I had in mind, I really like it.

It's your idea, let's stick with the original first.  After that we can try 3 vanes on version G2 if you like.  I will have to try Frosty's no vanes idea as well.  

10 hours ago, Frosty said:

That's just my dented musings. 

I am having a hard time picturing this one.  I think I follow with the cutting of the cans and offsetting the outside shell.  I get lost at the point of adding this to the reducer and how the air enters.  

6 hours ago, D.Rotblatt said:

A quick pictorial of some more tests.

All very awesome.  From what I can see, it is hard to discern improvements.  They all look like serviceable flames.  

I like the contrasting flames of the Funnel A/New Choke and the 5 fin choke.  The Funnel A/New Choke picture shows a flame that is darker blue, straight, longer, and more pointed.  It is moving faster and it's secondary flame is straight and more transparent.  The five fin choke picture shows a lighter blue flame, which is shorter, more cylindrical/blunt, and a secondary which is larger, fluffy and has rotation.  The flame is moving slower.  The nozzle is hotter in the vortex flame burner picture, which may be responsible for what looks like more secondary flame.  I have seen the secondary flame go from invisible to highly apparent once the nozzle heats up.

In actual forge use, as a single port burner, I am not sure which flame type would perform better.  According to the burner technical papers, a flame which is burning shorter/smaller (provided the same fuel amount) is liberating more heat per flame area, it's hotter.  This is assuming the flames are burning the fuel efficiently.  With the larger secondary of the vortex flame, we don't know if this is the case.  

My mind is churning with new things to test, this stuff is great.  Thank you for posting.  I saw the original post with all the ribbon burner tests as well, I would be glad to have any one of those heating my forge.  

[D.Rotblatt]

23 minutes ago, Another FrankenBurner said:

In actual forge use, as a single port burner, I am not sure which flame type would perform better. 

I'll do a temperature test in the forge and see which one is better.  I was going for larger flame, but you may be right about a shorter flame working better assuming efficient burning.  That's why the ribbon burners work so well, very short flames which allow complete combustion in a short area. 

DanR

29 minutes ago, Another FrankenBurner said:

I saw the original post with all the ribbon burner tests as well, I would be glad to have any one of those heating my forge.

It's working great.  I'm going to rebuild the gun ribbon burner in my larger forge to be a 10 x 3.5" with 250-350 1/8" holes burner coming from the top of the forge (it's a crayon sized hole one coming from the side right now).  I was forge welding with it a few days ago and I didn't realize how well my little NA burner (from the pictures) was working.  I was really having to crank up my large forge, and it wasn't really reaching the heats that the smaller NA was.  The beauty of the small holed ribbon burner is that even a large burner can be turned down to really low pressures and still work.

DanR

[Another FrankenBurner]

The front half of vG1:

It is very cool looking.  It's air entrainment is pretty low as expected.  More power to the vortex is obvious in the flame.  It is a squat wide rotating flame.  It is a bit mesmerizing to watch the secondary flame dance about.

[D.Rotblatt]

2 hours ago, Another FrankenBurner said:

It's air entrainment is pretty low as expected. 

If you want vortex, you got it!  Looks pretty cool.  Now to balance it with the maximum air entrainment.

Two thoughts: What about making them taller?  I've observed that the air moves fastest down the center around the MIG tip.  If you look at side draft burners like Frosty's 'T', the opening is pretty large/high.  Making them taller allows for less of an angular flow.

Second; You could also angle them in towards the center a bit more and use a few less of them which would open the gaps. I think Mikey was suggesting 3.

Just my thoughts.

DanR

[G-son]

Well, there's a lot of rotation visible in that photo, really interesting! A short and wide flame could be useful sometimes - if the performance in other ways is good enough of course. 

[Another FrankenBurner]

This first version was made to match G-son's mental image.  It is a perfect example of the need to encourage not force a vortex.  We successfully increased the vortex energy.  In doing so, we decreased the entrainment energy.  This will always be the case and has a balance point.  We want to use as much energy for air entrainment as possible while only using as much as needed for the vortex to do what we want it to do.  We can find the most efficient way to give the vortex energy and then find the balance point.

We can make the vanes taller and/or decrease the quantity to increase the inlet area which can induce more air but as we increase inlet area, we decrease air velocity.  We want this, as any restriction that increases velocity is decreasing total air entrained.  The downside is that as the velocity lowers, the momentum decreases which makes it's path much shorter to the low pressure zone.  

