Calculation Tools

Rehbock Weir calculate Flow

Function Rehbock for Sharp Crested weirs of the Practicum

Flow Q = (1,78 + 0,24 * h / d) * b * h^1.5 flow Q m3/s flow Q liter/s
all sizes in meters! all sizes in cm!
Height of the waterlayer above the weir
at minimal 2*d from the weir, 
h = <--input! <--input!
Width of the weir,  b = <--input! <--input!
Height of the weir above the bottom, d =  <--input! <--input!

Prandtl Tube calculate Velocity

v = c * (2g dH)^0,5 Velocity m/s
Difference between Static and Dynamic pressure  dH = mm! <--input!
Gravity,  g = m/s2 <--input!
c, in the laboratory c = 1  c = <--input!
c = correction factor for disturbtion of the flow by
the shape and the size of the Pitot device. For the
Prandtl-tubes as used in the laboratory the factor c = 1.