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Numerical Modeling of Wall Pressure in Silo with and Without Insert

Askif Frzat, Hammadeh Hala, Ubysz Andrzej, Maj Marek

Studia Geotechnica et Mechanica

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2021

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Vol. 43, nr 1

22--33

EN

This paper presents a methodology based on the finite element method to simulate the flow of granular materials. Moreover, it allows proper estimation of dynamic pressure during silo discharge since this subject is still under discussion, especially for designing silos with an insert (an input element). A 2-D simulation of the discharge process of a cylindrical silo with cone and a central discharging orifice was performed. Two cases were studied, with and without using insert in silo. Numerical analysis was carried out with the help of the uncoupled arbitrary Lagrangian–Eulerian (ALE) approach. The resulting dynamic pressure distribution on the silo wall for each of the two cases was inferred numerically. The resulting values of pressure were compared with the results of the experimental study on a cylindrical metal silo to demonstrate the accuracy of the numerical model in determining the dynamic wall pressure, especially in the case of using an insert in silo during discharge.

2

Effect of using insert on the flow pressure in cylindrical silo

Hammadeh Hala, Askifi Farzat, Ubysz Andrzej, Maj Marek, Zeno Amjad

Studia Geotechnica et Mechanica

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2019

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Vol. 41, nr 4

177--183

EN

This paper presents an experimental investigation of the discharge flow pressure in the vertical silo and the hopper due to the use of insert (top cone with trunk cone bottom). Using the Insert inside the silos is one of the proposed solutions to avoid the problems of having funnel flow pattern, which has a significant effect on the distribution of flow pressure exerted on the silo wall and the hopper. The experiments were performed on a metal cylinder prototype; corn was used as a granular material, and the wall and hopper pressure distribution was measured by a special pressure transducer. The experiments revealed an important result in the flow pressure due to the change in the location of the insert. The experiments were conducted in Damascus University laboratories.

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Interpretacja danych ciśnieniowych początkowego okresu przypływu płynu do otworu, przechodzącego przez warstwę produktywną ze szczeliną poziomą

Szpunar T., Budak P.

Nafta-Gaz

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2009

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R. 65, nr 9

686--691

PL

W artykule podano proste zależności umożliwiające interpretację danych ciśnieniowych początkowego okresu przypływu płynu złożowego do otworu z warstwy ze szczeliną poziomą, umożliwiające określenie przepuszczalności lub pola powierzchni szczeliny.

EN

Provided are relations which describe the early time flow pressure behavior in wells with horizontal fracture. Derived relations allows us to compute permeability or surface area of a horizontal fracture.

4

Straty ciśnienia przy przepływie mieszaniny gazowo - cieczowej w U-rurach

Pietrzak M., Witczak S.

Systems : journal of transdisciplinary systems science

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2008

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Vol. 13, spec. iss. 2/2

84--90

EN

This paper presents results of investigations relative of values of two-phase air-oil and air-water flow press losses. The investigations were conducted in horizontal U-pipe bend with the internal diameter 0.016 curvature radius 0.11 m and angle 180°. The machine oil Itherm 12 was used as the working fluid. The viscosity and density of oil were changed in range: ηa- (0.091-0.528) Pa s and Q0- (869.6-884.5) kg m-3. The range of superficial velocity of air νa,0 = (0.37-2.89) m s-1, of oil ,.ν0 = (0.014-O.047) m s- 1 and of water ν r0) - (0.035-0.25) m sA new correlation for two-phase flow pressure drop in 180° pipe bend is propc based a total of 124 experimental data points for air-oil and air-water flow. The correlation predicts all with a coefficient correlation R=0.972 and 82 % of the data fall within ± 30 % error bands.

5

Study on the surface generation mechanism in machining

Kobayashi A, Mizutani T., Kurata Y.

Applied Mechanics and Engineering

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1999

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Vol. 4, no spec.

285-290

EN

Surface generation mechanism by the burnishing action in machining has been examined experimentally under various velocity and load conditions. The surface generation characteristics are estimated by the surface improvement ratio ( the ratio of the deformed asperity heights and the original heights ) and the plastic flow pressure, Pm, based on the junction growth theory of Tabor (1959). Burnishing velocity in this study's region does not influence the friction coefficient (the ratio of burnishing load and friction force). The tip of asperity deformed plastically by burnishing action mainly flows in both sides of the asperity.