It sounds like we are going to 3 vanes for vG2 and possibly taller vanes for vG3.

One thing I can say about this version, the radiant energy felt on my face while standing near this thing is much higher than the versions concentrating the flame forward.  It makes me wonder how the vortex flame will act inside a forge.

[G-son]

38 minutes ago, Another FrankenBurner said:

It sounds like we are going to 3 vanes for vG2 and possibly taller vanes for vG3.

One thing I can say about this version, the radiant energy felt on my face while standing near this thing is much higher than the versions concentrating the flame forward.  It makes me wonder how the vortex flame will act inside a forge.

Sounds like suitable development.

That also makes me wonder how the vortex flame would work for general heating outside a forge too, as in hand held burners and similar equipment. Granted, you wouldn't want the heat to radiate away to the sides where you're not heating something, but you'd also not want too much of the heat to "blow away" with the moving flame as it has gone past what you try to heat.

You could try setting metal wires through the flame at different distances from the burner, perhaps at ½" steps. Not extremely accurate, but the glowing color of the wires would give an idea about how hot the flame is, or how hot different areas of the flame is. It's a simple test that has shown me what area of the flame on my (bought) hand held burner to use, there seems to be a lot of temperature difference between different areas. 

[Phil K.]

Wow, missed this thread. I'm reading as fast as I can. Were there any STL's posted? I would like to try some tinkering as well.

[Mikey98118]

My early Mikey burners had short bushy flames, which were lengthened by extending the mixing tube a little more, Way back then, I was worried about making absolutely sure of flame stability, and shortened flames were not considered an asset in tunnel forges. Thus, Frosty used the eight diameter rule of thumb and I use nine diameters. The point is that balance in burner flames come from small changes; a feather weight on the scale--not a foot

[Another FrankenBurner]

Version G1 runs rich with the 023 tip.  The flame is a bit unwieldy and dispersed for a hand torch I would think.  If the orifice size were better matched, the flame would be smaller and shorter.  Maybe useful if wider area lower outputs were needed.  Though I wonder how stable the flame would be if we started to lean it out.  

Welcome aboard Phil.  No STL's have been posted.  If you are good with CAD, read though some of the pages and you can get a good approximation as a starting point.  

Here is v73 in aluminum.  Still needs the investment cleaned off.  He is a 3/8" guy.  You can see the misalignment spots from the 3D print in the surface.  

[D.Rotblatt]

14 hours ago, Another FrankenBurner said:

One thing I can say about this version, the radiant energy felt on my face while standing near this thing is much higher than the versions concentrating the flame forward.  It makes me wonder how the vortex flame will act inside a forge.

A short flame with dispersed heat might be just the ticket for a forge.  Apart from the radiant energy going out the doors, a lot of heat in a forge is the radiant heat from the walls and this type of flame would heat a wider area.  Also the short flame will keep air off the metal preventing oxidation (scaling).  I'm interested to see how it does in a forge!

22 minutes ago, Another FrankenBurner said:

Here is v73 in aluminum.

I love a good investment cast...you can see all the lines from the 3D printer!  FYI: If you want , you might try spraying the print with lacquer or shellac to even up the surface (we used that for waxes of sculptures to fill pinholes, etc before investing). 

DanR

[Frosty]

On 9/14/2019 at 7:38 AM, Another FrankenBurner said:

This first version was made to match G-son's mental image.  It is a perfect example of the need to encourage not force a vortex.  We successfully increased the vortex energy.  In doing so, we decreased the entrainment energy.  This will always be the case and has a balance point. 

This last statement is incorrect. It only applies to a tubular mixing tube. 

The stronger/faster the vortex the lower the psi in it's center (eye). Enlarge the vortex and eye increases the vac to ambient differential and being larger the eye's cross section increases geometrically making more room for intake air.

Old style tapered burners have significantly stronger induction. When I worked with them in road maintenance I took a damaged one apart and replaced the crunched mixing tube with straight pipe and had to reduce the dia of the jet significantly to even get it to light and it never produced a tuned flame. Being burners means commercially built ones are always linears, Jet ejectors are for something entirely different.

