Search found 111 matches

by jmhdx
Mon Oct 11, 2004 7:06 pm
Forum: Valveless pulsejet forum
Topic: M1E Preview
Replies: 49
Views: 21140

Re: M1E Preview

Does anybody know the speeds of sound at say 500,1000,1500 degrees centigrade? I had thought that the pheonix b.c.v.p engine failed to run for more than a few seconds(or was it less) because the mean tube temperarture had increased making the tube effectively too short when hot. Not so critical in o...
by jmhdx
Mon Sep 27, 2004 7:10 pm
Forum: Valveless pulsejet forum
Topic: Focused wave engine runs!
Replies: 127
Views: 82798

Re: Focused wave engine runs!

Hi all, thought it was time I chimed in with my unqualified and often worthless opinion. Are we forgeting what the "exhaust" is for? A reynst pot or jam jar relies solely on rapid cooling and therefore contraction of the remaining gases in the chamber for refilling by the then higher pressure of the...
by jmhdx
Wed Sep 22, 2004 7:44 pm
Forum: Valveless pulsejet forum
Topic: Focused wave engine runs!
Replies: 127
Views: 82798

Re: Focused wave engine runs!

Congratulations on another successfull build Steve, I was quite exited by the title Focused Wave Engine Runs but then remembered the breif. Not a bcvp or some other wizardry but a practical attempt to find an effective combustion chamber form. In that respect its a success and comparative measuremen...
by jmhdx
Tue Sep 14, 2004 5:31 pm
Forum: Valveless pulsejet forum
Topic: The simplest pulsejet ever
Replies: 28
Views: 11760

Re: The simplest pulsejet ever

I love an elegant solution, less is more, I hope it works and can see no reason why it couldn't be made to resonate, but you know how fiddely these things can be. You right about the minimum 4" tube as it would be difficult to get the air/feul mix right on a smaller model. I've never seen a reyns't ...
by jmhdx
Thu Sep 02, 2004 5:53 pm
Forum: Valveless pulsejet forum
Topic: Nice Curves for a Short Lady?
Replies: 14
Views: 9217

Re: Nice Curves for a Short Lady?

Well I'm very impressed with your work and I believe youv'e provided sufficient evidence,at least as far as Uflow is concerned, to support your findings. This would appear a major development and hope you can put your name to the effect before someone else claims to have observed this previously."Co...
by jmhdx
Wed Sep 01, 2004 7:01 pm
Forum: Valveless pulsejet forum
Topic: Nice Curves for a Short Lady?
Replies: 14
Views: 9217

Re: Nice Curves for a Short Lady?

Not sure what we're seing there Larry but isn't that just the thing with Uflow, unpredictable and unexplainable results can be obtained and I'm sure evidence supporting any theory you'd care to mention could be generated with it. I trust it with simple pipes and simple pressure changes but don't fee...
by jmhdx
Wed Sep 01, 2004 6:22 pm
Forum: Valveless pulsejet forum
Topic: Intake Analysis
Replies: 34
Views: 15335

Re: Intake Analysis

I'm impressed with the efforts made here and wish I could contribute but I have found Uflow chews up hours of time and I'm often unsure of what I'm seeing. Conclusions are difficult to make and wish you luck in finding a rock solid explanation for the double wave through the intake. Uflow was not re...
by jmhdx
Thu Aug 26, 2004 5:16 pm
Forum: Tools and Construction
Topic: Materials
Replies: 16
Views: 7996

Re: Materials

Love that SRB story, feasable if not true. This is the wrong forum for this but I'd like to add why we Brits drive on the wrong side our inherited Roman roads. Napoleon Bonaparte being a big picture kind of guy knew that most men carried their swords or otherwise in their right hands and commanded a...
by jmhdx
Tue Aug 24, 2004 6:39 pm
Forum: Tools and Construction
Topic: Materials
Replies: 16
Views: 7996

Re: Materials

Thanks Jim, they predictably only sell tube of relatively large wall thickness, great for welding but a little to heavy to impress. The light weights possible for pulsejets are one of the key advantages and we have to make the most of them to compensate for the all too obvious disadvantages. An audi...
by jmhdx
Mon Aug 23, 2004 6:57 pm
Forum: Tools and Construction
Topic: Materials
Replies: 16
Views: 7996

Re: Materials

Well thanks, I'm guessing youv'e worked or studied in Oxford to know the directions. It's spelt Kingston Bagpuize but Yell has not yeilded any results for metal stockists. I'll keep trying. I don't suppose you know where I can find a fully equiped workshop with sound proofing and ventilation and per...
by jmhdx
Mon Aug 23, 2004 6:28 pm
Forum: Valved pulsejet forum
Topic: Straight tailpipe length with new(?) valve arrangement...
Replies: 31
Views: 14047

Re: Straight tailpipe length with new(?) valve arrangement..

Hank, I agree with you. I never said a straight duct was for an amateur enthusiast. I just said it can be done with good results with valves and may just be possible without valves. Indeed, in some respects it may well outperform the duct with bulges and constrictions. But, it is certainly a job fo...
by jmhdx
Mon Aug 23, 2004 5:47 pm
Forum: Tools and Construction
Topic: Materials
Replies: 16
Views: 7996

Re: Materials

It's a long and tiresome task to find thin wall stainless tube, I've given it a couple of hours and given up as I need so many other things besides. I've found tube down to 1.5mm wall thickness only and then the minimum order was five three metre lengths. If any usable material is found please let u...
by jmhdx
Wed Aug 11, 2004 7:18 pm
Forum: Valveless pulsejet forum
Topic: Ram Air for a HL?
Replies: 14
Views: 5421

Does a straight lockwood type engine, when travelling fast enough, have almost no output through the intake. I think when ram pressure is high enough all the expanding gases will exit through the rear. Mike Everman amongst others has blown out the flame before. If you want ram air without increases ...
by jmhdx
Wed Aug 11, 2004 6:26 pm
Forum: Valveless pulsejet forum
Topic: BCDSVP idea...
Replies: 13
Views: 8179

Hi mk, glad to see your mind is busy. I hope I have a shortcut for you. Build two identical engines of your proven KPT design and point the intakes at each other(a long length of angle iron would be useful), start them both three feet apart then slowly bring them closer together. I'm imagining if th...
by jmhdx
Tue Aug 03, 2004 8:22 pm
Forum: Valveless pulsejet forum
Topic: The Shape of Things to Run - First Fo Mi Chin Pics
Replies: 16
Views: 8474

I'm impressed, thats a very memorable image, foam can indeed. Is this the first engine we've seen with the "gap" after acceleration?. Obviously reynst and the bcvp have this function but this is a single chamber two pipe motor with gap after acceleration which for my money should stop it getting out...