VAV-duct systems - simulating.

VAV - air conditioning system makes it possible to control indoor conditions even when the heat loads are changing. But this is possible only when each part of the system works as it is intended to work. When the air flow varies in a large range, it can cause situations, where pressure loss of some flow dampers are out of their operating range. This is possible especially whenthe system is large and the velocities are high. This means that the air flow is not correct. Also increasing noise levels may appear. Because of increasing lack of space, it's impossible to use large ducts to ensure systems function under all conditions. So how we can be sure that the system works?