Propane Burner design

[steamntrout]

I am converting a small 1" scale boiler from a coal fired boiler to a propane fired boiler, and have been working on developing a propane burner. I have come up with several workable designs, only problem with them is that they are too tall. When I shorten them to the height I want the jet size relationship to the air opening changes dramatically. (Been using a regulator to control the gas pressure.) I have searched the net a couple of times looking for guidelines for the air to gas relationship and have not had any luck.

This site and the Practical Machinist site have given me great results in the past & I hope again will lead me to the desired solution.

[oldtiffie]

Any of this help?

http://en.wikipedia.org/wiki/Propane_(data_page)

http://www.backyardmetalcasting.com/oliverburner1.html

http://www.vk2zay.net/article.php/81

http://www.youtube.com/watch?v=dao-612LVBA

http://www.google.com.au/search?hl=e...&start=10&sa=N

[Swarf&Sparks]

Steam, dunno if this will help, but try some of the home foundry sites.
Google "reil burner" for starters.

Bit of coincidence here, I'm on the way to getting my first boiler built.
AS3902, ASME9, hydrostat, etc, etc, etc............
Will be oil fired (Babington)

edit to say
another great board is
http://www.homemodelenginemachinist.com/index.php

I've been lurking there for a while. Now my main comp is back up, I'll introduce myself.

[steamntrout]

Thanks for the suggestions & various sites to check out, seems that the majority of these folks are building a burner for foundary purposes or the site provides general properties of various fuels such as their heat product. What I am looking for is information on;
Jet size and air opening size (Have found that it makes a difference)
Jet location with respect to air opening (Have found that it makes a difference)
Length of burner (from the jet) (Have found that it makes a difference)

I have made a very successful burner that is made as follows:
1/8" pipe that is 1 5/8" OAL length
It has a cap with (6) .047" Wide X 1/8" long slots at the top
It has a jet of .028" dia with (3) .187" dia 'air' holes adjacent to the jet outlet
It runs beautifully at 1-2 psi on the propane and provides a 3 1/2" dia blue flame with a tinge of orange.

The problem is that I want to shorten the burner to a 1 1/4" OAL and just doing that it throws every thing out of whack. I just have this belief that somewhere someone has developed the relationship between the jet size (area), the air opening (area), and the length of the mixing chamber (area)(from the air holes to the burner openings) and burner openings (area).

OK OK you probably want to know why I want to shorten the burner right?
Well my boiler has a firebox that is 5" W X 9" L and 5" Bottom to Top of the crownsheet, I want to heat all of the side legs of the boiler not just at the tube height, and because is is a 1" scale Little Engines locomotive there is insufficent room to drop the mainfold any lower.

I'll continue to expirement and will post the results with photos of the various tests.

In the mean time one of our late members Marty Siegel came up with a very successful burner (the genesis of this design) that many have used with great success check it out at www.ggls.org

Ken

[Weston Bye]

There is a lot of discussion on the Live Steam & Outdoor Railroads BBS about the topic.

This thread can give you a starting point:

http://bbs.livesteam.net/showthread.php?t=967

[JimH]

Jerry Howell sells plans for a small bunsen burner that works very well on low pressure propane. If I remember correctly, it is somewhere around 1 to 1 and 1/2 inches tall without the base.

http://www.jerry-howell.com/

Jim