Update + Happy Yalda!

Tonight is the longest night of the year (in the northern hemisphere of course) and a good excuse to send a loong post to update you about Ladybug + Honeybee + Butterfly and celebrate the loooong night. So here we go!

1. Honeybee is brown and not yellow [stupid!]…

As you probably remember Honeybee logo was initially yellow because of my ignorance about Honeybees. With the help of our Honeybee expert, Michalina, now the color is corrected. I promised her to update everyone about this. Below are photos of her working on the honeybee logo and the results of her study.

If you think I’m exaggerating by calling her a honeybee expert you better watch this video:

Thank you Michalina for the great work! :). I corrected the colors. No yellow anymore. The only yellow arrows represent sun rays and not the honeybee!

2. Yellow or brown, W[here]TH Honeybee is?

I know. It has been a long time after I posted the initial video and it is not fun at all to wait for a long time. Here is the good news. If you are following the Facebook page you probably now that the Daylighting components are almost ready.

Couple of friends from Grasshopper community and RADIANCE community has been helping me with testing/debugging the components. I still think/hope to release the daylighting components at some point in January before Ladybug gets one year old.

There have been multiple changes. I finally feel that the current version of Honeybee is simple enough for non-expert users to start running initial studies and flexible enough for advanced users to run advanced studies. I will post a video soon and walk you through different components.

I think I still need more time to modify the energy simulation components so they are not going to be part of the next release. Unfortunately, there are so many ways to set up and run a wrong energy simulation and I really don’t want to add one new GIGO app to the world of simulation. We already have enough of that. Moreover I’m still not quite happy with the workflow. Please bear with me for few more months and then we can all celebrate!

I recently tested the idea of connecting Grasshopper to OpenStudio by using OpenStudio API successfully. If nothing else, I really want to release the EnergyPlus components so I can concentrate on Grasshopper > OpenStudio development which I personally think is the best approach.

3. What about wind analysis?

I have been asked multiple times that if Ladybug will have a component for wind study. The short answer is YES! I have been working with EFRI-PULSE project during the last year to develop a free and open source web-based CFD simulation platform for outdoor analysis.

We had a very good progress so far and our rockstar Stefan recently presented the results of the work at the American Physical Society’s 66th annual DFD meeting and the results looks pretty convincing in comparison to measured data. Here is an image from the presentation. All the credits go to Stefan Gracik and EFRI-PULSE project.

The project will go live at some point next year and after that I will release the Butterfly which will let you prepare the model for the CFD simulation and send it to EFRI-PULSE project. I haven’t tried to run the simulations locally yet but I’m considering that as a further development. Here is how the component and the logo looks like right now.

4. Teaching resources

It has been almost 11 months from the first public release of Ladybug. I know that I didn’t do a good job in providing enough tutorials/teaching materials and I know that I won’t be able to put something comprehensive together soon.

Fortunately, ladybug has been flying in multiple schools during the last year. Several design, engineering and consultant firms are using it and it has been thought in several workshops. As I checked with multiple of you, almost everyone told me that they will be happy to share their teaching materials; hence I started the teaching resources page. Please share your materials on the page. They can be in any format and any language. Thanks in advance!

I hope you enjoyed/are enjoying/will enjoy the longest night of the year. Happy Yalda!



This is wonderful Mostapha!

That part one Michalina was so cute.
And I just can’t wait to test the new CFD feature!

Happy Yaldā to you too!

Wow :slight_smile:
I enjoyed it
it’s going to be awesome :slight_smile:
CFD component… great feature!!
I’ll be waiting for more videos and component…thanks
Happy Yalda!

Cangrats for all this amazing job , I can only imagine all the hard work that must go into creating this and props to Michalina for tracking down errors and fix them !!

what is she doing? Marking the queen?

hi mostapha! really great work! i have been wating for a plug-in like this!

I want to ask one thing that in my office where I did my training for 6 months they used ecotect for cfd analysis and it gives us very bad data’s… if we compare ecotect with it, will it give better results than that? ecotect’s results are not accurate and its latest release was in 2011.


I asked and here is the reply: “she is marking the drones - male honeybees. The first step to get used to the process before moving to queens!”

Hi Kartik, OpenFoam is a validated CFD engine and as far as you provide the right boundary condition and the right meshing it should provide accurate results. -Mostapha

Thank you all for the kind words! Few more steps to go for the first release of the 'bee. :slight_smile:

thankyou mostapha! I have one doubt till when you will “air” this plug-in for grasshopper!

Hi Mostapha,

My office has been showing increasing interest in running CFD analysis with parametric design in Grasshopper.

Do you have any updates on when Butterfly and etc. will be released? Do you perhaps have Beta version available?

Hi Orn, Kartik, et al.

First of all I’m really so sorry for the delay. As you can read up there release of Butterfly is up to the release of EFRI-PULSE project! I am as frustrated as everybody else not seeing it out yet. I even set-up a call between some of the interested users and EFRI-PULSE project team members, few months ago, hoping that will make the process to go faster but it didn’t seem to make a huge difference.

Unfortunately I have no control on the release date and based on the last call that we had last week it won’t be released soon! :expressionless:

My apologies,


Hi all,

just found this topic and I got very excited, has anything happened in terms of CFD/Butterfly since?

Thank you!


Hi Zita, Not that much really. EFRI-PULSE project never released their code. We are just starting the project again: https://github.com/mostaphaRoudsari/Butterfly

Awesome thanks Mostapha! Still flat out settling into Switzerland but looking to hop back on board sooon!!

Thank you, it sounds great and looking forward to it very much!

Thank you Mostapha, it’s brilliant.

CFD is useful in many ways, even fun!



This is a very old discussion but since a number of people have asked we eventually have a prototype that’s ready for testing. It’s pretty unstable in terms of running iterative studies but works fine for setting up the model and meshing. If you’re an experienced OpenFOAM user who is willing to test the components please get in touch. If you haven’t used OpenFOAM before then wait a couple of more weeks until we have it stable and ready to use by public. Thanks!

Hi mostapha.

Which kinds of CFD modellings are included in this version?

I’m looking for a means of modelling vertical temperature distributions in large atria.
My idea was to cheat, using simple Honeybee tools (vertically dividing the big zone into sub-zones with ‘air walls’), but the ‘air wall’ feature does not seem to allow direct solar radiation and air flow, thus this work-around does not seem to do the job. So it seems I have to go on to CFD modelling.

Can this tool comprehent heat flows - maybe translated into wind speeds due to this flow - or does it only model urban wind flows?


  • Hamborg

Mostapha, this is fantastic! I had OpenFOAM running in Ubuntu before but it has been some time. now I have a more powerful computer so I installed OpenFOAM for Windows. Both the indoor and outdoor simulations are working, visualized in GH. I am a sailor and hydrofoil designer so ultimately want to get to free surface effect simulations. I would not say I am so experienced because I am starting over with OpenFOAM after a few years break, but I have accomplished simulations using Rhino models before, dual booting Windows and Ubuntu, and have all of it working in Windows 10 now. I’m having trouble opening these results in ParaView. I’m not sure if that means much, so far I get similar errors opening the work I copied from Ubuntu to Windows…