Search found 17 matches

by Narada
Thu Jul 14, 2005 2:16 pm
Forum: Valveless pulsejet forum
Topic: Autoignition?
Replies: 23
Views: 9422

re: Autoignition?

Propane's AIT is 450C, and coking should be less of an issue. But gaseous injection systems? Anyone?


http://www.itcilo.it/english/actrav/tel ... /74986.htm
by Narada
Thu Jul 14, 2005 1:29 pm
Forum: Valveless pulsejet forum
Topic: Autoignition?
Replies: 23
Views: 9422

re: Autoignition?

Greg, I wasn't thinking of keeping it cold per say, just trying to reduce the energy that escapes without being put to useful work. Simpson was before my time, so I'm not familiar with the history there, I just get the feeling that something...unpleasent happend between him and the forum members. At...
by Narada
Wed Jul 13, 2005 9:06 pm
Forum: Valveless pulsejet forum
Topic: Autoignition?
Replies: 23
Views: 9422

re: Autoignition?

Bill, I'm looking for ways to reduce the fuel consumption to the point where a "pulsejet" can compete, on a basis of thrust delivered,with a piston driven prop. Some addtional complexity is acceptable, as long as it's not as complex as available solutions (i.e. turbojets, or piston/prop). My initial...
by Narada
Wed Jul 13, 2005 9:02 pm
Forum: Valveless pulsejet forum
Topic: Autoignition?
Replies: 23
Views: 9422

re: Autoignition?

Bill,

You're right about that, coking would be a problem for liquid hydrocarbons. And injectors for propane...or methane...hmmm.
by Narada
Wed Jul 13, 2005 9:00 pm
Forum: Valveless pulsejet forum
Topic: Autoignition?
Replies: 23
Views: 9422

re: Autoignition?

Ugh...Mike...lol, those would be the dirty details. But you can adjust for it. "Just" look at the specific heat capacity of which ever fuel you plan on using, and you know how much heat it can absorb before you have to deal with it flashing to vapor as soon as it leaves the high pressure delivery sy...
by Narada
Wed Jul 13, 2005 8:51 pm
Forum: Valveless pulsejet forum
Topic: Autoignition?
Replies: 23
Views: 9422

re: Autoignition?

Bill, I don't follow what you're saying here. If you inject a stocihometric amount of hot fuel into a chamber, and it combusts, the heat released is going to result in expansion. If the chamber has a opening, that expansion is going to force the gases out of that opening. If the opening has an appro...
by Narada
Wed Jul 13, 2005 8:08 pm
Forum: Valveless pulsejet forum
Topic: Autoignition?
Replies: 23
Views: 9422

re: Autoignition?

Hmmm... So Bruno, you're telling me that if I have a chamber...a jar for example, at atmospheric pressure, just regular old air, and a spray a fine mist of kerosene which has been preheated to 700C, that it won't ignite? Cause, that's kinda the definetion of the autoignition. It's the temperture at ...
by Narada
Wed Jul 13, 2005 4:17 pm
Forum: Valveless pulsejet forum
Topic: Autoignition?
Replies: 23
Views: 9422

Autoignition?

Its silly question time! Why...do pulsejets have to have a tail pipe? As I've understood it, it's to return some of the hot combustion products to provide an ignition source. Opinons vary, but operating temperature of a pulse jet is somewhere in the vacinity of 2000F. This is well in excess of the a...
by Narada
Fri Jul 08, 2005 6:42 pm
Forum: Tools and Construction
Topic: Today's tidbits
Replies: 619
Views: 178050

re: Today's tidbits

Looky what I found at Target.....hmmmmm...what ever could I do with something like this....
by Narada
Sat Jun 04, 2005 5:31 am
Forum: Valveless pulsejet forum
Topic: Tesla's Valvular Conduit
Replies: 46
Views: 25383

Re: re: Tesla's Valvular Conduit

Mike Everman wrote:Well it's an interesting diversion but a dead end nonetheless.
You seem pretty convinced Mike, have you done some experiments with flow rectifiers? Or is there an old thread on the forum where someone has tried something similar?
by Narada
Sat Jun 04, 2005 2:19 am
Forum: Valveless pulsejet forum
Topic: Tesla's Valvular Conduit
Replies: 46
Views: 25383

re: Tesla's Valvular Conduit

I just burned all my discretionary spending money for the next six months, but as soon as I have a positive cash flow again I'll put together a crude approximation, test it and what not. I was thinking about how to do it with out a CNC lathe, which I do not have. I think I can make a reason able app...
by Narada
Sat Jun 04, 2005 2:12 am
Forum: Valveless pulsejet forum
Topic: Tesla's Valvular Conduit
Replies: 46
Views: 25383

Re: re: Tesla's Valvular Conduit

My opinion on the VC is this: The point perhaps being missed is that the effect of primary importance in the pulsejet duct is getting the partial vacuum as low as it can go. That means that you want the gasses to get out of the CC in as big a hurry as you can. This is a dead end, and if it actually...
by Narada
Fri Jun 03, 2005 4:53 am
Forum: Valveless pulsejet forum
Topic: Tesla's Valvular Conduit
Replies: 46
Views: 25383

re: Tesla's Valvular Conduit

Wow Mark! Good stuff, thank you. One of the things said in the article there brings to mind another question I had/have. Has anyone tested a lockwood or another of the rear facing pulsejets in a situation that simulates what it would experiance in flight, i.e. in a an airstream. What I'm wondering i...
by Narada
Fri Jun 03, 2005 3:16 am
Forum: Valveless pulsejet forum
Topic: Tesla's Valvular Conduit
Replies: 46
Views: 25383

re: Tesla's Valvular Conduit

Well, I agree with you Bruno, it probably isn't the most efficient containment scheme. To be honest, I kinda had the same bone to pick with the lockwood. Seems to me that a fair amount of energy must be lost when the flow goes around that 180 degree bend. I wonder if there is a large enough body of ...
by Narada
Thu Jun 02, 2005 4:29 pm
Forum: Valveless pulsejet forum
Topic: Tesla's Valvular Conduit
Replies: 46
Views: 25383

Tesla's Valvular Conduit

Ok, I'm not sure if this should actually be over in the valved pulsejet part of the forum or not, and maybe it's already been covered. Tesla, way, way back in the day, came up with this ...flow diode. Theoretically would allow flow in one direction and restrict flow in the other direction. I came ac...