Estimate and Mesaurement for Low Speed Propulsion Performance with Shaft Generator Motor on “Fukae Maru”

Abstract

Fukae Maru have electrical propulsion system with changing shaft generafor to motor addition to main diesel engine. But the output of motor is very smaller than that of main engine. They are of 200 kW and 1, 100 kW respectively.
When the ship is propelled only by shaft motor, it is important for starting the ship and increasing the speed without overload on shaf tmotor to choose the pitch angle on c. p. p.. So the sutable low speed propulsion performance was estimated by numelical calculation. Sufficient ship speed was consequently presumed with the output less than of 147 kW [200 ps] when the ship was started with the pitch angle of 7.5°and the pitch angle was increased to 10° after 54 sec. ; then the propeller revolution was constant of 226 rpm.
As a result of experiment, the output of starting became 6% higher than expected value and that of increasing pitch angle became 2. 9% higher. And the ship speed and travel distance to time coincided with the calculation.