Simulation using PCM and NoMass materials

grasshopper honeybee
1

Hello helpful communities!

I need to confirm is my work correct or not.
I want to simulate a hypothetical room which have 2 scenario.
First, the wall consist of several layers, such as Plywood, Alumunium Foil, and PCM. PCM is in the middle of the wall, where alumunium covered it all before plywood covered and become the outer side of the wall
Second, the wall only consist of two layer plywood, where there are no materials between the plywoods.
Here I attached the visualisation of the hypothetical rooms

2 options materials
2 options materials731Ă—684 42.3 KB

And please take a look to my script
Surface Temperature_With PCM.gh (252.0 KB)
Surface Temperature_Without PCM.gh (241.1 KB)

I already read a forum discussed PCM in their wall, however, it was 7 years ago and they use Legacy and “additional strings”. I haven’t deep dive into it and decided to change the conductivity, density and specific heat to represent the PCM materials. I don’t know is it enough?

I already conducted the simulation, however, the simulation results is not similar with measurement result, where surface temperature of the wall with PCM is smaller than the wall without PCM. I guess there is something wrong, but I still haven’t figure it out yet.

To conclude, my questions are
(1) Is it true to apply PCM in our walls, we have to settings the additional strings?
(2) Is there something wrong with my script? Currently I am not using any additional strings settings for applying PCM

Thank you in advance!

2

Hi, can anyone assist me for this case? I appreciate for any response :pray: thank you @chris @AbrahamYezioro

3

Hi. Could you complete your simulation using PCM?

4

I completed my simulation using PCM by modifying the material properties, such as conductivity, density and specific heat. However, the results seem not normal, because it different with the real measurement. I think I made a mistake but I still don’t know what it is

1 Like
5

Hi Yanayuliana.
Assalamu alaikum.
I could edit your file and run the simulation after reading through tons of documents and forum help. I edited the script and added new PCM properties to your solution. You can enhance the script as there as several warnings, but it runs well. It will be difficult to explain everything. I can explain via a Zoom call or other means if you wish to. You can check the idf I edited.
—Changed timestep to 30
—Changed PCM properties and added MaterialProperty: PhaseChange
—Removed GENERIC PAINTED MATERIAL layers and Air Gap as well.
—Changed to ConductionFiniteDifference for heat transfer equation

Thanks for the issue you mentioned. I could explore new things in the meantime.
pcm_trial.idf (384.0 KB)

6

wa’alaikumussalam. hey it’s very kind of you.
sure, I’ll check it first and we can manage a zoom call for further explanation.

1 Like
7

Hi Meftah…
Hope you are doing well… I would like to ask you for the PCM modelling set up if possible? are you still available and willing to help ?

Abeer

8

Hi Abeer,
I am doing good. Thanks for asking.
Please let me know in details. In which part you are having trouble?

9

Hi Meftah,

Thanks for your response! I’ve tried to follow the setup instructions for the PCM definition in Grasshopper as precisely as possible, but I’m still running into an issue. I’m not sure where the problem might be, so I’m sharing my Grasshopper file here. If you have a chance to take a look, I’d appreciate any insights you might have on where things could be going wrong.

Additionally, I’d love some advice on reading the simulation results—specifically on how the PCM is expected to impact indoor temperature and energy usage. Any pointers on interpreting these outcomes would be super helpful!
pcm.3dm (704.6 KB)
pcm.gh (238.2 KB)

Thanks again for your help!

10

@meftah416 …Reminder