Wyniki wyszukiwania - BazTech

1

The hybrid concept of turboshaft engine working according to Humphrey cycle dedicated to variety power demand - CFD analysis

Tarnawski Piotr

Combustion Engines

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2023

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R. 62, nr 2

129--136

EN

The paper presents a new concept of the turbine engine in the area of pressure gain combustion (PGE). The engine works according to Humphrey’s cycle. Minor modification in construction has allowed power generation of 500 kW, 700 kW, 1000 kW, and 1800 kW. The concept successfully resolved the challenges related to the temporary opening and closing of the combustion chamber. The presented valve timing system has ensured effective gas flow and what stands behind it, an effective process of conversion of a high-pressure gas impulse into mechanical energy. Rotating combustion chambers enabled the application of an effective sealing system. The concept characterizes simple construction and potentially low power-to-weight coefficient. The CFD numerical analysis of the presented engine concept showed very promising effective efficiency and low specific fuel consumption.

2

Deposition effect of carbon deposits on charge flow in EGR valve equipped CI engine

Woźniak Marek, Siczek Krzysztof, Zakrzewski Sergiusz, Just Paweł, Ozuna Gustavo, Onescu Constantin

Combustion Engines

|

2023

|

R. 62, nr 1

26--35

EN

The exhaust gas recirculation (EGR) valve regulates the exhaust gas flow between the engine exhaust manifold and the inlet one. This allows the inlet air to warm up, improving fuel evaporation and reducing the combustion temperature of the charge. Such a valve reduces the number of harmful substances in the exhaust gases. The valve tends to stick when too much sediment builds on the walls of the exhaust system, especially during driving in urban conditions or when leaks in the vacuum or exhaust pipes occur. A faulty valve causes the engine to run unevenly at idle speed and under light loads. The defective EGR valve weakens the inlet manifold capacity, increases combustion, causes clogging of the particulate filter and damage to the lambda probe. Blocked EGR valve may lead to engine immobilization as a result of its computerized control system operations. A model of an EGR valve for a selected diesel engine was developed to determine velocity distribution of the load flowing in it for different values of the degree of valve opening and the volume of deposits on the valve walls. The volume of accumulated carbon deposits on the walls of the EGR valve was measured using a real engine. Based on the recorded mileage of the vehicle, the assumed average speed of the car and the driving style of the driver and the intensity of deposition of carbon particles on the walls was estimated.

3

Numerical calculations of water drop using a firefighting aircraft

Czyż Zbigniew, Karpiński Paweł, Skiba Krzysztof, Bartkowski Szymon

Applied Computer Science

|

2023

|

Vol. 19, no 3

47--63

EN

The study involved a numerical analysis of the water dropping process by fixed-wing aircraft. This method, also known as air attack, is used for aerial firefighting, primarily in green areas such as forests and meadows. The conducted calculations allowed for the analysis of the process over time. The calculations were performed based on a SolidWorks model of the M18B Dromader aircraft. After defining the computational domain and setting the boundary conditions, the simulations were carried out using the ANSYS Fluent software. The resulting water dropping area was used to analyze the intensity of water distribution. The volumetric distribution and airflow velocity distribution were analyzed for specified time steps. The boundary layer where air no longer mixes with water during the final phase of water dropping was also determined. The obtained results provide an important contribution to further analyses aimed at optimizing the water dropping process by fixed-wing aircraft.

4

Wyznaczenie obciążeń wiatrem dla budynku wysokiego o złożonej geometrii z wykorzystaniem analizy przepływu CFD

Okoński Robert, Ambroziak Andrzej

Przegląd Budowlany

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2022

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R. 93, nr 11-12

42--51

PL

W pracy poruszono tematykę wykorzystania analizy przepływu CFD do wyznaczenia obciążeń wiatrem dla budynku wysokiego o złożonej geometrii przestrzennej. Przedstawione wyniki obliczeń analitycznych dla budynku wysokiego porównano z wynikami obliczeń numerycznych wykonanych w programie R-Wind Simulation. Dokonano analizy optymalizacji geometrycznej kształtu budynku w zakresie wpływu kąta skrętu (modyfikacja typu makro) i zaokrąglenia/fazowania narożników (modyfikacja typu mikro) na wypadkowe siły od obciążenia wiatrem oraz na aerodynamiczne współczynniki sił. Całość wyników podsumowano i sformułowano wnioski w odniesieniu do wyznaczania wielkości obciążenia wiatru działającego na budynek wysoki.

