Analysis of scale effect on the propulsion discrepancy of a four-waterjet system

• Published in: Ocean engineering Vol. 308; p. 118276
• Main Authors: Gong, Jie, Dai, Yuan-xing, Chen, Wei
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.09.2024
• Subjects: Four-pump system; Full-scale; Hydrodynamics; Scale effect; Waterjet; Hydrodynamics; Waterjet; Full-scale; Scale effect; Four-pump system
• ISSN: 0029-8018; 1873-5258
• DOI: 10.1016/j.oceaneng.2024.118276

This paper focuses on the scale effect on the propulsion discrepancy and the correlating flow characteristics of a high-speed ship with four waterjets. The propulsion discrepancy of a four-waterjet-propelled ship in model test is observed in previous study (Gong et al. Ocean Eng. 2019, 180, 211–222). Current study further performs a systematic analysis of the scale effect on several hydrodynamic coefficients (net thrust, lateral/vertical forces and torque) and flow field details (velocity, TKE and pressure). It is noted that the net thrust discrepancies are amplified in model-scale simulations and tests due to the scale effect, and the lateral/vertical force discrepancies of waterjet units are gradually decreasing with the increase of advanced speed in both scales. Stable hydraulic performance of the inner and outer pumps is observed although there are minor differences in the inflow quality, while stronger turbulence intensity exists near the channel faces in full scale due to the induction effect of the impeller. •Analyze the scale effect on the propulsion discrepancy and the correlating flow features for a four-waterjet-propelled ship.•Propose the numerical strategy for hydrodynamic performance prediction of multi-scale waterjet ship.•Provide reference for anti-cavitation and low-noise design of waterjet propulsion.