The reason a strong vortex makes a shorter flame is because the flame isn't exiting in line with the tube's axis. I think this is highly desirable in a forge/furnace, keeping the highly chemically active flame off things is a good thing. No? Following that logic I think an ideal burner furnace combo would see complete combustion before a flame can touch anything in the furnace. 

Frosty The Lucky.

[G-son]

4 hours ago, Frosty said:

Old style tapered burners have significantly stronger induction.

What design are you referring to? I haven't had the opportunity to look closely at very many large commercially built burners. I assume there has been many designs around, many perhaps more because of easy/cheap construction than best performance.
And, are you saying that ditching the straight tube for other shapes can be a big step up in performance/efficiency? Or is it one of those cases where you get one improvement at the price of loosing something else?

[Frosty]

Straight, plumbing pipe burners have been around, that I'm aware of, since around the American Civil war. However linear burners almost undoubtedly much maybe millennia longer. Old gas lamps have as Mike's been calling them Wasp wasted burners.

A good enough plumbing pipe burner is really cheap and doesn't require special tooling so if folks will buy them a maker would have to be a fool to try selling high performance "Wasp wasted" ones. Hmmmm?

To answer your second question.YES a mixing tube tapered in the below manner makes a significantly more effective burner. 

The one pictured below is IIRC about 30 years old the throat of the burner is under 1/2" dia. I didn't measure it but a 1/2" round bar is stopped cold. It easily brings this forge to welding temperature with that much opening. Mark only lights the other one when he's in a hurry, say shoeing. The one shown is the equal of the 3/4" Ts I make and please note the jet on the blow burner isn't even aligned, it should be much hotter than it is.

Frosty The Lucky. 

 

[Another FrankenBurner]

9 hours ago, Frosty said:

This last statement is incorrect.

I stated what I meant quite poorly.  I did not mean to imply stronger vortex and more air induction can't be had together.  All I meant was the more energy spent on vortex, the less there is available for induction.  Energy in = energy out.  The wasp waist burner is a great example of using that energy more efficiently.  Do you suspect that the reason the wasp waist does so well is because it promotes stronger vortex or simply because of the drop in resistance?

10 hours ago, Frosty said:

Following that logic I think an ideal burner furnace combo would see complete combustion before a flame can touch anything in the furnace. 

Maybe ribbon burners are superior because of their shorter combustion zones? 

For a single port, I am picturing some kind of fire tube between the burner and the forge.  A nozzle extension of sorts.  

3 hours ago, Frosty said:

Mike's been calling them Wasp wasted burners.

When I first heard the term, I did some googling.  I found a bunch of corset styles.  At the time I assumed it was where the term came from because of the likeness of shape.  WIkipedia Wasp Waist.

3 hours ago, Frosty said:

The one pictured below is IIRC about 30 years old the throat of the burner is under 1/2" dia.

Those look extremely long compared to most of the commercial wasp waist burners I have seen.  Quite neat.  I will have to get some pictures of the burners I see quite often.

Today was a good day.  Our first successful iron cast:

The three little nibs are from pinhole air vents.  We were not hot enough previously.  We up sized burners:

The top is one of our first investment casts, the bottom is burner was cast yesterday.  It is another experiment.  The casting has improved a bit.

With more btu's and more patience, the metal was a bit hotter this pour:

Here is another shot from the bottom after some machining.  It still needs a bit of work.

[G-son]

9 hours ago, Frosty said:

A good enough plumbing pipe burner is really cheap and doesn't require special tooling so if folks will buy them a maker would have to be a fool to try selling high performance "Wasp wasted" ones. Hmmmm?

To answer your second question. YES a mixing tube tapered in the below manner makes a significantly more effective burner. 

The desire for a lathe just keeps getting stronger, and the parts casting we see here may be an other way to some really potent home built wasp waist (or new style) burners. The future will be interesting.

I would think that there's always people who want to buy (or build) the cheap & "good enough" equipment, and a few that want the best possible, even if it costs quite a bit more. Higher performance has also always been a good selling point. But sure, at a suitably higher price to match the higher manufacturing cost the wasp burners probably wouldn't sell in very large numbers, and many would perhaps not bother to develop and make them just to sell a few.

The gas jet size will have to be quite a bit bigger in a waist style burner than a straight tube burner of the same diameter, to match a larger amount of air, right? Or to flip it around, you need a smaller waist to the same size gas jet.

I'm thinking I may have to roll some sheet metal cones, for waisted burner tests… Hmm.