dagabu Posted April 2, 2012 Posted April 2, 2012 I had NEVER even heard of whistle endburners before last week so I had to go across state lines to the land of Cheese to check them out. I found out that you can double or triple the power output from your endburners by simply using good fast whistle fuel instead of BP. Here is one filmed by my son, he cut the video off about 10 seconds too soon right about the time it punched through the cloud deck at 1400'! There was a good 6 second delay from the time the sky all flashed white to the noise. What a treat! http://www.youtube.com/watch?v=loXCHv5Dq-s -dag
dagabu Posted April 2, 2012 Author Posted April 2, 2012 That is with standard endburner tooling with a full clay nozzle! Yes, the whistle fuel will whistle but I cut it with 5% charcoal for a tail, that is enough to cut the whistle. -dag
Mumbles Posted April 2, 2012 Posted April 2, 2012 Have you tried them without the charcoal to see if they make any noise still? I think it would be interesting to know. One of the theories behind whistle production is that the oscillatory burning of the fuel resonates in the empty cavity of the tube. Having a choke there could disrupt that, and could give some merit to it. Granted, this is one of the more well accepted theories, but it's always interesting to see it in action.
dagabu Posted April 2, 2012 Author Posted April 2, 2012 Yes, indeed it does whistle but the video showing it (and hearing of it) isn't mine to show here. Let me see if I can get permission to post it first. The whistle is not loud as it is choked and it does take a second to make the cavity behind the nozzle but is is there. -dag
drthrust Posted April 2, 2012 Posted April 2, 2012 (edited) great post Dag, whistle end-burners, its so simple i cant believe its not been done before,exciting times Edited April 2, 2012 by drthrust
Mumbles Posted April 2, 2012 Posted April 2, 2012 It has been done before. I've had the tooling diagram from Steve LaDuke for 6 years. I guess I always just assumed it was kind of common knowledge.
dagabu Posted April 3, 2012 Author Posted April 3, 2012 It has been done before. I've had the tooling diagram from Steve LaDuke for 6 years. I guess I always just assumed it was kind of common knowledge.
WonderBoy Posted April 3, 2012 Posted April 3, 2012 (edited) I haven't had the diagrams as long as Mum, but I too AssUMed it was common knowledge. There are a couple threads on Passfire that I had saved, haven't found them again yet, that gave more information on these and outlined some reasoning for using a mix of BP with whistle for the fuel instead of straight whistle. I can't recall what they were, as we just lost the championship game, but maybe I will find them tomorrow. WB Edited April 3, 2012 by WonderBoy
dagabu Posted April 3, 2012 Author Posted April 3, 2012 The really interesting thing is that the use of hot whistle has some real lifting capabilities, I an putting a 2" shell on top of a 10 increment whistle end burner this week and will be adding them to my thrust testing I will be doing soon. Right now, I see suggestions that these little endburners are producing 10# of thrust for up to 14 seconds or as long as the nozzle or tube holds. Either way, this is going to be fun. -dag
FlaMtnBkr Posted April 3, 2012 Posted April 3, 2012 Potassium chlorate is supposed to make significantly hotter fuel than perchlorate. Do you think doing a combination of everything to increase power would make a fuel that can be used in a nozzle-less endburner? Use chlorate with a copper oxychloride catalyst in a 76-23-1 ratio? I guess if it still whistles using a nozzle then all that isn't needed, assuming you are looking for a whistle and not just a high performance fuel. I guess I just like the simplicity of nozzle-less rockets. I don't know if a hotter fuel also means a more sensitive fuel so that would be a concern and some sensitivity testing done. I'm thinking of mixing some just to try and get a dark report. I imagine benzoate is safer than sulfur and antimony with chlorate.
dagabu Posted April 3, 2012 Author Posted April 3, 2012 Potassium chlorate is supposed to make significantly hotter fuel than perchlorate. Do you think doing a combination of everything to increase power would make a fuel that can be used in a nozzle-less endburner? Use chlorate with a copper oxychloride catalyst in a 76-23-1 ratio? I guess if it still whistles using a nozzle then all that isn't needed, assuming you are looking for a whistle and not just a high performance fuel. I guess I just like the simplicity of nozzle-less rockets. I don't know if a hotter fuel also means a more sensitive fuel so that would be a concern and some sensitivity testing done. I'm thinking of mixing some just to try and get a dark report. I imagine benzoate is safer than sulfur and antimony with chlorate. I have no interest in the whistle sound, just the power available. I don't use chlorate as I use ammonium fuels. -dag
vegasdude Posted April 3, 2012 Posted April 3, 2012 Hey Dag, if you are on using 10 increments does this mean your tube length is around 4" to 5" ?
dagabu Posted April 3, 2012 Author Posted April 3, 2012 Hey Dag, if you are on using 10 increments does this mean your tube length is around 4" to 5" ? Actually, I have standardized my 1# tubes at 6" long since I dont use the full length BP spindles anymore and use them as is for all my 1# rockets. 10 increments is 10 rounded teaspoons (not heaping) of comp or about 3.5" of comp when all is said and done. That leaves about 1.5" of room for report. -dag
mabuse00 Posted April 3, 2012 Posted April 3, 2012 the tooling diagram from Steve LaDukeI'd like to know some details, if you don't mind sharing. Did they use a larger nozzle?
dagabu Posted April 3, 2012 Author Posted April 3, 2012 I'd like to know some details, if you don't mind sharing. Did they use a larger nozzle? I have not seen Steves tooling but I use standard end burner tooling and make them the same way. Best yet, I am using the cheap/pulpy tubes for these and if I do use a faster whistle some day, I will use NEPT tubes but for now, these work very well. Now, I wonder what these will do in a girendola? -dag
Mumbles Posted April 3, 2012 Posted April 3, 2012 Now that you mention it, the diagram is almost identical with normal end burner tooling. They differ by at most a hundreth of an inch or so from what the Rocket tool sketcher spits out. That is probably more Steve rounding to convenient numbers than anything.
Juiceh Posted April 3, 2012 Posted April 3, 2012 (edited) Last August I pressed a short whistle endburner using Ben Smiths super BP endburner tooling. It was really just to mess around and see what would happen. I had always heard that whistle fuel doesn't whistle behind a clay nozzle, and that if you put a nozzle in front of whistle it would CATO anyway... I used more pressure after the clay, so the first increment of whistle as it was consolidating it also consolidated the clay further down the spindle and thus enlargening the nozzle some. Normally using higher pressure higher up the spindle is a bad thing due to cracking the fuel grain below, but it didn't seem to cause an issue with the clay(plain bentonite). The motor tube was only about 2 inches tall possibly slightly less, I don't recall. The whistle around the spindle was Dan Thames whistle super fuel with CuBenz subbed for the Nabenz. About 1/3 inch above the spindle I switched to red iron 76:23 sally fuel and topped it off with a small report. I really did not expect it to fly. http://www.youtube.com/watch?v=YBAWD0szslU Edited April 3, 2012 by Juiceh
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