Propeller Excitation and Response of 230000 TDW Tankers 



NATURAL FREQUENCIES, AXIAL VIBRATIONS 



T/T "THORSHAMMER," CALCULATED 



THRUST VARIATION OF 10th AND 15th ORDER: ± 22 MET. TONS 



q q T/T "NORSE KING," CALCULATED 



THRUST VARIATION OF 6th ORDER: ± 20 MET. TONS 



1100 



?. T7T 



2 3 4 



THRUST BEARING STIFFNESS 10' 6 K T (kp/cm) 



Figure 9 Axial mode of shaft vibration. Natural frequency of actual 

 vibrations 



627 



