Wyniki wyszukiwania - Biblioteka Nauki

1

Zastosowanie CFD w ocenie drożności górnych dróg oddechowych

100%

Marków M. , Janecki D. , Misiołek M. , Warmuziński K.

Polski Przegląd Otorynolaryngologiczny

|

2016

|

tom 5(3)

24-27

PL

Obliczeniowa dynamika płynów (CFD) to szybko rozwijająca się dziedzina nauki, mająca szereg zastosowań praktycznych. Od lat używana jest w aerodynamice, inżynierii, hydraulice, meteorologii, budownictwie oraz wielu innych dziedzinach. Pierwsze publikacje dotyczące użycia CFD w medycynie dotyczyły przede wszystkim pulmonologii i kardiologii, czyli dziedzin, w których dynamiczne właściwości gazu i płynu odgrywają ważną rolę w prawidłowym funkcjonowaniu organizmu. W laryngologii CFD umożliwia pomiar oraz wizualizację dynamicznie zmieniających się parametrów przepływu powietrza w górnych drogach oddechowych

2

Computational Fluid Dynamics calculation of a planar solid oxide fuel cell design running on syngas

75%

Pianko-Oprych P. , Zinko T. , Jaworski Z.

Chemical and Process Engineering

|

2017

|

tom Vol. 38, nr 4

513--521

EN

The present study deals with modelling and validation of a planar Solid Oxide Fuel Cell (SOFC) design fuelled by gas mixture of partially pre-reformed methane. A 3D model was developed using the ANSYS Fluent Computational Fluid Dynamics (CFD) tool that was supported by an additional Fuel Cell Tools module. The governing equations for momentum, heat, gas species, ion and electron transport were implemented and coupled to kinetics describing the electrochemical and reforming reactions. In the model, the Water Gas Shift reaction in a porous anode layer was included. Electrochemical oxidation of hydrogen and carbon monoxide fuels were both considered. The developed model enabled to predict the distributions of temperature, current density and gas flow in the fuel cell.

3

Zjawisko lewitacji akustycznej – badania wstępne

75%

Grzywnowicz K. , Remiorz L.

Rynek Energii

|

2020

|

tom Nr 1

51--58

PL

Zjawiska lewitacji stanowią potencjalnie interesującą alternatywę dla wielu rozwiązań tradycyjnych i są przedmiotem szerokich badań. Istota lewitacji polega na równoważeniu siły grawitacji innym oddziaływaniem, np. magnetycznym. Jako przykład praktycznego wykorzystania tego fenomenu można wymienić chociażby łożyska wykorzystujące zjawisko lewitacji magnetycznej. Inną metodą uzyskania efektu lewitacji jest oddziaływanie falą akustyczną. Powstająca w tym przypadku siła nośna wywołana jest niezerową wypadkową sumarycznego ciśnienia wywołanego oddziaływaniem fali akustycznej na powierzchni lewitującego ciała. W pracy omówiono podstawy fizyczne zjawiska lewitacji akustycznej oraz potencjalny obszar jego zastosowań w energetyce. Przedstawiono również wstępne wyniki badań modelowych, obejmujących wyznaczenie wpływu podstawowych parametrów środowiskowych, w tym względnego położenia lewitującego ciała, częstotliwości fali akustycznej oraz wilgotności gazu roboczego, na wartości charakterystycznych parametrów zjawiska, w tym maksymalnej siły nośnej. Otrzymane wyniki wskazują na możliwość wykorzystania zjawiska przy zmiennych właściwościach fizycznych gazu roboczego, pod warunkiem ograniczenia masy lewitującej drobiny. Rezultaty wykazują jednocześnie graniczne wartości parametrów środowiskowych, które można uznać za akceptowalne w przypadku wykorzystania omawianego fenomenu. Zebrane dane uwidaczniają fundamentalną zależność siły nośnej od położenia lewitującej drobiny w kanale akustycznym oraz częstotliwości fali akustycznej. Wyniki badań prezentują także ograniczony wpływ wilgotności gazu na parametry zjawiska.

