Hydraulic Radius - An important calculation that is important for the use in finding flow rates - usually used in conjunction with the Reynolds number. There is " open channel flow " like channels and creeks As well as " closed flow " like pipes and closed vessels Reynolds number refers to the turbulence or lack of turbulence of the a fluid. < 2000 laminar > 2000 Turbulent

Fluid Dynamics is an interesting topic but is complicated and a bases of calculus knowledge and vector analysis is needed to understand this topic. To work out the problems anyways which are not the easiest of things to do.