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Calculation of Hydrodynamic Characteristics of Apparatus with Regular Tubular Packing

Issayeva Aikerim Nurlankyzy, Korganbayev Bayrzhan Nogaybaevich, Volnenko Alexandr Anatolevich, Zhumadullayev Daulet Koshkarovich, Jumadillayeva Gulzhamal Nurtazaevna

Rocznik Ochrona Środowiska

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2021

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Tom 23

868--882

EN

Among the apparatuses with a regular arrangement of packing elements creating an in-phase mode of vortex interaction, which ensures high efficiency of the processes, it is interesting to use a standard tubular packing. Such packing allows additional advantages associated with heat supply or extraction directly in the contact zone of the interacting phases, which is very important for conducting some chemisorption processes. The research covers such hydrodynamic regularities as hydraulic resistance during a heat carrier movement in pipes and during external flow around a tubular beam, retained liquid amount and gas content of layer in the external flow around the tubular beam with liquid and gas flows. The research was carried out using an experimental setup with a heat and mass transfer apparatus with regular tubular packing. The medium used during experiments is water-air. The research methodology included standard methods for determining hydraulic resistance and retained liquid amount and visual observation and photographing of gas-liquid flows. The novelty of the research was equations – one for calculating the hydraulic resistance in pipes, taking into account local resistances and pipe roughness. The other ones for determining the pressure losses during the external flow around the tubular beam, the retained liquid amount, and the gas content of the layer, taking into account the vortex interaction of gas and liquid flows. Graphical and calculated dependences of the investigated hydrodynamic characteristics were obtained as a result of the conducted research of the hydraulic resistance during the heat carrier movement in the pipes, as well as the hydraulic resistance and the retained liquid amount during the external flow around the tubular beam with a change in the gas velocity and irrigation density. When the heat carrier flows in the pipes, the numerical values of the hydraulic resistance in the transient mode do not exceed 1.5 kPa, in the developed turbulence mode in the range of the Reynolds number from 1·104 to 6·104 ΔР varies from 1.5 to 53 kPa. With the external flow around the tubular beam, in the developed turbulence mode wg=4 m/s and L = 25 m3/m2h, the hydraulic resistance is 85 Pa, the retained liquid amount is 4.5·10-3 m. The change in the irrigation density in this mode (developed turbulence) in the L range from 10 to 100 m3/m2h leads to an increase in the hydraulic resistance from 65 to 160 Pa, the retained liquid amount from 2.16·10-3 to 13.6·10-3 m. The calculated dependencies are the basis of the method for calculating the hydrodynamic characteristics of the apparatus with the regular tubular packing, which can be used to calculate industrial devices.

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The influence of remelting on the properties of AlSi6Cu4 alloy modified by antimony

Medlen D., Bolibruchova D.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 1

81-86

EN

The paper deals with the problem of multiple remelting influence on AlSi6Cu4 alloy modified by antimony on chosen mechanical characteristics, microstructure and gas content. This foundry alloy is used mostly in automotive industry. Foundry Aluminum-Silicon alloys are also used in number of industrial weight sensitive applications because of their low weight and very good castability and good mechanical properties. Modifiers are usually added to molten aluminum-silicon alloys to refine the eutectic phase particle shape and improve the mechanical properties of the final cast products and Al-Si alloys cast properties.

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Influence of antimony on the mechanical properties and gas content of alloy AlSi6Cu4

Medlen D., Bolibruchova D.

Archives of Foundry Engineering

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2011

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Vol. 11, iss. 1

73-78

EN

Aluminium alloys based on Al-Si are used in automotive and aerospace industries. AlSi6Cu4 alloy is used the complicated castings, which must comply high strength requirements. Strength characteristics can also be affected by the modifiers: Na, Sr, Sb. In the literature is mentioned, that AlSi6Cu4 modified by sodium and strontium has negative effect - increases of the gas absorption. Modification of AlSi6Cu4 alloy by antimony, is still not mentioned in the literature. The article gives the effect of antimony on selected mechanical properties and gas content of foundry alloy AlSi6Cu4.

4

Określenie zawartości gazów w metalu wytapianym w piecu obrotowym w różnych etapach cyklu technologicznego wytwarzania odlewów rur z żeliwa sferoidalnego

Pytel A., Turzyński J., Węgrzyn W.

Biuletyn Instytutu Odlewnictwa

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2002

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R. 4, nr 2

3-11

PL

Wprowadzenie technologii spalania gazu w wydajnych i ekonomicznych palnikach gazowo-tlenowych spowodowało znaczny wzrost zastosowania pieców obrotowych w odlewniach. Proces topienia żeliwa w piecu obrotowym z palnikiem gazowo-tlenowym typu "Aljet" jest procesem stosowanym dopiero w ostatnich latach, stąd też uważano za celowe przeprowadzenie badań przemysłowych, mających na celu określenie poziomu zawartości gazów (tlenu, wodoru, azotu) w żeliwie w stanie ciekłym i stałym, w różnych stadiach przygotowania metalu do produkcji rur z żeliwa sferoidalnego. W artykule omówiono nowoczesne urządzenia do pomiaru aktywności tlenu (Multi-Lab Celox Foundry) i wodoru (Multi-Lab Hydris) w ciekłym żeliwie oraz przedstawiono zasadę pomiaru aktywności tlenu i zawartości wodoru. Za pomocą nowoczesnych urządzeń przeprowadzono szereg pomiarów zawartości gazów w ciekłym żeliwie w warunkach produkcyjnych, jak również w żeliwie w stanie stałym. Zakres badań obejmuje wykonanie pomiarów zawartości gazów w różnych etapach procesu produkcyjnego wytwarzania żeliwa sferoidalnego, wytapianego w piecu obrotowym. Pomiary wykonano w piecu obrotowym, piecu indukcyjnym, w żeliwie w kadzi po zabiegu sferoidyzacji i modyfikowaniu w zbiorniku zalewowym przed odlewaniem rur, jak również w ściankach rur.

EN

Introducing the technology of gas after-burning in highly-effective and cost-saving gas-oxygen burners considerably increased the use of rotary furnaces in foundry plants. The process of melting cast iron in a rotary furnace provided with gas-oxygen burner of an "Aljet" type has been used only recently, and therefore it has been considered advisable to carry out tests in industrial plants to determine the level of gas content (oxygen, hydrogen, and nitrogen) in cast iron in both liquid and solid state at different stages of metal treatment for the production of pipes in spheroidal graphite cast iron. The article describes modern equipment used for the measurement of oxygen and hydrogen activity (Multi-Lab Celox Foundry and Multi-Lab Hydris, respectively) in liquid cast iron. The principle of oxygen activity and hydrogen content measurement has been presented. Using modern equipment, a number of measurements have been taken to establish gas content in both molten and solid cast iron under production conditions. The range of measurements covered gas content determination at different stages of the process of manufacturing spheroidal graphite cast iron melted in rotary furnace. Measurements were taken in rotary furnace, in induction furnace, in a ladle on cast iron after the spheroidising and inoculation treatment, in stationary "buckets" before casting of pipes, and also in the pipe walls.