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Jet Engine Model Library for Orbiter 2016 2

I've updated the add-on download to include the project code for the Jet Engine Library. I am on a Linux box now and can't easily develop Orbiter modules anymore, so I decided to put this out there with the hope that someone might want to pick it up and run with it. The original add-on module has not been changed.

If you have a question about what I did in this code, feel free to PM through OF. I don't have any particular licensing restrictions other than I don't expect you to blame me if you do something stupid with the code, or whine at me that it doesn't have feature X that you sorely want. Some attribution in your code would be nice, if for no other reason it will help direct users to me to ask questions about the code. If a code guru wants to pick this up I'm happy to help with the thermodynamics (I am an engineering professor and teach thermodynamics as my day job).

There are certain deficiencies that I know exist, which are somewhat by design as this is a complex model and certain linearizations were needed to get this to work at all. A major one is the determination of the air density at the inlet, which is needed to determine the mass flow rate of air through the engine and the pressure at the compressor inlet. Right now it assumes an isentropic deceleration/compression of the airflow, which is fine for flight Mach numbers less than one, but is incorrect for supersonic flight where shocks will form upstream or inside of the intake. Jets with the capability to cruise at supersonic conditions (e.g. Concorde, B-70, etc..) achieve most of their compression not in the compressor, but in the intake, something like a ramjet. The current model does not accurately capture this effect. There are ways to model these effects but they are dependent on the intake geometry.


Thunder Chicken
There were a couple of mislocated lines of code in the main library that needed to be in the header file. This would cause a compilation error for missing Isp definitions.

An updated version with this correction has been uploaded.