It would be easier to answer if you provide more info of your problem.

Mahabat Khan Sir, I am attaching the diagram of my study. Looking forward to your suggestion.

" I found high turbulence intensity "

How did you evaluate that? What formulation are you using?

Maybe you could show a few figures on where and how the turbulent flows occur?

Filippo Maria Denaro I got the average room turbulence intensity of more than 50% but the average indoor velocity is near .055 m/s. I used the K-e model. outdoor airspeed was .4 m/s, the temp was 28 degree Cel and the wind direction was 35 degrees WSW.

Hi. I don't completely understand your question. However, take a look at papers to understat which factors can influence the TI level (roughness, changes in the geometry, temperature increase, etc.). Based on what you have attached here, I can see significant changes in your geometry (mainly balcony and opening) that can increase the TI level. In order to understand the importance of geometry in your study, I recommend you to simulate it, for example, with/without balcony and compare the situation. You will find out how changes in the geometry can play an important role in turbulent flows.

Kazi Shafrin Shahid what percentage of turbulence intensity did you use at the inlet?

First, I don't completely trust in the k-eps model and, more in general, in RANS approaches for such problems. Many further issues could be in the setting of the BCs and the grid quality. I don't know if you have only considered the wind or also buoyancy effects.

In conclusion, my suggestion is to test your setting first in a problem you have enough information to compare with. If you match accurately the test we can discuss about further things

Could you include a plot or results of the high turbulence intensity region?

Mr. Kazi Shafrin Shahid

greeting

At first you can upload the figure to show the turbulence intensity and the boundary condition for your case. where the turbulence intensity can be increased by increasing of the temperature difference between Walls and stagnation air near the wall to generate turbulence flow, so about the air temperature difference between the indoor and outdoor.

About the ventilation air can be depended on the opening window area and wind direction to the opening window, and if there is any infiltration air through the building, the opening window height, and as I show there is a parallel opening window in the other wall side where that increase ventilation air flow and decrease turbulence intensity

About the turbulence model I'm always employing K-eps model because this model it is so simple and have a good accurate when compare between practical and computational approach, and that notes was mentioned in "An Introduction to Computational Fluid Dynamics-The Finite Volume Method" by H K Versteeg.

With my respect.