Learning Forum

[konstantinospolychronakis10]

Hi everyone, I am trying to model a floating solar pv (with base) in fluent by using the volume of fluid method with the open channel flow model also activated. I also activated the energy equation, the radiation equation and a k- omega turbulence model. My BCs are velocity-inlet and pressure outlet. My fluid domain is an octogon with a total length of 25m. My mesh i believe it is fine based on that i dont have skewness over 0.8, aspect ratio over 12, and orthogonal quality under 0.2. In the manual's reccomendations about open channel flow it says that: "In the case of reverse flow, the pressure outlet boundary behaves as a pressure inlet, and the boundary specific static pressure is taken as the Total Pressure. In this case, the static pressure is calculated from the total pressure.You can use the following text command to fix the boundary-specified static pressure, which helps to suppress reflections from the pressure boundary for certain cases: solve → set → open-channelcontrols". The problem that i am facing is that i still have reversed flow and the variables that are not converging are continuity k and omega.

 

I have also tryied the following:

1) denser grid 

2) face meshing in pressure outlets

3) relaxation factors

Do anyone has any idea on how can i solve this problem?

[SRP]

Hi,

Reversed flow at the pressure outlet may indicate that the outlet is too close to flow recirculation or disturbances. If possible, extend the length of the domain downstream of the PV system to allow flow to stabilize before reaching the outlet.