Experimental investigation on resistance and propulsion of submerged waterjet propelled ship in model-scale

Propeller open water tests, hull resistance tests and self-propulsion tests were carried out on two ship models propelled by submerged waterjet and conventional propeller respectively. Detailed analysis was done on the variations of propulsive performances of the submerged waterjet, propeller as well as corresponding hull-propulsor systems. Results show that: (1) the propulsive efficiency of submerged waterjet in open water is equivalent to that of the propeller in model scale, with the maximum efficiency around 0.72, while the high-efficiency operation range of submerged waterjet is wider than that of propeller in open water; (2) compared with propeller ship, the simpler stern-appendage arrangement of submerged waterjet ship can effectively reduce additional hull resistance caused by stern appendages; (3) at Fr = 0.20 and Fr = 0.26, the overall propulsive efficiency of submerged waterjet ship model in self-propulsion is 64.7% and 66.1%, which is 1.2% and 5.3% higher than that of propeller ship respectively. The corresponding absorbed power of the submerged waterjet is 9.41% and 15.4% lower than that of the propeller at two speeds respectively. Generally, the submerged waterjet propelled ship shows a better performance of propulsion and energy saving. This study provides a meaningful reference for the integrated design and optimization of submerged waterjet and its corresponding hull geometry. © 2024 China Ship Scientific Research Center. All rights reserved.