Centerline Compression Turbine Engine

[bluewater68]

I am interested in the fluid dynamics of a turbine engine that compresses its exhaust gasses along its centerline.

http://www.faqs.org/patents/app/20090067983

Any thoughts?

 

[minger]

Well the patent doesn't mention any compressor section. Having claimed that the inlet and combustion section are essentially the same, I'd be interested to see how efficient the combustion can be at what would be near atmospheric pressure.

Other than that, I don't see the device working very well anyways. Just a gut feeling.

 

[FredGarvin]

Oh boy. There are a lot of red flags going up on this one. The biggest being what minger pointed out. The burner being in the inlet? How are you going to get any flow by putting a slight blockage in the front of the engine? The combustion will be terrible. It will be very low flow unless it has a forced forward velocity like a ram jet needs.

The mechanical make up is very suspicious too. This sounds like it would need turning angles in the "turbine" section of darned near 90°. The aerodynamicists will not like that one bit. The there is the issue of bearings. How are these rings going to be mounted?

I'll stop here for now. Better hurry up and apply for that patent before putting any real thought into how things should work.

 

[bluewater68]

Thanks for both your replies.
I won’t pretend that I have all the answers and there are obvious bugs that would need to be worked out.
The combustor is in the intake, Figure 3.
Thrust is directed toward the rear of the engine and the only way for it to come out the intake is for its energy to be expended against the turbine blades.
The turbine blades are held in place inside a ring, Figure 2.
Each blades angle of attack would vary depending on if it is from the center to the outer ring and probably on its position along the length of the engine.
I had mentioned magnetic barring, but conventional barrings could be held in place on the ring or the casing.

Thanks again for both your interest.
William

 

[FredGarvin]

Let's start with the most basic questions I can think of:

What will initiate flow into the "turbine?" The way I see it, right now, there is absolutely nothing. Just because you squirt fuel into a burner and even burn it, does not mean you are going to induce a flow. In other words, you have this thing sitting on a tarmac at sea level static conditions. How does it start?

Next question:
What will be the the reason that the airstream will accelerate and thus, produce thrust? There is no thrust producing aspect to this concept.

Third question:
You call this a "center line compression turbine." What component actually compresses the air stream?

To me it looks like you are trying to run a Brayton cycle but with the first part of it missing.

I won't even start on the real design aspects that are not going to work either.

 

[bluewater68]

Most likely, airflow will be initiated from a turbocharger, then bled from the engine.
The combustor is basically a rocket engine thus producing thrust above the speed of sound.
The exhaust gasses from the combustor act upon the turbine blades causing each ring to spin.
The curve of each turbine blade forces air towards the centerline and back through the engine.
And no, it is not the Bryant cycle as there is no shaft and the compressor and turbine blades are one and the same.

 

[FredGarvin]

Most likely, airflow will be initiated from a turbocharger, then bled from the engine.

I don't quite understand that, but OK. I think I can see what you are thinking.

The combustor is basically a rocket engine thus producing thrust above the speed of sound.

What will you use as propellants? Your combustor is actually a combustion chamber? So this would be a rocket, not an air breathing device? Then there is no need for the turbocharger or an inlet for that matter. You will also need a converging-diverging nozzle in there somewhere to get gas velocities above M1.

The exhaust gasses from the combustor act upon the turbine blades causing each ring to spin.

This is similar to what a gas generator would do.

The curve of each turbine blade forces air towards the centerline and back through the engine. And no, it is not the Bryant cycle as there is no shaft and the compressor and turbine blades are one and the same.

You do realize that a compressor and a turbine are polar opposites in terms of what they do. Right? Saying they are one in the same does not make any sense. It's like saying paint and paint stripper are one in the same.

The point I was making about the Brayton cycle is that it appears that you have an incomplete cycle in your idea. It can not be self sustaining.

 

[bluewater68]

If you look again at the image "TurbineRing" you can see that if the exhaust from the combustor would strike the front of the blades toward the center of the ring spinning each ring.

As the rings spin, the back side of the blades compresses air towards the center and back through the engine.

Once the rings are spinning, it is only a matter of diverting some of the airflow to the combustor.