Johnsson and Srfntvedt 



1) From aft end of stern post at the height considered 



2) Not working at fully loaded condition 



3) Fin, bottom 



4) Fin, top 



Pressure Fluctuations in the Afterbod y 



Measurements of the pressure fluctuations were carried out 

 at different points in the afterbody using semi-conductor strain gauge 

 transducers (ENDEVCO), see Figure 2 and Table II, having a mem- 

 brane diameter of 8 mm. 



The circuits included low pass filters (32 Hz). Accelerometers 

 were fitted to the hull close to the transducers, in order to record the 

 influence of the hull vibrations on the propeller induced pressure 

 field, [28] . 



Propeller Cavitation 



The equipment used for observation of propeller cavitation is 

 described in [4] . 



Noise Level in the Afterbod y 



A tape-recorder Tandberg TB HP was positioned in the aft 

 of the main engine room and in locations adjacent to the propeller 

 (the emergency exit channel). 



Thrust, Thrust Variations and Shaft Response were measured by 

 strain gauges (Hottinger) on the thrust bearing fundament and shaft 

 and the signals telemetered to a digital voltmeter (thrust) and a UV - 

 recorder (thrust variations). Aslo this circuit included a low pass 

 filter. 



Further, axial shaft resonances were recorded by a spring 

 transducer, working against the flange coupling between propeller and 

 intermediate shaft. 



IV. 2. Test Results 



Vibratory Response in the Structure of the Shi p 



The results of the measurements of the vibration levels at 



588 