EN

Since the levitation phenomena are potentially interesting alternative to many traditional solutions, they state currently a subject of extensive research. The principle of the levitation consists in balancing the force of gravity with another interaction, e.g. magnetic. As an example of the use of this phenomenon, the bearings using the phenomenon of magnetic levitation might be mentioned. Another method of obtaining the effect of levitation is acoustic wave interaction. The lift force generated in this case is caused by a non-zero resultant vector of the total pressure caused by the impact of the acoustic wave on the surface of the levitating body. The paper discusses the physical foundations of the phenomenon of acoustic levitation and the potential area of its applications in energy. Preliminary results of model tests, including determination of the impact of basic environmental parameters, including the relative position of the levitating body, frequency of the wave and humidity of the gas, on the values of the characteristic parameters of the phenomenon, including the maximum lift are presented. The obtained results indicate the possibility of using the phenomenon with variable physical properties of the working gas, provided limited the mass of levitat-ing particles. Simultaneously, the results show the limit values of environmental parameters that can be considered acceptable when the phenomenon in question is used. The collected data show the fundamental dependence of the lift force on the position of levitating particles in the acoustic channel and the frequency of the acoustic wave. The test results also present a limited effect of gas humidity.

4

Influence of cavity edges shape on flow induced noise

75%

Łojek P. , Suder-Dębska K. , Mach M.

Vibrations in Physical Systems

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2021

|

tom Vol. 32, nr 1

art. no. 2021110

EN

In this paper, impact of the cavity shape on flow-generated noise is analysed. As reference model, the classic rectangular cavity with perpendicular corners was used. The impact of both upstream and downstream edges was analyzed. In this paper, authors used hybrid method, where the flow was computed by means of Spalart-Allmaras Detached Eddy Simulations (DES) model, and the acoustic wave propagation was calculated by Curle acoustic analogy.

5

Determination of coefficients of thermal convection in a highspeed electrical machine using the computational fluid dynamics

75%

Kolondzovski Z.

Przegląd Elektrotechniczny

|

2010

|

tom R. 86, nr 12

68-71

EN

This paper presents a method based on the Computational Fluid Dynamics (CFD) for modelling the turbulent and thermal properties of the flow for cooling of a high-speed electrical machine. The method estimates the coefficients of thermal convection on the cooling surfaces of the machine, as well as the temperature and velocity fields of the coolant. The local values of the coefficients of convection are estimated for all of the cooling surfaces of the machine, including separate determinations for their inlet and outlet parts.

PL

W artykule przedstawiono metodę bazującą na obliczeniowej dynamice płynów dla zamodelowania turbulentnych i cieplnych właściwości przepływu chłodzącego wysokoobrotowe maszyny elektryczne. Metoda pozwala oszacować współczynniki konwekcji cieplnej z chłodzonych powierzchni maszyny, jak również pole temperaturowe i pole prędkości czynnika chłodzącego. Lokalne wartości współczynników konwekcji oszacowuje się dla wszystkich chłodzonych powierzchni maszyny, włączając też ich części wlotu i wylotu.

6

Three-dimensional computational fluid dynamics modelling of a proton exchange membrane fuel cell with a serpentine micro-channel design

75%

Zinko T. , Jaworski Z. , Pianko-Oprych P.

Chemical and Process Engineering

|

2018

|

tom Vol. 39, nr 2

143-–154

EN

The aim of this paper was to demonstrate the feasibility of using a Computational Fluid Dynamics tool for the design of a novel Proton Exchange Membrane Fuel Cell and to investigate the performance of serpentine micro-channel flow fields. A three-dimensional steady state model consisting of momentum, heat, species and charge conservation equations in combination with electrochemical equations has been developed. The design of the PEMFC involved electrolyte membrane, anode and cathode catalyst layers, anode and cathode gas diffusion layers, two collectors and serpentine micro-channels of air and fuel. The distributions of mass fraction, temperature, pressure drop and gas flows through the PEMFC were studied. The current density was predicted in a wide scope of voltage. The current density – voltage curve and power characteristic of the analysed PEMFC design were obtained. A validation study showed that the developed model was able to assess the PEMFC performance.

7

Obliczeniowa dynamika płynów w analizie zagadnień smarowania hydrodynamicznego

75%

Dąbrowski L. , Rotta G. , Wasilczuk M.

Tribologia

|

2008

|

tom nr 2

137-143

PL

Współczesne systemy obliczeniowe obliczeniowej dynamiki płynów (ang. Computational Fluid Dynamics - CFD) i szybkie komputery zwiększają możliwości rozwiązywania dotychczas nierozwiązanych problemów hydrodynamicznej teorii smarowania. Z drugiej jednak strony wykorzystywanie systemów CFD do rozwiązywania złożonych zagadnień smarowania hydrodynamicznego nie jest zadaniem prostym. Systemy obliczeniowe były rozwijane do rozwiązywania zróżnicowanych zadań i w przypadku smarowania hydrodynamicznego konieczne jest specjalne podejście, aby uniknąć problemów numerycznych i otrzymywać wiarygodne wyniki. W początkowych etapach badań przeprowadzono badania wpływu gęstości podziału modelu CFD na wyniki, porównywano uzyskiwane wyniki ze znanymi rozwiązaniami analitycznymi itp. ([L. 1, 2]). Kolejnym analizowanym zagadnieniem jest wpływ konstrukcji przestrzeni między segmentami łożyska wzdłużnego i zachodzących w nich zjawisk na temperaturę środka smarowego w strefie wlotowej i, co za tym idzie, właściwości łożyska.