EN

The paper addresses the use of CFD flow analysis to determine wind loads for a tall building with complex spatial geometry. The presented results of analytical calculations for a tall building were compared with the results of numerical calculations performed in the R-Wind Simulation program. The geometric optimization of the building shape was analyzed in terms of the influence of the turning angle (macro-type modification) and corner rounding (micro-type modification) on the resultant forces from wind loads and on the aerodynamic force coefficients. All the results were summarized and conclusions were formulated concerning wind load acting on a tall building with complex geometry.

5

Analiza porównawcza sposobów wyznaczania obciążeń wiatrem na podstawie norm projektowych i analizy przepływu CFD

Okoński Robert, Ambroziak Andrzej

Przegląd Budowlany

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2022

|

R. 93, nr 3-4

46--57

PL

W pracy poruszono tematykę wykorzystania analizy przepływu CFD do wyznaczania obciążeń wiatru na konstrukcje. Przedstawiono analizę trzech modeli budynków o dachu dwuspadowym o różnych kątach nachylenia, dla których dokonano porównania wielkości współczynników parcia z wynikami dostępnymi w literaturze. Obliczenia analityczne wykonano zgodnie z normą z PN-EN 1991-1-4, natomiast obliczenia numeryczne wykonano w programie R-Wind Simulation. Całość wyników podsumowano, a wnioski sformułowano w odniesieniu do tematyki rozwiązania problemu szacowania wielkości obciążenia wiatru działającego na konstrukcję.

EN

The paper addresses the use of CFD flow analysis to determine wind loads on structures. Three models of buildings with a gable roof with different angles of inclination were presented, for which the size of the pressure coefficients was compared with the results available in the literature. The analytical calculations were made in accordance with the PN-EN 1991-1-4 standard, while the numerical calculations were made in the R-Wind Simulation program. All the results were summarized and the conclusions were formulated in relation to the problem of solving the problem of estimating the size of the wind load acting on the structure.

6

Rotating combustion chambers as a key feature of effective timing of turbine engine working according to Humphrey cycle – CFD analysis

Tarnawski Piotr, Ostapski Wiesław

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2022

|

Vol. 70, nr 5

art. no. e143100

EN

The paper presents a concept of a new turbine engine with the use of rotating isochoric combustion chambers. In contrast to previously analyzed authors’ engine concepts, here rotating combustion chambers were used as a valve timing system. As a result, several practical challenges could be overcome. An effective ceramic sealing system could be applied to the rotating combustion chambers. It can assure full tightness regardless of thermal conditions and related deformations. The segment sealing elements working with ceramic counter-surface can work as self-alignment because of the centrifugal force acting on them. The isochoric combustion process, gas expansion, and moment generation were analyzed using the CFD tool (computational fluid dynamics). The investigated engine concept is characterized by big energy efficiency and simple construction. Finally, further improvements in engine performance are discussed.

7

Computational fluid dynamics analysis of 1 MW steam turbine inlet geometries

Koprowski Arkadusz, Rzadkowski Romuald

Archives of Thermodynamics

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2021

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Vol. 42, no 1

35--55

EN

This paper analyses the influence of three different ring-type inlet duct geometries on the performance of a small 1 MW backpressure steam turbine. It examines the efficiency and pressure drop of seven turbine variants, including four spiral inlet geometries and three stages with a mass flow rate around 30 t/h. A one-pipe and two-pipe inlets are analysed from aerodynamical point of view, taking into account stator and rotor blades in three stages without the outlet. An outlet is added to the best variant. Also analysed is the occurrence of vortices in the inlets of the studied variants 1–7 as well as the efficiency, drop pressure, turbine power and mass flow. Finally, the best inlet for a 1 MW steam turbine is suggested.

8

Experimental and numerical flow analysis through arteries with stent using particle image velocimetry and computational fluid dynamics method

