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The study on the influence of the injected flow swirling on the characteristics of the jet pump

Panevnyk D. O.

Journal of Achievements in Materials and Manufacturing Engineering

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2022

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Vol. 113, nr 1

22--30

EN

Purpose: of this paper is to analyze the possibility of increasing the efficiency of wellbore jet pumps by twisting the injected flow. The absence of moving parts, easy transfer of energy, the ability to operate a wide range of performance and low cost have resulted in the use of ejection systems in many oil and gas deposits. The main disadvantage of borehole ejection systems is the insufficient value of the jet pump efficiency. The energy efficiency of downhole jet pumps can be improved by swirling the mixed flows. Design/methodology/approach: To characterize the effect of circulating flows was used an additional factor in the form of the values of the inclination angle of guiding elements that swirl the flow or the rotation frequency of jet pump elements. In the process of determining the values characterizing the operating process of ejection systems, the flow rates of the working and injected flow and the pressure values in front of the nozzle, the receiving chamber and the chamber at the outlet from the diffuser of the jet pump are subject to direct measurement. Swirling of the injected flow was carried out by placing a sleeve with guiding elements, manufactured using 3D printing technology, in the receiving chamber of the jet pump. Findings: The analysis revealed that in the design of downhole jet units, there are used guiding elements, mainly the screw, blade and tangential type, to swirl the flow. A highlighted list of factors that have a direct effect on the flows mixing process. During experimental studies of swirling injected flow type jet pump characteristics, there is obtained an increase in pressure and energy parameters. Research limitations/implications: The task of further research is to determine the characteristics of a downhole swirling injected flow type jet pump for conditions of combined swirling of the working and injected flows. Practical implications: The obtained results make it possible to take into account the presence of guiding elements in the flow path of the jet pump for swirling the flow. Originality/value: It is established that the relationship between the design and technological parameters of the local swirling of the mixed medium is determined by the ratio of rotating and axial components of the flow velocity in the flow path of the jet pump.

2

Hot Layer Formation during the Crude Oil Fires

Jarosz W., Stawczyk J.

Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej

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2016

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Nr 58 (tom 1) (2)

5--16

EN

The paper presents the research results on hot layer formation during the crude oil fires, the conditions for creating a hot layer, mechanisms of the boilover and its accompanying dangerous phenomena. The research was carried out in The Main School of Fire Service in Warsaw. In the experiments, crude oil was burned in tanks with the diameter of 1.4 m and two different heights – 0.7 and 1.4 m.

PL

W artykule przedstawiono wyniki badań nad formowaniem się warstwy gorącej, warunków tworzenia się warstwy gorącej, mechanizmu wyrzutu i zjawisk towarzyszących podczas pożarów ropy naftowej, które zostały przeprowadzone w Szkole Głównej Służby Pożarniczej w Warszawie. W eksperymentach spalano ropę naftową w zbiornikach o średnicy 1,4 m i dwóch różnych wysokościach – 0,7 i 1,4 m.

3

Boilover and slopover phenomena during a fire of storage tanks containing crude oil

Jarosz W.

Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej

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2011

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Nr 42

15--22

EN

The most interesting research regarding burning fuel tankers has been the work of Blinov and Khudiakov [3], who first described the formation of overheated layer in the liquid during the fire and the way of its moving into the fuel. This work of Blinov and Khudiakov has begun the research process on overheated layer and its impact on the speed of slopover and boilover. Currently, the most interesting works are carried in research centers of Japan, USA and Germany and they concentrate on: • a fuel burning rate, • a way of heat transfer from the flame to the surface of a burned liquid, • a flame height, • an over he a ting mo del, • slopover and boilover models, • distribution of temperature in liquid during tank fire.

4

Struktury odmienione węgla kamiennego w strefach zaburzeń tektonicznych – propozycja klasyfikacji

Godyń K.

Prace Instytutu Mechaniki Górotworu PAN

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2011

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Vol. 13, no. 1-4

11--29

PL

W kopalniach węgla kamiennego, w bezpośrednim sąsiedztwie uskoków występują strefy silnie narażone na zaistnienie niekontrolowanych zjawisk gazogeodynamicznych. Jest to spowodowane specyficzną, odmienioną budową wewnętrzną węgla znajdującego się w strefie zaburzonej tektonicznie – przyuskokowej. W pracy dokonano szczegółowego opisu tych wewnętrznych zaburzeń strukturalnych w węglu, rodzaju i stopnia tych zmian. Do badań wykorzystano metody: mikroskopii w świetle spolaryzowanym, odbitym oraz skaningowej mikroskopii elektronowej (SEM EDX). Dokonano również pomiarów mikrotwardości węgla w różnym stadium degradacji struktury wewnętrznej. Do tego celu posłużono się mikrotwardościomierzem wykonującym pomiary twardości metodą Vickersa. Na podstawie tych badań dokonano ujednolicenia klasyfikacji takiego „odmienionego strukturalnie” węgla a także określono jego podatność na możliwość inicjacji wyrzutów w kopalniach węgla kamiennego.

EN

In hard coal mines, in the direct vicinity of faults, there exist areas particularly prone to occurrence of uncontrollable gas-geodynamic events. The existence of these areas is due to a specific, nonstandard internal structure of coals present in a tectonically disturbed (i.e., near-fault) zone. The paper provides a detailed description of these internal distortions in coal, as well as of the type and degree of these alterations. For the purpose of the research, the following methods were used: polarized light microscopy, reflected light microscopy, and scanning electrone microscopy (SEM) with an EDX adapter. Also, measurements of microhardness of coal were performed, for various stages of its internal structure damage. To this end, a microhardness tester making use of the Vickers method was applied. The results of the studies served as a basis for standardizing “structurally altered” coals, and helped to determine their susceptibility to a possibility of outburst initiation in hard coal mines.