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Numerical simulation of the ducted propeller and application to a semi-submerged vehicle

Zou Jin, Tan Guoge, Sun Hanbing, Xu Jie, Hou Yongkang

Polish Maritime Research

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2020

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nr 2

19--29

EN

The self-propulsion test of underwater vehicles is the key technique for predicting and evaluating the navigation performance of these submersibles. In this study, the numerical simulation of a standard propeller JD7704+Ka4-70 is first presented and the results are compared with experiments to validate the numerical approaches. The reason why the propulsion efficiency of the ducted propeller is higher than that of the conventional propeller is explored. Then, the paper proposes a series of numerical simulations conducted to test the performance of the ducted propeller designed according to the JD7704+Ka4-70 in order to match with the unmanned semi-submerged vehicle (USSV), and the propeller’s open water characteristic curves are obtained. The results show a reasonable agreement with the regression analysis. Afterwards, the numerical simulations focus on a self-propulsion test of the USSV with the designed ducted propeller and the self-propulsion point is obtained. The streamlines through the hull as well as the ducted propellers are clearly obtained, together with the velocity distributions of the propeller plane. The results vividly demonstrate the hydrodynamic performance of the USSV with the designed propellers. In this paper, all the CFD simulations are based on the numerical software, Star-CCM+, and use the Reynolds-averaged Navier‒Stokes (RANS) equations with the shear stress transport (SST) k-omega turbulence model.

2

Praktyczne aspekty zastosowania otunelowanych śmigieł pchających

Ruchała P., Szafran K.

Prace Instytutu Lotnictwa

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2016

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Nr 3 (244)

257--266

PL

Fakt, że zastosowanie otunelowania wokół śmigła (lub wentylatora) może poprawić jego osiągi, jest dobrze znany i potwierdzony licznymi pracami teoretycznymi i eksperymentalnymi, zrealizowanymi także w Instytucie Lotnictwa. Otunelowanie daje również szereg innych korzyśsci np. zwiększenie bezpieczeństwa użytkowania. Należałoby się zatem spodziewać, że takie rozwiązanie zyska dużą popularność, nie tylko w lotnictwie. Tymczasem powstało tylko kilka samolotów z napędem otunelowanym. Tak mała popularność tego, pozornie korzystnego, rodzaju napędu, sugeruje istnienie pewnych poważnych wad i ograniczeń. W niniejszej pracy przedstawiono przykłady zastosowania wentylatora otunelowanego, omówiono jego zasadę dzialania na przykładzie napędu izolowanego oraz przedyskutowano wpływ obecności kadłuba na warunki pracy wentylatora (w przypadku układu pchającego). Autorzy oparli się na informacjach dostępnych w literaturze oraz na własnych doświadczeniach w projektowaniu, modelowaniu, budowie i eksploatacji z napędami otunelowanymi do samolotów, śmigłowców, motolotni i poduszkowców.

EN

It is well known that an application of the duct around a fan or a propeller may improve its performance. The duct gives also several other benefits. One could expect that this propulsion will become popular, not only in aviation. Meanwhile only a few airplanes powered by ducted fans have been designed. So low popularity of this propulsion means that it may have some significant limitations. The following paper is an attempt to encapsulate the advantages and disadvantages of the ducted fans and ducted propellers applied as pushers. The authors based on their own experience and on the literature. Many years of experience in the design, modeling, construction and operation of drives by duct fan aircraft, helicopters, ultralight aircraft and hovercraft can draw conclusions that can be helpful in the design process of new construction.

3

Experimental investigation of a variable geometry ducted propeller

Muszyński T., Strzelczyk P.

Advances in Science and Technology. Research Journal

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2013

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Vol. 7, nr 17

56--61

EN

The paper presents preliminary results of experimental research on the variable geometry of a ducted propeller. The purpose of this work is explore the area of application of the ducted propellers of variable geometry. The paper contains the description of a test station and a model, initial tests’ results of some selected geometries intakes and exit vents in comparison with an open propeller.