Need help with Ramjet design simulation...

[Ranchoth]

OK, here's the situation.

I know a fellow who's the author of a flight simulator program. A good one, too. VERY accurate. Now, he'd like to be able to add true Ramjet/Scramjet engine simulation to the program.

The trouble is, he needs data—detailed data on ramjet operation, and the equations and formulas necessary to accurately simulate different models of ramjets in a flight-sim environment. He mentioned specifically needing info on "thrust and SFC [Specific Fuel Consumption] as a function of mach number."

Sadly, I'm not an aeronautical engineer. Or that good at math. The most I've been able to dig up was this paper on ramjet design from 1954, and it apparently didn't have the information that my friend needed. But surely the data is out there, somewhere...the Ramjet was invented in 1913, after all.

Well...can anyone help? I'd owe you one.


Ranchoth

[Tuckerfan]

Have you tried checking with the folks at Arnold Air Force base? They, along with NASA have been doing a lot of work on scramjets of late, and while they might not be able to discuss all the details with your friend, they'd certainly be able to help point you in the right direction.

[Jurph]

The AIAA would be a good place to start. They have an annual (?) symposium on air-breathing engines, and since regular jet engines are at the point where most of the breakthroughs are really just refinements, the "sexy" papers presented usually involve more exotic forms of propulsion: ramjets, scramjets, and pulse jets. He should be able to borrow the abstracts of the annual symposium at any university's engineering library, and from there, contact the professors who are doing the work.

Unfortunately, wind tunnels aren't free. Most wind tunnel data is bought very dearly by the hour, and so your friend may find that many of the owners of the data are reluctant to give it away. On the other hand, he may find that because it is infinitely shareable and so precious, that it is very simple to get his hands on.

Other groups who might be willing to help include JANNAF, the CPIA, and the JPL.

[Wikkit]

There's a ramjet simulator here, you could harvest data from it or e-mail the author for the underlying equations. Scramjet information will be much more difficult, if not completely impossible, to come by.

The other problem is that you can't take off with a ramjet or scramjet, so using it in a flight simulator would be difficult.

[Ranchoth]

Originally Posted by Wikkit

The other problem is that you can't take off with a ramjet or scramjet, so using it in a flight simulator would be difficult.

Difficult perhaps, but not impossible. The simulator already supports JATOs, and using more than one type of engine on a single aircraft. It shouldn't be than big a deal to get the simulated aircraft up to the right speed to get the ramjet working.