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Morgarella [4.7K]

4 years ago

15

Steam enters an adiabatic nozzle at 2.5 MPa and 450oC with a velocity of 55 m/s and exits at 1 MPa and 390 m/s. If the nozzle ha

s an inlet area of 6 cm2, determine (a) the exit temperature.

1 answer:

luda_lava [24]4 years ago

4 0

Answer:

The value of exit temperature from the nozzle = 719.02 K

Explanation:

Temperature at inlet $T_{1}$ = 450°c = 723 K

Velocity at inlet $V_{1}$ = 55 $\frac{m}{sec}$

velocity at outlet $V_{2}$ = 390 $\frac{m}{sec}$

Specific heat at constant pressure for steam $C_{p} = 18723 \frac{J}{kg k}$

Apply steady flow energy equation for the nozzle

$h_{1} + \frac{V_{1} ^{2} }{2} = h_{2} + \frac{V_{2} ^{2} }{2}$

$C_{p} T_{1} + \frac{V_{1} ^{2} }{2} = C_{p} T_{2} + \frac{V_{2} ^{2} }{2}$

Put all the values in the above formula we get,

⇒ 18723 × 723 + $\frac{55^{2} }{2}$ = $C_{p}$ $T_{2}$ + $\frac{390^{2} }{2}$

⇒ $T_{2}$ = 719.02 K

This is the value of exit temperature from the nozzle.

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1) Notation

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