Tomaszewski Michal, Sybilski Kamil, Baranowski Pawel, Malachowski Jerzy

Biocybernetics and Biomedical Engineering

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2020

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Vol. 40, no. 2

740--751

EN

In the paper, an experimental and numerical flow through various kind of arteries is considered. The flow analyses are carried out on the research set up using Particle Image Velocimetry Method (PIV). The individual components of the research set up are discussed and the measurement methodology is explained. The work consists of two parts. The first one is focused on modelling numerical simulation of the stent installation procedure using an expandable balloon and the flow domain design methodology is described. In the final part, an experimental flow test on an artificial silicone vessel (diameter 3.2 mm) with a stent is performed. The results of the experimental tests are compared with a corresponding numerical simulation. The paper presents numerical simulation for two different flow domains and the results obtained from the experimental tests. In both, the experimental tests and numerical simulation, the pulsatile time dependent flow and pressure characteristic are used. Hemodynamic parameters such as the time average wall shear stress (TAWSS) and velocity vector distribution are analysed. The flow was studied at four Reynolds number values (1223; 2257; 3198; 3762) for the straight vessel and at two values for the vessel containing a stent (1223, 2257). A diameter of the vessel was 3.2 mm. Pulsating blood flow based on the data from the experimental test was analysed. During the numerical simulation it was verified which regions of the vessel had TAWSS values below 0.4 Pa. A satisfactory correlation between outcomes of the numerical simulation and the experimental test was obtained. The flow analysis is conducted in ANSYS Fluent software. Additionally, the methodology for defining the velocity profile at the entrance is presented, in order to form the velocity profile in the first step of analysed cases. The study shows possibility to create a new research set up capable of testing various clinical cases of varying pressure values in the setup, or testing the effects of vessel geometrical changes, which allows observing an influence of those parameters on the fluid flow characteristic. As the analysis for the stent has shown, the regions of low TAWSS values are located in a close proximity to the stent struts.

9

Współczynniki aerodynamiczne pojazdów kolejowych w zagadnieniu oddziaływania wiatru bocznego – wprowadzenie i badania wstępne

Lalewicz Piotr, Bryja Danuta

Przegląd Komunikacyjny

|

2019

|

R. 74, nr 6

8--13

PL

W ostatnich latach, w Europie i na świecie obserwuje się dynamiczny rozwój kolei dużych prędkości. Przy rosnących prędkościach, aerodynamika pojazdów kolejowych staje się coraz bardziej istotnym zagadnieniem. W artykule odniesiono się do problemu stateczności pojazdów przy wietrze bocznym i omówiono wpływ prędkości pojazdu na to zjawisko. Do określania sił aerodynamicznych występujących w tym zagadnieniu wykorzystuje się sześć współczynników aerodynamicznych. Opisano metody służące do ich wyznaczania – badania modelowe w tunelach wiatrowych i badania numeryczne z użyciem symulacji CFD (Computational Fluid Dynamics), w odniesieniu do normy PN-EN 14067-6:2018-10 i wymagań TSI. Przedstawiono wyniki wstępnych badań własnych, których celem było rozpoznanie możliwości obliczeniowych analiz CFD jako narzędzia do numerycznego wyznaczania współczynników aerodynamicznych na potrzeby dalszych badań prowadzących do opracowania metody analizy drgań układu pociąg – most, poddanego działaniu wiatru bocznego.

EN

In recent years, dynamic development of high-speed railways is observed in Europe and in the world. Due to the train speeds increase, aerodynamics of railway vehicles becomes more and more important issue. In the paper, the cross-wind stability problem of a railway vehicle and the influence of the train speed on this phenomenon is discussed. As a derailment risk analysis requires to determine in total six cross-wind aerodynamic forces and moments acting on a given vehicle, a knowledge of six associated with them aerodynamic coefficients is a groundwork for train stability analysis. Two most common methods of analysis of air flow around trains are pointed out – wind tunnel testing and CFD method (Computational Fluid Dynamics method). Both methods are described in the paper, in reference to PN-EN 14067-6:2018-10 and TSI requirements, and later a CFD method is applied to examine a basic train model. The main aim of this preliminary research was to recognize CFD method as a tool for a further research on cross-wind-induced vibrations of a train - bridge system.

10

Influence of air velocity at inlet to the intake system on flow parameters

Andrych-Zalewska Monika, Ambroszko Wojciech, Wielki Łukasz, Ziora Krzysztof

Autobusy : technika, eksploatacja, systemy transportowe

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2019

|

R. 20, nr 12

83--87

EN

The article presents CFD (Computational Fluid Dynamics) analysis of the Ferrari 348 sports car intake system for three variants of air intake speed to the system. The article contains an analysis of the distribution of velocities and static pressures. In addition, local velocity and flow in the filtration chamber were investigated. The influence of air velocity at inlet to the intake system on the abovementioned parameters was determined. The analysis is a prelude to the study of wave phenomena occurring in the intake system, affecting the fill factor of the cylinders. Ansys Fluent software was used for analysis.

