SFEE + Air Question (REPLY SOON PLEASE)

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In summary, the conversation discusses applying the steady flow energy equation and isentropic relationship to find the temperature T2 in a compressor. After simplifying the equation and taking into account the given information, the answer is found to be 5229.3 degrees C.
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Koenigsegg17
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Homework Statement



See attachment please (Note: a lot of extra information is given, all of the information given for the compressor is possibly redundant).

Homework Equations



1) SFEE (steady flow energy equation): q + W = (h2 - h1) + c2^2 - c1^1/2000 + g(z2 - z1)/1000

2) Isentropic relationship: T2/T1 = (p2/p1)^(y-1/y).. (where y = gamma = 1.4)

The Attempt at a Solution



Apply the SFEE to find T2, but how?

I have tried the following:

q + W = (h2 - h1) + c2^2 - c1^1/2000 + g(z2 - z1)/1000.. where W = 0 (no shaft used), c2^2 - c1^1/2000 = 0 (no velocity information provided) and g(z2 - z1)/1000 = 0 (no change in height).

Therefore: q = (h2 - h1)
q = cp (T2 - T1).. where cp = 1.01kg/K, and cp (T2 - T1) is (h2 - h1) for an isobaric process.

Multiplying both sides of the equation by mass flow rate (so that the power given (i.e. heat) can be used in the equation).
q x m = heat energy [kW].

I get an answer of 5229.3 degrees C. (convert units to Kelvins during calculations).Thanks in advance.
Koen.
 

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Never mind. I got my answer.
 

FAQ: SFEE + Air Question (REPLY SOON PLEASE)

What is SFEE?

SFEE stands for Specific Fuel Energy Expenditure. It is a measure of how much energy is required to produce a specific amount of thrust in an aircraft.

How is SFEE calculated?

SFEE is calculated by dividing the fuel consumption rate by the thrust produced. It is typically measured in pounds of fuel per pound of thrust.

Why is SFEE important in aviation?

SFEE is important because it can help determine the efficiency of an aircraft's engines. A lower SFEE indicates that the aircraft is more fuel-efficient, which can result in cost savings for airlines and reduced emissions.

How does air density affect SFEE?

Air density plays a significant role in SFEE. Lower air density means there is less air available for the engine to produce thrust, resulting in a higher SFEE. Conversely, higher air density means more air is available, resulting in a lower SFEE.

What factors can affect SFEE besides air density?

Other factors that can affect SFEE include the type and condition of the aircraft's engines, the weight of the aircraft, and the altitude and speed at which the aircraft is flying. These factors can all impact the efficiency of the engines and, therefore, the SFEE.

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