Cress Help - Jets - Propeller jets - Main propeller - A20.1

RHK / Motorship 

For RHK-ships and motor ships RT is determined as follows:

             (equation 1)

with : 

                   (equation 2)

                    

                                                     (equation 3)

 

in which :

For C1 and C2 the following values were taken:

  • C1 = 3.510-3 for a loaded ship
  • C1 = 2.010-3 for an empty ship
  • C2 = 0.1410-3 for loaded and empty ships

The following values can be taken for CM:

  • CM = 1.0 for push barge convoys
  • CM = 0.9 for motor ships according to the CEMT classification
  • CM = 0.75 for tugs and service vessels.

For the calculation of Vship, Äh and ur reference should be made to calculation rule 19 "Ship induced water movements ". Naturally for the calculation of the propeller jet load the same value for AM must be entered that used to determine Vship, Äh and ur.