Waterjet wake fraction assessment as per model test data

Труды Крыловского государственного научного центра

Olga V. Yakovleva¹  Yelena L.,Kortunova² 

[1] Krylov State Research Centre;Krylov State Research Centre;

关键词: small-size waterjet;    hydrodynamic test rig;    test tank;    wake field;    thrust;    flow rate;    wake;   

DOI  :  10.24937/2542-2324-2018-3-385-41-49

来源: DOAJ

【 摘 要 】

Object and purpose of research. This paper studies a fast displacement ship with small-size waterjet propulsors. The purpose of the study is to develop a wake fraction determination method needed to calculate hull-propulsor interaction. Materials and methods. This study is based on waterjet calculation theory fundamentals, as well as on the test data obtained for the model of small-size waterjet at hydrodynamic test rig and during self-propulsion tests in the test tank. Main results. The study yielded flow parameters of small-size waterjet model obtained at hydrodynamic test rig and during self-propulsion tests in the test tank. Wake measurements were taken near the hull, in the water inlet area of the propulsor. During the self-propulsion tests, wake assessment was performed at the entry of propulsor water duct. The study also gives advance ratio relationships for the wake fraction and the relative wake thickness in front of the inlet, as well as describes the effect of the wake and its coverage area upon inductive efficiency. It is also described how to extrapolate propulsor performance curves to the full scale taking into account boundary layer on hull bottom, along with comparison of model and full-scale wake fractions. Conclusion. The results of this study are of practical importance for waterjet design, in particular, for development of the propulsors taking water from hull surface, and also for performance curve extrapolations to the full scale taking into account boundary layer on hull bottom.

【 授权许可】

Unknown