PL

W artykule przedstawiono analizę CFD (obliczeniowej dynamiki płynów) układu dolotowego samochodów sportowych Ferrari 348 dla trzech wariantów prędkości wlotu powietrza do układu. Artykuł zawiera analizę rozkładu prędkości i nacisków statycznych. Ponadto zbadano lokalną prędkość i przepływ w komorze filtracyjnej. Określono wpływ prędkości powietrza na wlocie do układu dolotowego na wyżej wymienione parametry. Analiza jest wstępem do badania zjawisk falowych zachodzących w układzie dolotowym, wpływających na współczynnik wypełnienia cylindrów. Do analizy użyto oprogramowania Ansys Fluent.

11

CFD analysis of the Ferrari 348 GTC intake system

Andrych-Zalewska Monika, Wielki Łukasz, Ziora Krzysztof

Autobusy : technika, eksploatacja, systemy transportowe

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2019

|

R. 20, nr 6

128--133

EN

The article presents CFD (Computational Fluid Dynamics) analysis of the intake system of a Ferrari 348 GTC sports car. With this system, an adequate amount of air is supplied relative to the current demand for fuel combustion. The air demand of a given engine was determined, then analyzes were carried out. The article contains an analysis of the velocity distribution: total velocities, angular velocities and static pressure distribution. In addition, local velocity and flow in the filtration chamber were determined along with the flow directions and returns as well as power lines. The cycle impact on the temperature, locations of the highest speed drop, increase in turbulence, the largest pressure differences, and modulus of elasticity were determined. This information allows to assess whether there are no unwanted phenomena occurring in the system, such as flow disturbances. The Ansys Fluent software was used for analysis.

PL

W artykule przedstawiono analizę CFD (Computational Fluid Dynamics) układu dolotowego samochodu sportowego Ferrari 348 GTC. W tym systemie dostarczana jest odpowiednia ilość powietrza w stosunku do bieżącego zapotrzebowania na spalanie paliwa. Określono zapotrzebowanie na powietrze dla danego silnika, a następnie przeprowadzono analizy. Artykuł zawiera analizę rozkładu prędkości: prędkości całkowite, prędkości kątowe i rozkład ciśnienia statycznego. Dodatkowo wyznaczono lokalną prędkość i przepływ w komorze filtracyjnej wraz z kierunkami przepływu i powrotami oraz liniami energetycznymi. Oceniono wpływ cyklu na temperaturę, lokalizację największego spadku prędkości, wzrost turbulencji, największe różnice ciśnień i moduł sprężystości. Informacje te pozwalają ocenić, czy w systemie nie występują niepożądane zjawiska, takie jak zakłócenia przepływu. Do analizy wykorzystano oprogramowanie Ansys Fluent.

12

Pulse powered turbine engine concept – numerical analysis of influence of different valve timing concepts on thermodynamic performance

Tarnawski P., Ostapski W.

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2018

|

Vol. 66, nr 3

373--382

EN

The present work is an attempt to create the concept of an engine that will combine the benefits of a pulse powered piston engine and continuously powered turbine engine. The paper focuses on the subject of pressure gain combustion (PGC). A turbine engine concept with stationary constant volume combustors, working according the Humphrey cycle, is presented. Its work has to be controlled by valve timing system. Four different valve timing concepts were analyzed. Their influence on thermodynamic performance of engine was evaluated. Different valve constructions were researched by means of 3D numerical computational fluid dynamics (CFD) simulation.

13

3D CFD fluid flow and thermal analyses of a new design of plate heat exchanger

Pianko-Oprych P., Jaworski Z.

Polish Journal of Chemical Technology

|

2017

|

Vol. 19, nr 1

17--26

EN

The paper presents a Computational Fluid Dynamics (CFD) numerical study for a new design of a plate heat exchanger with two different flow patterns. The impact of geometric characteristics of the two studied geometries of exchanger plates on the intensification process of heat transfer was considered. The velocity, temperature and pressure distributions along the heat exchanger were examined. The CFD results were validated against experimental data and a good agreement was achieved. The results revealed that geometrical arrangement of the plates strongly influence the fluid flow. An increase in the Reynolds number led to lowering the friction factor value and increasing the pressure drop. The configuration II of the plate heat exchanger resulted in lower outlet hot fluid temperature in comparison with the configuration I, which means improvement of heat transfer.

14

Laboratory investigations of stationary methane anemometer

Kruczkowski J., Krawczyk J., Ostrogórski P.

