Jump to content
I Forge Iron

dian

Members
  • Content Count

    22
  • Joined

  • Last visited

About dian

  • Rank
    Member

Profile Information

  • Location
    - Switzerland

Recent Profile Visitors

49 profile views
  1. dian

    Flame Check

    i didnt know vinegar would remove zink. the conventional way is muriatic acid. and even then, if you have a part submerged in a sufficiantly large quantity of lets say 20% muriatic it will take a couple of hours, at least at room temperature.
  2. dian

    coca-cola burner

    one could also copy a carburetor or injection stack, but how they work with gas induction would have to be seen. anyway, the basis is the classic pipe-fitting-burner that produces a flame temperature of 2165/2206°f (45/60 psi). the position of the probe is optimised for each measurement and choke adjusted to max. temperature. as the flame tends to get hotter with time and there are some "inexplicable" fluctuations there is some scatter to the data and i took the highes achieved. my setup consists of an inexpensive instrument and probe, combined with a professional compensating cabl
  3. dian

    coca-cola burner

    cant edit post. why is that? so the drop in flame temperature was 190°f. (had to look it up.)
  4. dian

    coca-cola burner

    propulsion gasses exit on the big end. i think my coke funnel has the shape you are talking about. weirdly enough they are the only ones among all the other plastic bottles, the problem being that i dont drink the stuff. the convex shape is in the throat and the rest is there to stabilize the air (and prevent wind messing with it, as i hope). it bugged me that there was not much difference in the position of my nozzle, so i figured it might need to go deeper into the throat, leading to the tapered variety (same size orifice). this one reaches into the steel pipe itself but results were t
  5. dian

    coca-cola burner

    trying to find best position of the nozzle by replacing the choke with a cardboard-choke. i figured the smaller the opening at a constant flame temperatue the more "suction" im getting. well, it turns out the nozzle can be almost anywhere, the difference being a few degrees. i then settled on what seemed slightly the best.
  6. dian

    coca-cola burner

    this is the intake shape im trying to reproduce:
  7. dian

    coca-cola burner

    as the experiments looked promissing i started building the burner. i made the outside intake out of kitty-litter-epoxy. it runs on the slightest opening of the choke. the inside shape looks like a problem because the wall has to be very thin for the secondary air (siphon?) effect to work . im trying to find/think of something out of metal. the best so far is a thermo-bottle i have, but the throat is too big. does anybody have a good idea without me having to take up metal spinning? the shape, btw, with its parallel inlet and outlet walls is inspired by some rocket jets i cam
  8. dian

    Burners 101

    a ratio has no units. a ratio of two is when something is twice as large as something else. a pressure ratio of two means that one pressure is twice as large as onother pressure. if you have propane with a gage pressure of 15 psi the absolute pressure is 30 psi. atmospheric pressure is 15 psi, so the pressure ratio of propane in the orifice of the burner is 2 or 2:1.
  9. dian

    Burners 101

    mikey, i have recently scaned though a book my michael porter. would that be you, by any chance? yes, laval nozzle (orifice) in a lavale nozzle (burner) would be the ticket. there is a flaw, however, the flow returns to sub sonic on the exit.
  10. dian

    Burners 101

    maybe i missunderstand, but it appears that at a pressure ratio of a little over 2 the flow is sonic through an orifice.
  11. dian

    Burners 101

    interesting, because my understanding was that sonic speed at a pressure ratio of around 2 (?) was max atainable speed and the mass flow would be proportional to the pressure ratio above that.
  12. dian

    coca-cola burner

    the idea might not have been completely clear from the picture. the outer bottle neck is opened up to the id of the pipe and is attached too the pipe by the short connector. (actually there is 6° taper and a corresponding chamfer in the pipe with the edges blended in.) the inner bottle neck is closed by the choke. the air enters the pipe between the two parts through the annual opening that is properly adjusted for free air operation. as soon as the choke is opened ever so slightly, the flame goes out, so im led to believe there will be enough reserve in the forge. this tip indeed ha
  13. dian

    coca-cola burner

    hi mikey, thanks for the feedback trying to understand what you are saying: what "hole" should be 1-1.25" long? the orifice?
  14. im building a forge that should be able to get to as high a temperature as possible. so i started experimenting with propane burners. i have built quite a few burners over time for hardening or forging small pieces and most of them are adjustable to the point where the flame goes out on the lean side. i quickly found out than more air is needed in a closed chamber than in free air so the goal is to have an even larger reserve to lean the burner out. this is the prototype design i came up with: im getting a good flame with the secondary (or is it primary?) intake complet
  15. mikey, thats a very interesting recommendation, but im not sure i really get it. acute angles to the axis of the forge? so 30°? and opposing sides radially, right? and both burners on one end of forge forge?
×
×
  • Create New...