Flow Through a Pipe: Modelica Model with Unequal Inlet-Outlet Areas

[polezero]

Hello guys,

I need to model a pipe in modelica. Now modelica has its own fluid library where i can find a model of a pipe. But i need to model a pipe which has unequal inlet and outlet area. The outlet of the pipe is smaller than the inlet. Since mass going in the pipe=mass going out, hence the velocity of the fluid at the outlet should increase. I need a detail mathematical expression of this behavior. Please help me out.

 

[minger]

http://www.google.com/search?source=ig&hl=en&rlz=&=&q=pipe+flow&aq=f&aqi=g10&oq=

You might want to be a little more descriptive.

 

[FredGarvin]

Bernoulli with loss terms included for frictional/viscous effects? Seems pretty cut and dry.

 

[rythreion]

you can ask for a help in http://waterdesign.tk/ you ask them about pipes. they can help you

 

[alphy]

Hello there,

Thank you for reaching out regarding your modelica project. Modeling a pipe with unequal inlet and outlet areas can be a complex task, but it is certainly possible with the right approach.

Firstly, it is important to understand the fundamental principles of fluid dynamics and how they apply to pipes. As you mentioned, the mass flow rate through the pipe must remain constant, meaning that the velocity of the fluid must increase as it passes through the smaller outlet area. This is known as the continuity equation, which states that the product of the cross-sectional area and the velocity of the fluid must remain constant along the length of the pipe.

To model this behavior in modelica, you will need to use the appropriate equations and parameters from the fluid library. You can start by defining the inlet and outlet areas of the pipe, as well as the fluid properties such as density and viscosity. Then, you can use the continuity equation to calculate the velocity at the outlet based on the known values at the inlet.

It may also be helpful to consider the Bernoulli's equation, which describes the relationship between the pressure, velocity, and elevation of a fluid in a pipe. This can provide additional insights into the behavior of the fluid as it passes through the unequal areas.

Overall, I recommend consulting with a fluid dynamics expert or referring to textbooks and other resources on fluid mechanics to ensure that your model accurately represents the behavior of the pipe. I wish you the best of luck with your project and hope this information helps you in your modeling efforts.

Best regards,