Hydraulic performance

The slot unit can be considered as a pipe for the purposes of the hydraulic calculations and be dimensioned according to Prandtl-Colebrook. Flow-off rates for the respective longfall are given in the diagram. 

The maximum distance between the inlet shafts/gullys is calculated from the run-off rate for the given channel gradient divided by the lateral inflow per meter length. 

The water inlet area of all profiles with standard effective length 4.00 m, for channels with profiles N-D-DN300, N-F-DN300, N-F-300/400 and N-F-200/400 is approx. 17,500 mm2/m and for profiles N-D-DN200, N-D-200/300 and N-F-200/300 it is approx. 14,900 mm2/m. For all Type K channels it is 239 cm2/m (in mm2/m: 23,900).