And I was wondering if yesterday's light activity was because I finally exposed my colossal and insurmountable ignorance! I woke up at 5am (I think because I heard Bruno shouting half a world away) after an evening of messing with the original layout, see below. I'll take the comments in turn:
bruno wrote:the best aspiration you can find is achieved in the Logan pulsejet, which has a side intake at about the middle of the chamber.
I had seen a reference to this in mining the old forum, and that is one reason I moved to tubes. (BTW: any more info on the NRL?)
bruno wrote:... what heating of the charge? How much do you think charge can get heated from a few inches of duct wall?
Finer point of the design, to be sure, but the original configuration has two 90deg turns with one wall being the CC; how much can it heat the charge? Don't know, but this is different from straight pipes and I imagine quite a bit of shear derived turbulence through the turns, allowing more heat transfer than normal. As cool or as cooled as they can get will have benefits, I think, like an intercooler on piston engines. Again, a plus for tubular intakes with some space and cool flow between them and the CC.
viv wrote:The four tubes on the Kentfield engine are mounted on a simple circular plate, if you put your front end on to this plate you can test and modify the engine with ease.
Where is that old Kentfield I had in the attic? LOL Perhaps if we could get Bill Hinote to chime in, I could make a head for his motor. He lives only a two hour drive from here, I believe...
viv wrote:I prefure the 8 tube layout even though Bruno correctly point out that it is introducing a new varible.
Sure is less parts to go with 4, and still interleaved, still the same potential benefits, maybe less augmentor turbulence? The more the better for intake cooling, but as Bruno says, this is probably polishing a turd.
Finally, now that some proportions are taking shape, my current efforts in the design are focusing on what I think I can make easily.
1. My welder is only good for carbon steel, so tha's what I'll experiment with
2. I have a small press, and think I can make either the sheet intakes or form the tube types in halves from sheet, from dies I can also make. Everything else is shear, bend and weld.
The finer points of experimentation are going to be aspiration, fuel flow, ignition among others. I'd be happy to send part sets to anyone that wants to build concurrently with me.
The material cost is nil, it's all labor, so who wants to get a package in the mail? We can do something really cool here.
I can't say the first hardware will be completely designed by committee, but I've grown to value greatly the input from you all, and I also know myself, I will only experiment so far after building the basic setup, even or especially if it works! I am a manufacturer with pretty good resources and I think that we, as a team, could eventually offer an extremely cool kit, and dedicate the proceeds to (our collective) R&D!