www.pulse-jets.com

I've thought of similar ideas. One idea that springs to mind after seeing your design is rather than having a flexing membrane, have a sliding part, but then you have a moving part and all of its associated problems. Another thing I thought of about ten years ago is to control the firing of the sepa...

The thing that throws me for a loop as an American who frequently listens to the "BEEB" (BBC world service). Is when large mumbers are discussed. For example: US 1x10^6 = Million 1x10^9 = Billion 1x10^12 = Trillion UK 1x10^6 = Million 1x10^9 = Thousand million 1x10^12 = Billion? 1x10^15 = Trillion? ...

That's neat. I think the funnest part of that is draging the shape of the wing and watching the shock/expansion waves and lift/drag vector flit around while you rearange the shape. Cool!

cudabean

Yep! got that book, and a very good book it is too, thanks for the links Bruno I will check them out. Hmm.. I ordered that book from Amazon too! I like it except for the way that pulsejets are summarized in a paragraph or two, IIRC. http://www.iop.org/EJ/abstract/1468-5248/3/1/030 http://www.turbul...

Mike,

Cool looking divergence on the exhaust. Good luck!

cudabean

Why not EDM? Electrical Discharge Machining. Perhaps slightly more trouble than a chemical process because you first need to create a metal electrode. The electrode is simply a negative shaped "die" that you apply electricity to and it slowly eats away the metal material as it sinks through your sta...

There was a discussion on PICs in the off-topic forum a few days ago. I just did a search and it looks like you can cross-compile a PIC program on your PC using gcc (GNU C compiler), which is free and should be runnable in windows using Cygwin. Anyone have any experience (good/bad) with this? cudabean

Nice. Thanks Bruno.

One question. I calculated the area of the exhaust (disregarding wall thickness) as being 387 mm2, but the intake area is 1225 mm2. Would this tend to make the intake be the primary exhaust?

cudabean

Chris, That's nice. I like how you have streamlined it. My only suggestion would be to rearrange the exhaust so that it "hugs" the interior thereby heating the interior air passing through as much as possible, which should also help cool the exhaust and hopefully quiet it down a little. Here's a sli...

What I am after is a low-speed ramjet. An engine that craetes its own ram pressure, at standstill if need be. Hmm, yeah, I think I see what you're saying. Maybe, in the case of a lockwood type, the short lockwood "intake", if it didn't poison the air too much, could double as a pressure generator d...

Why do you think I like the annular configuration so much?

What? They allow super-sonic ultralights in Croatia? What a deal! ;)

cudabean

Didn't want to distract the main SP-14 thread, so I thought I'd start a new thread for this tangential idea. It seems to me that it would not be too difficult to create a ramjet hybrid out of Bruno's SP-14. I guess you would perhaps equip the motor with a central spike for a compressor and allow it ...

Insideout? How about calling it an anular lockwood? One feature I particularly like about it is it seems to have a built in thrust augmentor that admits fresh air and heats it up, then mixes with the exhaust. This would probably help keep the noise down some because all of your high velocity hot gas...

The reason for a continuous taper is that any sudden change of section generates wave reflections. Constant section and constant taper diffuser don't. If your design already generates all the reflections you want, well, then you want to avoid any additional points at which a reflection can occur. S...

One thing that I've noticed about Lockwoods is the main exhaust is a continuous taper from the exhaust to combustion chamber. What's that about anyway? Mike, do you plan to implement that in the Kazoo? If so, will you be able to control the squish so that your cross sectional area diminishes as it g...