Can't seem to figer this Gas turbine calculation please help?

Question

Inlet Temp=277.5K
Temp rise in combustor=445K
Compression ratio= 4:1
exhaust gas velocity= 143m/s
Gamma=1.4 Cp=1.005 and Cv=.718
I can find temps and pressures at all stages but need to know the net power produced and can't figure how to use the 143 m/s

Answer 1

Have you tried putting your data into the conservation of energy law by Bernoulli. If you have the Pressures at all stages:

Energy In = Energy Out
which is re-wriiten:
Total Pressure In = Total Pressure Out
P + 0.5*rho*v^2 = P + 0.5*rho*v^2
In Out
(You can ignore hydrostatic pressure differences)

Look it up.

But it sounds as though you have done most of the work.

The Power in the gas stream is:
P = 0.5mv^2 where m is the mass per unit time.

or you may need to use the Impulse Equation:
F.t = change of momentum
F = change of momentum / time

using the rate of momentum production of the hot gas.


These are just a few ideas that could be completely off beam; but email me if you need a bit more steering.

RCat