Question

Consider an adiabatic throttling valve with water entering at pressure of 1.5 MPa, a temperature of 150°C and a velocity of 4.5 m/s. Determine the velocity at the exit.

Answer 1

Answer:

So the exit velocity of water is 4.5 m/s

Explanation:

Given that

Water entering pressure = 1.5 MPa

Temperature = 150°C

Velocity = 4.5 m/s

From first law of thermodynamics for open system

$h_1+\dfrac{V_1^2}{2}+Q=h_2+\dfrac{V_2^2}{2}+W$

Here given that valve is adiabatic so Q= 0

In valve W= 0

Wen also also know that throttling process is an constant enthaply process so

$h_1=h_2$

$h_1+\dfrac{V_1^2}{2}+Q=h_2+\dfrac{V_2^2}{2}+W$

$h_1+\dfrac{V_1^2}{2}+0=h_1+\dfrac{V_2^2}{2}+0$

So from above equation we can say that

$V_2=V_1$

So the exit velocity of water is 4.5 m/s