## Fluids

Topics relate to Fluent, CFX, Turbogrid and more

#### How to plot concentration of a mixture in Fluent

• DivyajyotiBasu
Subscriber

Hi, I'm currently doing a simulation where I need to analyze the properties of a water-ethanol mixture in closed a cavity with given boundary conditions.

For the cavity I have taken a 2-D surface geometry and set it to fluid. I'm confused as which solver model I should use. Also it would be helpful if anyone can tell me how to plot the concentration of the mixture after the calculations are done as I need to determine the concentration at the mid-section of the cavity. Thanks in advance.

• DrAmine
Ansys Employee
Species model should be used. Please go through some tutorials.
• DivyajyotiBasu
Subscriber

Thanks form your response. I have run a simulation using the species transport model. But now when I'm trying to plot the volume fraction of respective phases in XY Plot its showing some discrepancy, like I'm using a 5X5 cm square 2-D geometry as my cavity but when I'm setting the X plot direction to 0.05( default Ansys units are in m) the graph is showing X upto 0.0025m, also the graph is coming dispersed instead of a curve. I need to find the concentrations at the mid line of the cavity.

• Rob
Ansys Employee

Have you created a line (or rake) body and plotted on that?

• DivyajyotiBasu
Subscriber

I'm sorry but I didn't get your question as I'm actually new to fluent. I've first created a 5X5 cm square in Design Modeler then I created a surface using that sketch and set it to fluid.I turned on Mesh and created a refined mesh using the geometry, I've  named the edges as left, right, base and top respectively. Then I switched to Ansys setup and selected gravity in the -y direction and used a multiphase mixture with water as primary phase and ethanol as secondary, and selected energy equations, viscous laminar, species transport with thermal diffusion. As boundary conditions I've put the left edge at 300K and right edge at 318K.

I initialized the setup and started calculations from the right edge for 1e5 interations and now I'm facing problems while finding the concentrations at the mid-line.

• DrAmine
Ansys Employee
Carry out some tutorials. If still not clear get back to us.