Search found 63 matches

by serverlan
Wed Jul 01, 2009 9:19 am
Forum: Valveless pulsejet forum
Topic: Few Quick Questions...
Replies: 79
Views: 5752

Re: Few Quick Questions...

Hi all, I pose the quation about "why does the gas burn at the end of the tube" a while back also [url]http://www.pulse-jets.com/phpbb3/viewtopic.php?f=3&t=5240&p=62323#p62323[url] I just thought I'd have a go at summarising what I have thnuked out since then. A bunsen burn is a device that mixes fu...
by serverlan
Sun Jun 14, 2009 1:52 am
Forum: Valveless pulsejet forum
Topic: Real VPJ stats
Replies: 4
Views: 804

Re: Real VPJ stats

Hi Eric, I actually start with a notional full fuel/air charge in uflow, run the simulation for one cycle, and dump its data to calculate the next fuel/air charge volume. This gives me a percentage for the charge for the next cycle. I put that in, runce the sim, export the data and calculate the cor...
by serverlan
Sat Jun 13, 2009 12:20 pm
Forum: Valveless pulsejet forum
Topic: Real VPJ stats
Replies: 4
Views: 804

Re: Real VPJ stats

Just to wrap this up, the engines are definitely running at kadency frequencies, not resonance frequencies The simulations show what is probably a 10:1 difference betweent he two. The resonance occurs at much higher frequencies. The timing of the "real" jets seems to be determined by the ratio of co...
by serverlan
Fri May 22, 2009 4:58 am
Forum: Valveless pulsejet forum
Topic: Real VPJ stats
Replies: 4
Views: 804

Real VPJ stats

Hi all, I'm not a builder, but dable in the theory. As such, Uflow1d has been invaluable, I am getting to the stage where I think I can ask it meaningful quastions and get vaguely meaningful results. What I would like, is the dimesions of a real pulsejet someone has buld, and its resonant frequency....
by serverlan
Fri May 22, 2009 3:57 am
Forum: Valveless pulsejet forum
Topic: Lockwood simulations, wow
Replies: 22
Views: 2295

Re: Lockwood simulations, wow

What's the software used?
by serverlan
Tue May 19, 2009 2:16 am
Forum: Valveless pulsejet forum
Topic: Lockwood simulations, wow
Replies: 22
Views: 2295

Re: Lockwood simulations, wow

Some of the prettiest bowel simulations I've seen.
by serverlan
Mon May 18, 2009 7:00 am
Forum: Valveless pulsejet forum
Topic: Lockwood simulations, wow
Replies: 22
Views: 2295

Re: Lockwood simulations, wow

Lockwood simuylations

I can't see much pulsing, and the time scale goes up to 10 seconds or so.

"me no unnerstand"

Don
by serverlan
Mon May 18, 2009 6:47 am
Forum: Valveless pulsejet forum
Topic: Engineers do VPJ
Replies: 2
Views: 632

Re: Engineers do VPJ

Heres another one (one pager)
that sounds like it might be useful, but on my limits of understanding.

I think they are implying that a triangular inlet may be better for a pulsejet than a circular one?

http://www.mecheng.adelaide.edu.au/~pvl ... stract.pdf
by serverlan
Wed Apr 29, 2009 1:06 pm
Forum: Valveless pulsejet forum
Topic: Engineers do VPJ
Replies: 2
Views: 632

Engineers do VPJ

http://www.mecheng.adelaide.edu.au/~marjom01/Honours%20projects/2008%20honours%20projects/The%20Design%20and%20build%20of%20a%20pulsejet%20UAV_files/Final%20Report.pdf A bunch of engineers try to build a valveless pulsejet UAD for their Masters. They work on a chinese and a FWE. References to Larry...
by serverlan
Tue Apr 21, 2009 5:36 am
Forum: Valveless pulsejet forum
Topic: Flame Question
Replies: 2
Views: 613

Re: Flame Question

Here is a conversation i'/ had with someone building forges and the like using LPG burners Hi Tim, I was searching on the internet to find an explanation of the following "why does the flame tend to sit at the end of a burner, rather than moving back up the tube (back-burning)" I found your article ...
by serverlan
Sun Apr 19, 2009 8:55 am
Forum: Valveless pulsejet forum
Topic: What would happen if...
Replies: 9
Views: 815

Re: What would happen if...

Sorry, but anything space-going uses hydrogen oxygen mix as a rocket - e.g. Saturn 5, Shuttle, etc.
by serverlan
Sun Apr 19, 2009 1:01 am
Forum: Valveless pulsejet forum
Topic: What would happen if...
Replies: 9
Views: 815

Re: What would happen if...

You wouldn't need an air intake then, so the entire engine design would change to become a rocket, rather than a jet.
by serverlan
Sun Apr 19, 2009 12:59 am
Forum: Valveless pulsejet forum
Topic: What would happen if...
Replies: 9
Views: 815

Re: What would happen if...

Try injecting some water as well internally. The heat should turn it to steam
improving the volumetric change and cooling the engine a little.

Look up "chemical intercooling" in rev-head space.
They injecta mix of methanol and water.
by serverlan
Sat Apr 18, 2009 2:11 pm
Forum: Valveless pulsejet forum
Topic: What would happen if...
Replies: 9
Views: 815

Re: What would happen if...

You could try using Nitrous Oxide in stead of straight O2
Standard rev-head technology
by serverlan
Sat Apr 18, 2009 1:57 pm
Forum: Valveless pulsejet forum
Topic: Flame Question
Replies: 2
Views: 613

Flame Question

Can someone explain the way flames sit at the end of tubes, even though the fuel and air are mixed long before in the the tube? Some examples - The bunsen burner. Air and gas are introduced at the bottom, but never burn until they reach free air at the top. I have a gas needle-yet, which sucks the a...