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I hope that, given I've sourced what I can, you may be able to help? I'm Currently working on a lab report for my Aeroengines unit based on Convergent-Divergent nozzle (http://imgur.com/HQML2Au).

From the drawing, I have been provided D1, D2, D3, D4, T1, T2, T3, T4, P1, P2, P3, Velocity, Ambient Pressure and Ambient Temperature.

I need to calculate the following:

- Mass Air Flow rate through the system at each inlet valve.

- Velocity at each section (inlet, throat, exit) of the nozzle.

- Speed of Sound at each section (inlet, throat, exit) of the nozzle.

- Mach No. at each section (inlet, throat, exit) of the nozzle.

I don't have a real grasp of this subject, but from some text-books I've figured out the following, and mainly, I just want to ensure what I'm doing is correct.

•Mass Flow Rate

Density x Surface Area x Velocity Density = pRT, so I assume I'd take P1, and divide by (T1 x Universal Gas Constant)

Surface Area = (Pi x D12)/4

Velocity = Provided as part of the experiment.

Velocity

Continuity Equation = p1A1V1=p2A2V2 Now that I have p1 and A1 from the previous part, I should be able to rearrange to get V1? I'm assuming this would be the same for V3, V4?

Speed of Sound

I have this for a perfect gas: a = ROOT(yGcRT) So Root(specific heat ratio(?) x Newton's Constant x Gas Constant x Temperature?)

Not sure how to calculate each part of this

Mach No. M2 = V2/(specific heat ratio(?) x Newton's Constant x Gas Constant x Temperature?)

Any help at all would be appreciated, I've worked out what I can, as I don't want to flat-out ask for answers...

Thank you! :)