EN

Despite the fact that hydrodynamic theory is over one hundred years old, and numerical simulations have been applied in early 1960's, there are still a lot of problems which are not solved. Very often their origin lies in the nature of other phenomena accompanying lubricant flow in the film, such as fluid flow in the groove between and around bearing pads or heat transfer in whole bearing system. Nowadays, modern Computational Fluid Dynamics (CFD) codes, both commercial and freeware and very fast computers enhance the possibilities of solving some problems that have been impossible to solve up till now. On the other hand application of CFD codes for solving advanced lubrication problems is not a straightforward task. General-purpose CFD codes have been devised for solving a large variety of problems and in case of specific features of film lubrication special approach is necessary to obtain relevant results and avoid numerical problems. The authors attempt to utilise CFD codes for the calculations of hydrodynamic thrust bearings. In this paper some aspects of CFD applications are discussed. The discussed aspects comprise convergence criteria, mesh size and type of flow.

8

A new tool for topological optimization of a rotor for vertical axis wind turbines

75%

Jakubowski M. , Fritzkowski P.

Vibrations in Physical Systems

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2016

|

tom Vol. 27

143--150

EN

A computer program for topological optimization of a rotor for vertical axis wind turbines of various type is presented. The tool is based mainly on two external modules: the GMSH mesh generator and the OpenFOAM CFD toolbox. Interpolation of rotor blades geometry and computational model of the airflow through a turbine are briefly discussed. Moreover, a simple optimization algorithm is described. Exemplary results for a H-type rotor are presented. Finally, potential directions for the software development are indicated.

9

On a method of efficiency increasing in Kaplan turbine

75%

Banaszek M. , Tesch K.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

|

2011

|

tom nr 140

29-38

EN

This paper presents a method of increasing efficiency in Kaplan-type turbine. The method is based on blade profile optimisation together with modeling the interaction between rotor and stator blades. Loss coefficient was chosen as the optimisation criterion, which is related directly to efficiency. Global optimum was found by means of Genetic Algorithms, and Artificial Neural Networks were utilized for approximations to reduce long calculation time.

10

Numerical Analysis of a Small-Size Vertical-Axis Wind Turbine Performance and Averaged Flow Parameters Around the Rotor

75%

Rogowski K. , Maroński R. , Piechna J.

Archive of Mechanical Engineering

|

2017

|

tom Vol. LXIV, nr 2

205--218

EN

Small-scale vertical-axis wind turbines can be used as a source of electricity in rural and urban environments. According to the authors’ knowledge, there are no validated simplified aerodynamic models of these wind turbines, therefore the use of more advanced techniques, such as for example the computational methods for fluid dynamics is justified. The paper contains performance analysis of the small-scale vertical-axis wind turbine with a large solidity. The averaged velocity field and the averaged static pressure distribution around the rotor have been also analyzed. All numerical results presented in this paper are obtained using the SST k- ω turbulence model. Computed power coefficients are in good agreement with the experimental results. A small change in the tip speed ratio significantly affects the velocity field. Obtained velocity fields can be further used as a base for simplified aerodynamic methods.

11

Simulation of start-up behaviour of a passive autocatalytic hydrogen recombiner

75%

Rożeń A.

