Can the OF people here give some guidance on the possibility of integrating trees/tree canopy in the cfd simulations via butterfly (A separate component in next release would be awesome!!!)
I had the impression that simple geometries (boxes) representing the trees/canopy which can strip off momentum or act as a sink along with creating the necessary turbulence would do the job. After reading some stuff I realized there are a lot of factors like leaf area density/index, drag coefficients, turbulent kinetic energy/dissipation, etc. (one of the reference)
Can someone shed some light on how can a momentum equation be integrated via butterfly…if possible. As I stated earlier, a separate component with inputs for all necessary parameters to model tree canopies would be great!!
Similarly, modelling louvers via butterfly would be another interesting topic of discussion.
Thanks a lot for the quick reply @TheodorosGalanos. Good to know the team has this topic into consideration and is in active development. In the meantime I will read about porousSimpleFoam and the % reduction of momentum for one or two typical tropical species.
I’ll be honest I have no clue lol. I tried back then to find things about these but it seemed so obscure. In general there is no easy way to calculate these for a tree canopy and then every canopy is different.
An approach I ended up using is a simple box model with a static velocity inlet and a ‘tree’ box region inside it. I then went ahead and tried different coefficients until it got me the % of reduction I expected or wanted.
That said, for artificial constructions that can actually be modelled and meshed, there is a way to calculate the viscous and inertial coefficients by sampling at many different locations before and after the geometry, calculating pressure drop, and fitting a 2nd order polynomial to those. The coeffiecients of the polynomial are the coefficients you use after that.
I have an excel file somewhere for all that, I’ll try to find it.
Hi, @TheodorosGalanos I had used the BF for modelling outdoor air movement. It is working very well and promising. Currently, I wish to add trees into the model as porousSimpleFoam, the joke is that I could not find any method to do in BF. I request for your help. Thanks