Calling all sooties

[Barch]

We recently did a graphic for some aircrew training and was told the Nozzle Guide Vanes were the wrong way round, since then another instructor has come on the scene and said that the NGVs are the wrong way round.

So which of these graphics shows the NGVs in the correct orientation?

AdvTHANKSance

 

[ady eflog]

Bottom diagram is correct as the NGV should present the air to the pressure face of the blade.

 

[Barch]

Bottom diagram is correct as the NGV should present the air to the pressure face of the blade.

Cheers

That is the original graphic before being coloured.

 

[Stevienics]

Could be miles out, but I agree. NGV's , as I recall, convert hot gases to kinetic energy to make the whirly things spin around as well as making sure it points in the right direction for maximum impact and to do this, they need to change the direction of the gases.

 

[ady eflog]

View attachment Doc1.doc


its all to do with entry/exit vector drag apparently........

 

[tonkaplonka]

Convergent ducts!! Decrease pressure, increase velocity. You should have a wee read of the Rolls Royce book. The gas turbine bible.
I agree, the bottom diagram is correct.

 

[Barch]

Convergent ducts!! Decrease pressure, increase velocity. You should have a wee read of the Rolls Royce book. The gas turbine bible.
I agree, the bottom diagram is correct.

I lost mine at the end of training in 77.

 

[Throatarea]

Hi,

I agree that the bottom is more correct, however they do not look very convergent to me, so from a schematic point of view it can give the wrong impression.

TH

 

[Barch]

Hi,

I agree that the bottom is more correct, however they do not look very convergent to me, so from a schematic point of view it can give the wrong impression.

TH

The picture is taken from the Aircrew Manual, they spend about 10 seconds on the NGVs so 'it will do a trip'.

 

[matkat]

I also agree the bottom one is the correct one.

 

[art252]

I agree the bottom picture is more correct but I think the angle of the nozzle blades should be rotated 45 degs clockwise to be more effective in directing the gas onto the 1st stage turbine.Then again artistic licence lets you get away with allsorts.
Arthur