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

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The discussion focuses on calculating the inlet velocity and area in an open system with multiple outlets. The user correctly applies the energy conservation equation, modifying it to account for three terms: h1, h2, and h3, leading to the equation 0 = h1 – h2 – h3 + (V1^2– V2^2 – V3^2)/3. This approach allows for the determination of the inlet velocity (V3) and area (A3) using the mass flow rate (M3) and density (ρ3) of the inlet. The provided equations are confirmed as accurate for solving the problem.

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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.
 

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