SparkGunSearch
03/10/04
So today I played around with making a torch that ran off alcohol. Was fun and scary.
Setup: A recycled windshield washer pump and reservor and a 12V gel cell to provide a source of denatured alcohol under pressure.
A 12 DV blower with a DC motor speed controller to provide a source of air.
A brass pressure washer spray nozzle and a torch made out of 3/4 black pipe.
Result: While the spray nozzle did an okay job of generating a fine mist, the alcohol tended to pool in various parts of the apparatus.
This was kind of scary since you could hear alcohol bubbling in the torch and the flame was not quite right. I wasn’t able to get a smooth flame that burned smoothly. And there was always some alcohol pooling in the plumbing somewhere. At high fan speeds burning drops of alcohol would be ejected from the torch.
Explanation: This setup didn’t have a vaporizor. It turns out that it takes 396 BTU/lb to vaporize alcohol. With a 9/1 air to fuel ratio that means that 1 lb of fuel-air needs 39.6 BTU to vaporize the alcohol.
03/25/04 Used a section of 1/2 inch stainless steel flexible gas hose for the air line. I looped it over the top of the torch and started playing with it. The results were okay. The torch heated the air in the 1 inch section of the hose that was in the flame enough to vaporize the alcohol.
Pictures
Other interesting bits is that the pump is leaking. Hmmm…
I suspect that if I want to continue along this line I need to purchase a small dc gear pump that is designed for alcohol. Fortunately Cole-palmer sells one for about 45 clams.
03/28/04
I’m in the process of constructing a torch with a regnerative heater built into it. The fun part is welding 20 gage sheet metal which is kind hard but good practice. Also first real use of my slip roll and brake.
Results sucked ass, the design of the torch made it such that the flame wanted to burn outside the torch. This meant that there was no preheat at all. Which sucks ass.
04/20/04
Got the Turbocharger in today. The turbine part is big and ugly. Hmmmm More stuff to play with.
Okay more thoughts. I’ve been using direct alcohol injection which hasn’t worked very well. I think what I need to do is two fold. First design a premix system that produces a solid alcohol flame that heats an evaporator coil to heat the alcohol.
Second use a seperate blower for feed the snazzy fuel into the flame. A potential test would be to use the neon burner setup to supply a good premix of air and fuel to a duel fuel torch, spray alcohol and air into the torch after the preburner.
05/02/04
Used the lathe to make a fitting to turn a 1” diameter pipe into a nozzle. Propane injected in the bottom, air + dust through the side of the 1” nozzle. Worked much better than before. Then I jammed a 2” diameter pipe over the whole thing. Wozza! The flame stays inside the pipe at all times.
Next to do. Design a 2” diamter burner. The idea is to have 6 propane injector holes around a central air hole. Fitting should be made of steel and then welded to the inside of a 2” diameter pipe nipple.
05/06/04:
Yesterday I put together the new manifold for the spark gun. Has a 0.45 diameter hole for air and six 3/32 diameter holes for propane.
Propane was fed using a torch valve and the air fed using the blower with speed control as usual. The result was very good. The flame was stable over the entire operating range. You could run the blower full blast and the flame didn’t go out. Is good!
Tossing charcoal powder into the blower produced a nice tower of sparks. Metals produced good sparks except for the spherical titanium. The blower has a lot of trouble moving this stuff. The last attempt was to dump a metric buttload into the fan which stalled it and blew titanium into the motor itself. Blower is now in heaven.
Next task is to buy a motor for the turbo charger fan and try it out. Other thoughts are to try and design and build my own blower, with an eye towards making a blower that can deal with heavy loads of powders. —-