Archives of Mining Sciences

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2017

|

Vol. 62, no. 4

893--909

EN

This paper presents a new stationary device that can perform simultaneous measurements of air flow velocity and methane concentration in a mine heading (stationary methane anemometer). The test station is designed to use the instrument to test the effect of various parameters on the air-methane stream. The air velocities and methane concentrations were fed to the measuring area via an injector and recorded. The results present numerical simulations of flow phenomena that occurred during measurement experiments.

PL

W artykule zaprezentowano nowe, stacjonarne urządzenie do jednoczesnego pomiaru prędkości przepływu powietrza i stężenia metanu w wyrobisku kopalni (metanoanemometr stacjonarny). Przedstawiono stanowisko badawcze pozwalające na przeprowadzenie eksperymentów pomiarowych polegających na oddziaływaniu na przyrząd strugą mieszaniny powietrzno-metanowej o zmiennych parametrach. Zarejestrowano przebiegi prędkości i stężenia metanu podawanego do obszaru pomiarowego za pomocą iniektora. Pokazano wyniki symulacji numerycznej zjawisk przepływowych zachodzących podczas eksperymentów pomiarowych.

15

Numerical analysis of the selected air parameters in the industrial boiler plant

Cichowicz R., Stelęgowski A. W.

Acta Innovations

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2017

|

no. 23

51--61

EN

In every boiler plant, including industrial boiler plants of thermal capacity above 2 MW, substantial heat gains are generated during the work of combustion units. As a result, the indoor air temperature raises in the room, which affects thermal comfort of workers operating such technological installations. Therefore, heat removal requires an effective mechanical ventilation system. A numerical analysis of the selected air parameters in a room equipped with combustion devices was undertaken using computational fluid dynamic (CFD) simulations in the DesignBuilder software. This was done for a combustion plant in the “Installation of Thermal Treatment of Sewage Sludge” building, located in the “Group Sewage Treatment Plant” complex of Lodz, Poland. The numerical analysis was based on experimental measurements and the results concerning the personnel work area were compared to the guidelines of the ISO international standard 7730:2005.

16

Koncept ekologicznie przyjaznego masowca „Gary Muwalt” napędzanego siłą wiatru

Kozak J., Czaja A., Dąbrowski P.

Prace Wydziału Nawigacyjnego Akademii Morskiej w Gdyni

|

2016

|

Z. 31

94--103

PL

W artykule przeanalizowano możliwości, jakie niesie wykorzystanie siły wiatru we współczesnym transporcie morskim na przykładzie ekologicznego masowca z napędem żaglowym. W tym celu dokonano analiz oporowych przy użyciu metod CFD oraz analizy ekonomicznej na podstawie danych rynkowych. Jest to wstęp do dalszych prac, mających na celu stworzenie nowoczesnej jednostki ograniczającej emisję szkodliwych substancji do atmosfery oraz pozwalającej armatorom obniżyć koszty transportu ze względu na niższe zużycie paliwa. Projekt został wykonany przez Koło Naukowe CAD/CAE Studentów PG "PIKSEL", działające na Wydziale Oceanotechniki i Okrętownictwa Politechniki Gdańskiej.

EN

This paper analyzes the concept of ecological bulk carrier with sail propulsion for the opportunities offered by the use of wind in the modern maritime transportation. For this purpose, the analysis was made by using CFD methods and economic on the basis of market data. This is an introduction to further work aimed at creating a modern unit limiting the emission of harmful substances into the atmosphere and allows ship owners to reduce transport costs due to lower fuel consumption. The project was made by the GUT Student's CAD/CAE Research Club, acting at the Faculty of Ocean Engineering and Ship Technology Gdańsk University of Technology.

17

Velocity and temperature field inside a passive solar air collector. Preliminary results of CFD analysis

Fiuk J., Dutkowski K.

Polska Energetyka Słoneczna

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2016

|

nr 1-4

27--31

EN

This paper presents preliminary results of a CFD analysis of passive solar air collector. The geometry used in simulation is a representation of a prototype solar air collector which has been investigated experimentally in laboratory of Heat Engineering and Refrigeration Department of Koszalin University of Technology. The external dimensions of collector are 2 x 1 m (heigth x width). The absorber plate is flat. The set of experimental results is used in validation the numerical approximations of the flow field. Most notably, the mean velocity at inlet and temperatures can be easily compared between these two data sets, leading to a comprehensive conclusions. The numerical results are in agreement with experiment. The results revealed a behavior of fluid in the discussed geometry that promotes backflows and may be the cause of momentum loss.

