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Numerical Simulation of Erosion on Aluminium Plate with a Cylindrical Hole

Hadžiahmetović Halima, Džaferović Ejub, Midžić Kurtagić Sanda, Blažević Rejhana

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 2

61--70

EN

The purpose of the present study is to simulate erosion on the aluminium plate with a cylindrical hole caused by solid particles after passing through 90° elbow, using the Computational Fluid Dynamics (CFD), the Discrete Phase Model (DPM), and erosion equations. Discrete trajectories of solid particles are calculated using the Lagrangian approach, while the simulation of the fluid was obtained by solving the fluid motion equation using the Eulerian approach. Supplementary sub-models are incorporated into the software to enhance the accuracy of particle trajectory calculations within the simulated geometry. These sub-models include collisions of solid particles with walls (stochastic model) and erosion model. The numerical simulation results obtained in this paper were compared with the existing experimental results from the group of authors, demonstrating a good match. The paper provides the main characteristics of the mathematical model, along with the interpretation of results and a discussion, with the key findings highlighted in the conclusion. The findings indicate that erosion process is significantly influenced by both the particle impact velocity and impact angle, which are key parameters in many erosion equations. Furthermore, it is observed that the velocity of the particles is consistently lower than the mean velocity of the air. Additionally, the angle at which the particles impact the aluminium plate is not always exactly 90° due to multiple collisions with the wall, signifying that the particles do not move exclusively vertically.

2

Frictional Aspects of Operation for Centrifugal Accelerators with Radial Blades

Krupicz Bazyli, Barsukov Vladimir G., Ilkevich Maria A.

Tribologia

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2022

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nr 3

39--48

EN

The work aims to determine the friction effect and change the velocity and kinetic energy during the movement of solid particles along the rotating machine's radial blade surface. It has been previously shown that the influence of the frictional forces of the particle against the rotor disc is negligible compared to the influence of the centrifugal force and the friction force of the particle against the rotor blade. Based on the analysis of the differential equation solution for particle motion along the surface of the blades, it was established that the total sliding velocity of a particle increase intensively in the initial period of motion and approaches asymptotically to the values described by a linear function, practically independent of the initial position of the particle. The obtained analytical expressions enable the determination of change in the relative and total velocity of the particle, the angle between the respective velocity vectors and its kinetic energy. Changes in the values of these parameters were also estimated for a wide range of variability of the friction coefficient.

PL

Celem pracy jest określenie wpływu tarcia cząstek stałych na ich prędkość i straty energii kinetycznej podczas ruchu po powierzchni łopatek promieniowych maszyn wirnikowych. Wykazano, że wpływ sił tarcia cząstki o tarczę wirnika jest pomijalnie mały w porównaniu z wpływem siły odśrodkowej i siły tarcia cząstki o łopatkę wirnika. Na podstawie analizy rozwiązania równania różniczkowego ruchu cząstek po powierzchni łopatek ustalono, że całkowita prędkość poślizgu cząstki intensywnie wzrasta w początkowym okresie ruchu i zbliża się asymptotycznie do wartości opisanych funkcją liniową, praktycznie niezależną od położenia początkowego cząstki. Uzyskane wyrażenia analityczne umożliwiają określenie: zmiany prędkości względnej i całkowitej cząstki, kąta pomiędzy odpowiednimi wektorami prędkości oraz jej energii kinetycznej. Dokonano również oszacowania zmiany wartości tych parametrów dla szerokiego zakresu zmienności współczynnika tarcia.

3

Solid particle erosion in the sudden contraction of raw water pipeline

Amori Karima E., Al-Salmany Zaid

Diagnostyka

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2022

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Vol. 23, No. 1

art. no. 2022110

EN

The steady 3-D raw water turbulent flow is numerically investigated. This flow is formed of solid silica sand (quartz) carried by water in stainless steel pipe. The flow in a straight pipe and flow in a pipe with a sudden contraction are analyzed using a two-way coupled Eulerian-Lagrangian approach. Erosion rate is estimated by Oka erosion model combined with the constant coefficient of restitution. The effect of solid particles mass flow rate, inlet velocity, particle diameter, internal pipe diameter, orientation, contraction coefficient, and wall pipe contraction angle on erosion rate are examined. The predicted erosion is distributed homogenously for straight pipe, while the step wall area of the contraction is the most eroded part. The erosion rate increases with the increase of solid particles diameter, flow rate, inlet velocity, and decreasing pipe diameter. Iit is found that the erosion is limited till the particle diameter reaches 500 µm then it starts to increase. The erosion rate increases with decreasing contraction coefficient and step wall angle. When the step wall angle decreased to 300, the erosion rate is reduced by 30 times that for 900. So, decreasing step wall angle can be considered as a geometrical solution to reduce erosion rate.

4

Numerical Analysis of Solid Particles Flow in Liquid Metal

Szucki M., Goraj T., Lelito J., Suchy J. S.

Archives of Foundry Engineering

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2013

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Vol. 13, iss. 3 spec.

161--166

EN

The aim of the study was to determine the influence of the solid particles density and size on their distribution in the solidified cast. As part of the work, a series of numerical simulations of filling and solidification process were made with the use of FLOW-3D software. The analysis was performed on pure aluminum and six chosen types of particles with different size and density. Obtained results may help to understand the behavior of solid particles in liquid metals.

5

Rzutowe współczynniki wypukłości cząstki ciała stałego

Sulkowski A.

Zeszyty Naukowe. Inżynieria Chemiczna i Procesowa / Politechnika Łódzka

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2000

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Z. 28

181-188

PL

W pracy sformułowano matematyczne podstawy metody opisu struktury powierzchni cząstki ciała stałego w oparciu o analizę cech geometrycznych jej dwuwymiarowych projekcji ortogonalnych na ustaloną płaszczyznę ekranu. Podstawę proponowanej metody stanowi koncepcja opisu odchylenia kształtu cząstki od wzorca, za który przyjęto wypukłość zbioru. Przedstawiono konstrukcję geometrycznego modelu przestrzeni kierunków obserwacji cząstki. Sformułowana została ogólna definicja współczynnika kształtu. Zdefiniowano projekcyjne współczynniki wypukłości i erozji cząstki oraz opisano ich właściwości. Wyznaczono analityczną postać rozważanych współczynników dla wybranych modeli cząstek niewypukłych.

EN

Mathematical foundations of solid particle shape description method were established. Particle was assumed to be joint and compact subset of three dimensional real space. Geometrical model of projection directions space was proposed. General definition of shape parameter was introduced. Particle convexity and erosion factors were defined. Main properties of factors introduced were discussed. Mathematical formulae and graphical representation of projective convexity and erosion factors, for some geometrical concave particle models, were derived.