Nukleonika

|

2018

|

tom Vol. 63, No. 2

27--41

EN

Heterogeneous catalytic recombination of hydrogen with oxygen is one of the methods used to remove hydrogen from the containment of a light-water nuclear reactor (LWR). Inside a passive autocatalytic recombiner (PAR), hydrogen and oxygen molecules are adsorbed at catalyst active spots and they recombine to yield water. Heat released in this exothermic reaction creates natural convection of gas in the spaces between the elements supporting a catalyst. Hot and humid gas fl ows upwards into the PAR chimney, while fresh, hydrogen-rich gas enters the PAR from below. Catalytic recombination should start spontaneously at room temperature and low hydrogen concentration. Computational fl uid dynamics (CFD) has been used to study the dynamic behaviour of a plate-type Areva FR-380 recombiner in a quiescent environment for several test scenarios, including different rates of increase in hydrogen concentration and temporary catalyst deactivation. A method for the determination of pressure boundary conditions at the PAR exits was proposed and implemented into a CFD code. In this way, transient operation of PAR could be simulated without the need to model gas circulation outside the device. It was found that fi rst a slow downward fl ow of gas is developed, which may persist until the temperature of the catalyst foils rises. As soon as the gas inside the PAR absorbs enough heat to become lighter than the gas outside the PAR, it starts to fl ow upwards. Criteria for determining the start-up time of PAR were proposed. Model predictions were also compared with experimental data obtained in tests conducted at the THAI facility.

12

Influence of the position of the distal pressure measurement point on the Fractional Flow Reserve using in-silico simulations

75%

Agujetas R. , Ferrera C. , González-Fernández R. , Nogales-Asensio J. M. , Fernández-Tena A.

Biocybernetics and Biomedical Engineering

|

2023

|

tom Vol. 43, no. 1

69--81

EN

Coronary stenosis is mainly responsible for myocardial ischemia as the blood supply to a portion of the heart stops or is severely reduced. The Fractional Flow Reserve is the benchmark for the hemodynamic significance assessment of coronary stenoses. Its value is employed as a gatekeeper/planning tool for revascularization in clinical practice. Non-invasive alternatives have been successfully proposed to guide cardiologists. However, simulation values are not accurate enough in the 0.75-0.85 range, so invasive Fractional Flow Reserve should be used. Several authors argue about where distal pressure should be measured. Therefore, our aim is to use simulation to assess how this value changes and to detect the correct measurement region. First, we have adjusted the simulation method to the segmentations of two patients whose invasive Fractional Flow Reserve is known. We then extended our analysis to four patients and obtained the simulated value at multiple points distal to the stenosis. This is an advantage over invasive measurements, whose locations are restricted. The results are also essential for locating the best region for invasive distal pressure measurements. We propose a hybrid invasive and in-silico procedure that would avoid false results and prevent cardiologists from making erroneous clinical decisions.

13

Analysis of wall shear stress around a competitive swimmer using 3D Navier-Stokes equations in CFD

63%

Popa C. V. , Zaidi H. , Arfaoui A. , Polidori G. , Taiar R. , Fohanno S.

Acta of Bioengineering and Biomechanics

|

2011

|

tom Vol. 13, no. 1

3-11

EN

This paper deals with the flow dynamics around a competitive swimmer during underwater glide phases occurring at the start and at every turn. The influence of the head position, namely lifted up, aligned and lowered, on the wall shear stress and the static pressure distributions is analyzed. The problem is considered as 3D and in steady hydrodynamic state. Three velocities (1.4 m/s, 2.2 m/s and 3.1 m/s) that correspond to inter-regional, national and international swimming levels are studied. The flow around the swimmer is assumed turbulent. The Reynolds-averaged Navier-Stokes (RANS) equations are solved with the standard k-u turbulent model by using the CFD (computational fluid dynamics) numerical method based on a volume control approach. Numerical simulations are carried out with the ANSYS FLUENTŽ CFD code. The results show that the wall shear stress increases with the velocity and consequently the drag force opposing the movement of the swimmer increases as well. Also, high wall shear stresses are observed in the areas where the body shape, globally rigid in form, presents complex surface geometries such as the head, shoulders, buttocks, heel and chest.

14

Computational fluid dynamics modelling of short timebottle filling process

63%

Jałowiecka M. , Makowski Ł.

Chemical and Process Engineering

|

2020

|

tom Vol. 41, nr 2

143-–163

EN

Every change in the bottle geometry as well as every change of physical and rheological properties posesa risk of excessive gas entrainment during a filling process. To maintain satisfactory filling efficiencythere is a need to optimise this process with respect to all adverse phenomena which affect the fluidflow, such as spluttering on the bottom, air caverns formation and air entrainment with incoming liquid.This paper comprises numerical simulations of two filling methods. The first method involves dosingwith a pipe placed over the free liquid surface of a fully filled bottle. The second method covers fillingwith a pipe located near the bottom. Moreover, the influence of rheological properties and surfacetension values is considered. The comprehensive analysis of amount of entrained air represented byair volume fraction in dispensed liquid let the authors define the influence of filling speed on themechanism and amount of entrapped air.