18

Investigation on Aerodynamics of Super–Effective Car for Drag Reduction

Cieśliński A., Prym W., Stajuda M., Witkowski D.

Mechanics and Mechanical Engineering

|

2016

|

Vol. 20, nr 3

295--308

EN

This paper focuses on shape optimization of a car body to be used in Shell Eco Marathon race. The work consists of the review of aerodynamic performance for currently used shapes, definition of the design constraints for the vehicle and recommendations for the final shape to be used in the oncoming Shell Eco Marathon editions. The designs are inspired by winning models, but adjusted to Iron Warriors technology and scaled accordingly to the driver’s space requirements. A range of velocities from 20 km/h to 45 km/h with 5 km/h interval is tested, giving idea about the full model performance. Results are then compared and the best solutions, concerning the coefficient and parameter taking into account the frontal area influence are recommended.

19

Investigation of the side wind effects on the passenger ferry in rolling motion conditions

Jurczak W., Kaup M., Kaup J.

Journal of KONES

|

2016

|

Vol. 23, No. 3

241--248

EN

The article presents the investigation results of selected effects of the side wind on the passenger ferry in sea condition. The computational fluid dynamic (CFD) analysis has been carried out in order to calculate the forces and moments acting on the ship superstructure during rolling caused by waves. The performed analysis shows the impact of rolling amplitudes and periods on results. The use of CFD method allows calculating the vertical centre of pressure with various rolling parameters. Numerical analysis has been performed for real size ship model in transient condition. The main object of the research is to define the influence of the wind dumping effect on wave rolling motions. Additional wind dumping effect (besides of other effects) is intending to use in response amplitude operator (RAO) calculations (next part of researches). It is possible that use of additional wind dumping effect will reduce the rolling amplitudes, and consequently reduce ship accelerations due to rolling motions. Reduction of accelerations (especially horizontal), should decrease the requirements due to number of cargo lashes/belts equipment and minimize the lashing time. From other side it should shorten required harbour time and reduce the ship speed, what is the best way to save the fuel.

20

Analiza CFD przepływu polimeru w dwustożkowej uplastyczniająco-homogenizującej strefie wytłaczarki ślimakowo-tarczowej

Michalska-Pożoga I., Jakubowski M.

Przemysł Chemiczny

|

2015

|

T. 94, nr 12

2105-2111

PL

Przedstawiono model oryginalnej wytłaczarki charakteryzującej się występowaniem dwustożkowej strefy tarczowej. Opisywana konstrukcja jest odmianą wytłaczarki ślimakowo-tarczowej z jednostożkową strefą tarczową. Eksperymentalnie potwierdzono niewielkie oddziaływanie jednostożkowej strefy tarczowej na budowę i właściwości tworzyw. Zmiana konstrukcji strefy tarczowej wytłaczarki ślimakowo-tarczowej dzięki zastosowaniu stożków o dwóch różnych kątach pochylenia i zwiększeniu powierzchni tarcz, pozwoliło na intensywniejsze oddziaływanie charakteru i parametrów przepływu na budowę i właściwości polimeru. Na podstawie analizy numerycznej wyznaczono charakter ruchu cząsteczek polimeru wraz z wartościami prędkości, minimalne i maksymalne wartości szybkości ścinania, a także mapy wektorowe prędkości w dwustożkowej strefie uplastyczniająco-homogenizującej wytłaczarki ślimakowo-tarczowej. Ponadto określono zmianę ruchu cząsteczek i charakteru przepływu w zależności od szerokości szczeliny tarczowej i prędkości kątowej. Dokonano porównania między wartościami prędkości przepływu, szybkości ścinania i naprężeń ścinających uzyskanych w jednostożkowej i dwustożkowej strefie tarczowej. Symulacja została wykonana dla polietylen małej gęstości. Do analiz numerycznych zastosowano program Ansys CFX 12.1.

EN

Extrusion of low-d. polyethylene (PE-LD) in innovative extruder with double-cone disc zone was modelled to det. the characteristics of the PE-LD particles motion along with their velocity values, as well as min. and max. rates of shear and to generate vector maps of velocity inside the extruder in relation to the crevice between the disc width and the angular velocity. A comparison was made between the flow velocity, a shear rate and shear stress in singlecone and double-cone zones. The numerical simulation was performed by using a com. software program.