Solving Basic Thermo Questions: Calculating Velocity and Area in an Open System

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rjenkins
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I have question (probably figured that). I have an open system with mass flow rate going into one inlet and going through two outlets. I have all the terms for the two outlets (mass flow, velocity, area, temp, pressure). However for the inlet I'm missing the Velocity and Area.

In solving for the Velocity I figured I could you use the following equation

0 = h1 – h2 + (V1^2– V2^2)/2

But being I have two outlets in this case can I just plug in a 3rd term?

0 = h1 – h2 – h3 + (V1^2– V2^2 – V3^2)/3
 

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So for the inlet velocity I get:V3^2 = 3(h1 – h2 – h3) + (V1^2– V2^2) And then for the area:A3 = M3/(V3*ρ3) Where M3 is the mass flow rate of the inlet and ρ3 is the density of the inlet. Is this the correct approach? Yes, this is the correct approach. To calculate the velocity of the inlet, you can use the equation given above. And for the area, you can use the equation you provided.