15

Mathematical Modelling of Pneumatic Melt Spinning of Isotactic Polypropylene. Part 1, Modelling of the Air Jet Dynamics

63%

Zachara A. , Lewandowski Z.

Fibres & Textiles in Eastern Europe

|

2008

|

tom Vol. 16, no. 4 (69)

17--23

EN

In this series of publications, the process of nonwoven melt blowing of ultra-fine fibers is presented. The process starts in the dual slot die where two converging air jets draw the molten polymer stream. In the present paper (Part I), the air flow field is investigated with the aid of the k – ε turbulence model, which is solved numerically. From the results of computations, we have distributions of the air flow parameters along the z – axis, which is also the axis of pneumatic melt spinning. These parameters are the air velocity, temperature and pressure, which will be used in Part II and III to compute the fiber melt blowing dynamics.

PL

Praca stanowi część pierwszą serii trzech publikacji, w których przedstawiono matematyczne modelowanie procesu pneumatycznego przędzenia włóknin ze stopionego polimeru typu „melt blowing”. Proces ten zachodzi pod wpływem podwójnego, zbieżnego strumienia gorącego powietrza wydmuchiwanego symetryczne z dysz powietrznych z obu stron belki przędzalniczej. W niniejszej publikacji (Część I) przedstawiono badanie pola aerodynamicznego strumienia powierza metodą numeryczną z zastosowaniem modelu turbulentnego k – ε. W wyniku obliczeń otrzymano rozkłady parametrów pola przepływu powietrza wzdłuż centralnej osi strumienia, która jest też osią przędzenia. Parametrami tymi są prędkość, temperatura i ciśnienie powietrza, których rozkłady wzdłuż osi przędzenia będą zastosowane w modelowaniu dynamiki procesu pneumatycznego przędzenia włóknin ze stopu izotaktycznego polipropylenu w częściach II i III serii publikacji.

16

Computational fluid dynamics and experimental hydrodynamic analysis of a solar AUV

63%

Asadi Asrami E. , Moonesun M. , Azizi Abi F.

|

tom Vol. 28, no. 1

57--77

EN

In the present study, the effect of free surface on the hydrodynamic forces acting on themotion of an autonomous underwater vehicle (AUV) has been investigated. The AUVis powered by solar energy. Using computational fluid dynamics, the Reynolds averaged Navier Stokes (RANS) equations for the flow around the AUV are solved, and the freesurface effect is simulated using the volume of fluid (VOF) two-phase flow model. Forthis purpose, the commercial code ANSYS FLUENT 18 was used [1]. The results ofthe numerical solution are compared with experimental results of the AUV model in thesurface motion in the towing tank of the Persian Gulf National Laboratory with a scaleof 1:1. The experiment was performed in a fixed draft and the velocity was ranging from 0.2 m/s to 1.4 m/s (according to Reynolds number 2.4 x 105 to 1.7 x 106).

17

Straty ciśnienia na zaworze antyskażeniowym - badania laboratoryjne i modelowe

63%

Widomski M. K. , Musz A. , Iwanek M.

|

2012

|

tom Nr 9

380-385

PL

Artykuł zawiera wyniki badań laboratoryjnych i modelowych mających na celu określenie straty ciśnienia oraz współczynnika oporu miejscowego dla zestawu zaworu antyskażeniowego o średnicy nominalnej DN 15 mm, obejmującego także połączenia rozłączne zawór - przewód PEX-A1-PEX, dla zmiennej wartości liczby Reynoldsa. Badania numeryczne rozkładu prędkości przepływu wody oraz intensywności turbulencji zostały przeprowadzone za pomocą komercyjnego oprogramowania CFD (Computational Fluid Dynamics) FLUENT, Ansys Inc. Przeprowadzone badania pozwoliły na określenie zależności pomiędzy wysokością straty ciśnienia a liczbą Reynoldsa oraz na identyfikację zmian we właściwościach przepływu wody przez zawór antyskażeniowy wpływających na wartość strat ciśnienia na badanym oporze miejscowym. Wyniki zaprezentowanych obliczeń numerycznych mogą także zostać wykorzystane do analiz numerycznych wymywania i rozprzestrzeniania się zanieczyszczeń migrujących z materiału korpusu i uszczelnienia zaworu.

