change for divergent nozzle, Nozzle A. The discharge coefficient curve of Nozzle A and C are identical. It can be said that the increasing effect of rounding on discharge coefficient is eliminated by nozzle divergent geometry.
Figure 4.4.1: The discharge coeeficient change
For further analyses more measurements are needed, but as a summary, it can be said that the convergent nozzles with hydro-grinding retard the onset of supercavitation and hydrogrinding increases the discharge coefficient. The measured flow experiments showed that the onset of cavitation starts after 10200, 10900, 12300, and 12100 Re number values, which correspond 80, 80, 80 and 100 MPa injection pressures for Nozzle A, B, C, and D, respectively.