Let's say I have duct work shown as below. I have air moving from left to right with high velocity.There are two elbows and there is a damper of the same kind just before each of them and there is another one in the straight line which is closed, they are represented in the image below. Having the identical dampers, the flow rate of air downstream of the second damper is significantly higher than the first one. I have some ideas why, but still I am not sure about the path of the air near the second elbow.
Can it be because as the air will follow the least resistance path, and as this path is closed zith the damper, so there will be high turbulent flow around this elbow and most of the air will go through this elbow, or is it physically wrong?