261 



L ship 



en 



46 2 . 2min ^ 



TOWED CONDITION 



CHANGE OF TOTAL HEAD 



T ship 



gHp*/|u2 



MEASUREMENT SECTION 

 0.5Lt3p behind A. P. 



FIGURE 6. (continued). 



Thus, condition (92) is not contradictory to the 

 results of the self-propulsion test. 



5 . CONCLUSION 



From the theoretical and experimental studies for 

 the interaction of the hull and propeller, the 

 following conclusions are derived: 



(i) Flow field in the vicinity of a hull is 



analyzed by using acceleration potential, and the 

 approximate calculation method is derived. This 

 method can be used to calculate the change of 

 pressure on the hull and has a higher practical 

 applicability than conventional methods. 



(ii) For the analysis of the wake at a distant 

 position behind a ship Oseen's approximation is 

 used, and the optimum condition is given for the 

 wake energy recovery by the propeller. This 

 condition is examined by the results of the self- 

 propulsion tests and the wake survey measurements. 



