Ted Ewert

Here was the first burner I made:

Then added a new top with holes drilled at an angle to create some swirl

At this point I didn't understand the pressure / flame / size-length of pipe relationship (as you can see the flame burning up in the head). This was part of reason I went to a blown design. I could revisit this burner, and with a few minor modifications, make it work quite well. 

This was my first blown design. It worked all right, but with a 3/4 inch pipe didn't deliver a very hot flame.

Here's what it looked like in the forge:

This was my version of a ribbon burner. I packed Kaowool between the tubes and then put a 1/2" insulating board on top of that with holes for the tubes. It stayed pretty cool.

Here's a pic of it in the forge. I put some stainless steel screen over the tubes to keep the flame lit and up close to the top of the forge.

Somewhere in the mix I built this total failure. It has no compression / acceleration of the gas and as a result the flame burned up inside of it. But it was a good learning tool.

I then caught on to the compression /acceleration trick and built this head:

But, as you can see in the picture I still had the flame burning up in the head and getting everything hot.

I use threaded rod to provide turbulence. This slows down a portion of the mix and helps to keep the flame lit as the velocity of the gas increases.

The last head I made was a culmination of what I have learned so far:

The piece sticking out of the hole is the edge of an airfoil. Picture an airplane wing and this would be the trailing edge. The gas passes around it and gets compressed and accelerated on each side. This forms it into a thin, wide flame. BTW, this shape doesn't work without the airfoil. The bolts are there to adjust it in and out to see how it works with varied flows.

Here it is burning in free air. Notice how the flame starts at the threaded rod. I ran this for about 5 minutes and it was cool to the touch. It also burns the same in the forge.

I'm thinking of using something like this in the new forge I'm building. It would lend itself to a nice tangential burn in a cylindrical chamber, and create a decent swirl.

Ted

I'll give you a little background where I'm coming from. I like to build things, and metal is my preferred material. I started off building a small anvil, then decided to put a harder surface on it and purchased a 1/2" thick  piece of D2. I knew D2 was tool steel but that was about it. I then discovered all about heat treating and figured I'd build a little HT oven. I built it out of standard firebrick and mortar. Then I learned all about refractory materials (do you start to see a pattern here?). So I have this brick and mortar boat anchor, and get the bright idea to turn it into a forge. Drill and cut a few holes in it and Bob's your uncle. I took apart an old propane burner I had for a still I made and used the nozzle in a few NA burners I fabricated. The regulator was junk, so while waiting for a new one I started messing around with blown burners, since I happened to have a blower. I went from 3/4" to 1" pipe, then to 2". This is fun! I made round flames, wide area flames (with a ribbon burner) and recently made long thin flames. 

I've studied a bit about fluid dynamics, am quite familiar with Bernoulli, Coanda and have read a lot of Victor Schauberger (among others). I don't, by any means, claim to know much about forges or burners, but I'm getting the hang of it. I'll post a few pictures tonight of what I've made so far and let you guys have at it. 

Ted

I haven't read the whole 45 pages of this thread, but I was wondering if blown burners would be allowed into the discussion? I've been experimenting with several different designs and would like to talk theory a bit. This is the only forum I've found which actually dives beyond " it lights up and it's hot...I'm good to go". 

Ted