EN

This paper presents the results of laboratory and modeling studies of pressure drop and coefficient of pressure loss for the set of anti-pollution non-return valve of nominal diameter DN 15 (valve - PEX-A1-PEX pipe connections were the part of testing set) conducted for variable range of Reynolds number. Numerical researches of water flow velocity distribution and flow turbulence intensity inside the tested value were conducted by commercial CFD (Computational Fluid Dynamics) software - FLUENT, Ansys Inc. Our studies allowed to determine the relation of pressure drop coefficient to Reynolds number and to identify the changes in water flow characteristics resulting in pressure loss. Results of the presented modeling calculations may be also applied in numerical analyses of pollutants migration to water from valve body and sealing materials.

18

Numerical study on flow topology and hemodynamics in tortuous coronary artery with symmetrical and asymmetrical stenosis

63%

Song J. , Kouidri S. , Bakir F.

Biocybernetics and Biomedical Engineering

|

2021

|

tom Vol. 41, no. 1

142--155

EN

Tortuosity in coronary artery has been found to be greatly related to the potential sites of stenosis in these last years. Many investigations have been carried out based on the tool of Computational Fluid Dynamics (CFD) mainly focusing on the influences of curved artery in blood flow. Within the limited investigations of coupling between stenosis and tortuosity, the stenosis has been considered to be located at the tortuous segment. However, with recent clinical studies, the case of stenosis occurred at non-tortuous segment before tortuosities has been confirmed which has not been paid enough attention yet. Therefore, the present study aims to investigate the disturbed streamlines and hemodynamics in curved and spiral artery considering symmetrical and asymmetrical stenosis upstream these tortuosities. Different stenosis severities, pulse rates and distances between stenosis and tortuosity as controlling parameters have been studied. The distribution of time averaged wall shear stress (TAWSS) and streamlines through tortuous segment have been displayed in order to determine the potential disease sites. Artery surface of TAWSS below critical value has been quantified as well to evaluate the risks of atherosclerosis. The results reveal that larger artery surface of TAWSS below critical value generally goes with smaller pulse rate, larger stenosis severity and distance between stenosis and tortuosity both for curved and spiral artery. However, exceptions were found in the cases of distance of 6 mm in curved artery with symmetrical stenosis and stenosis severity of 50% in spiral artery. Moreover, the spiral tortuosity tends to suppress the potential risks of atherosclerosis compared to curved tortuosity.

19

Metodyka numerycznego wyznaczania współczynników oporu nadwodnej części statku

63%

Kaup J.

Zeszyty Naukowe / Akademia Morska w Szczecinie

|

2006

|

tom nr 11 (83)

131-140

PL

Artykuł przedstawia metodykę wyznaczania współczynników sił aerodynamicznych statku z wykorzystaniem numerycznej dynamiki płynów. Obliczenia numeryczne zostały zweryfikowane z wynikami uzyskanymi w tunelu aerodynamicznym. Pokazano również sposób ułożenia siatki i jej późniejszej adaptacji w celu dopasowania jej do lokalnych warunków przepływu. Duży nacisk w prezentowanej metodyce obliczeń położono na ograniczenia czasu generowania siatki i automatyzację procesu obliczeń.

EN

The paper presents guidelines for the determination of ship aerodynamic forces with the application of computational fluid dynamics methods. Numerical calculations were verified against the results from the wind tunnel. The techniques of grid making and furhter grid adoption for local flow characteristics were discussed. Special attention was paid to the problems of time limitations during grid generation and automation of thge computation process.

20

Submarine Resistance Force Characteristics Determination After Modification of Depth Rudder System

63%

Kiciński R. , Jurczak W.

Advances in Science and Technology. Research Journal

|

2021

|

tom Vol. 15, no 1

1--9

EN

A submarine, as a technical object, has many systems which are necessary for operation. In addition to the weapon systems, there are many systems required for the safe operation under the water. The submarine steering system is one of them. The article presents the principle of operation and the modification concept of the stern rudders of the project 207 (Kobben class) submarine. On the basis of measurements, the resistance force characteristics were determined. A calculation model was proposed using CFD (Computational Fluid Dynamics) and CAE (Computer Aided Engineering) techniques to determine the resistance force characteristics during the design stage. Then, the measured resistance force characteristics were used to verify the calculation model. Using the proposed method, the resistance force characteristics for an existing submarine were determined, and then its modification was proposed. The simulation results for the modified rudder design allowed determining the reduction of the ship resistance force for the new solution. Lower resistance force means lower demand for electrical power in the engine room, which consequently affects the operational safety by increasing maneuverability and improving the immersion curve. The proposed modification enables to reduce the power consumption by about 8 kW and reduced the resistance force by 2%, which increased the ship’s autonomy.