Reply To: NA

[Rob]

You're welcome, and thanks for starting a new topic for a new question. 

1) Up to you - how high is the building relative to the ABL? What is upstream to decide if the ABL has formed or been chewed up by the scenery? 

2) Your monitor shows a roughly repeated variation every 50-ish iterations. Plot velocity contrours around the building every 5 iterations. Also pressure on the building. What do they tell you?

3) How long a transient did you run? Time step was probably well under a second, but what frequency do you expect the flow to change at?

The extra data from 2 & 3 will help you decide if the flow changes enough to need to worry about it. A transient flow may be a very small fluctuation that can be ignored, or a very big change that can't.