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1

Innowacyjna metoda ciągłego pomiaru odkształceń ściany osłonowej aluminiowo-szklanej oraz opracowanie doświadczalno-numerycznej metody analizy stanu naprężeń w konstrukcji

Rusin Dawid, Juraszek Janusz

Przegląd Budowlany

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2024

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R. 95, nr 3

30--33

PL

W artykule przedstawiono nowatorską metodologię badań oraz monitoringu fasad aluminiowych z wykorzystaniem światłowodowych czujników odkształceń FBG (Fiber Bragg Grating) w budynkach wysokościowych HRB (High-Rise Building). Celem jest wyznaczenie rzeczywistego oddziaływania wiatru na te konstrukcje. Zaproponowane rozwiązania pozwalają na dokładniejsze i bardziej szczegółowe pomiary odkształceń i ugięć niż tradycyjne. Umożliwiają ich monitorowanie nieprzerwanie w długim czasie – dzięki temu możliwe będzie optymalizowanie konstrukcji fasady pod kątem bezpieczeństwa i wpływu na środowisko, a także sprawdzenia jej stanu technicznego. Metoda ta zostanie zastosowana do badań fasady elementowej MB-SE65 firmy Aluprof S.A. Wyniki badań i analiz umożliwią opracowanie nowych wytycznych projektowania fasad aluminiowych. Przedstawiona metodologia ma duży potencjał i może być wykorzystana do badań innych typów konstrukcji aluminiowych.

EN

The article presents a novel methodology for research and monitoring of aluminium facades using FBG (Fiber Bragg Grating) optical strain sensors in high-rise buildings (HRB). The aim is to determine the real impact of wind on these structures. The proposed solutions allow for more accurate and detailed measurements of deformations and deflections than traditional methods. They enable continuous monitoring over long periods of time. This will allow for the optimization of facade design in terms of safety and environmental impact, as well as to verify its technical condition. The method will be applied to the research of the MB-SE65 element facade by Aluprof S.A. The results of the research and analysis will allow for the development of new guidelines for the design of aluminium facades. The presented methodology has a high potential and can be used for research on other types of aluminium structures.

2

Numerical simulation of the influencing factors of array jet shock cooling

Zhou Nianyong, Zhou Youxin, Zhao Yingjie, Bao Qingguo, Tang Guanghua, Lv Wenyu

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 4

art. no. e150200

EN

Array jet impingement cooling is a significant technology of enhanced heat dissipation which is fit for high heat flux flow with large area. It is gradually applied to the cooling of electronic devices. However, The research on the nozzle array mode and the uniformity of the cooling surface still has deficiencies. Therefore, the influence of heat flux, inlet temperature, jet height, array mode, and diversion structure on jet impingement cooling performance and temperature distribution uniformity is analyzed through numerical calculation. The results show that the heat transfer coefficient of jet impingement cooling increases linearly with the increment of heat flux and inlet temperature. With the increment of the ratio of jet height to nozzle diameter (H/d), the heat transfer coefficient increases first and then decreases, that is, there is an optimal H/d, which makes the heat transfer performance of the array jet impact cooling best. The temperature uniformity of array jet impact cooling is greatly affected by array mode. The improvement effect of nozzle array mode on temperature uniformity is ranked as sequential >staggered >shield >elliptical array. The overall temperature uniformity and heat transfer coefficient are increased by 5.88% and 7.29% compared with the elliptical array. The heat transfer performance can be further improved by adding a flow channel to the in-line array layout, in which the heat transfer coefficient is increased by 6.53% and the overall temperature uniformity is increased by 1.45%.

3

A pre-protection method for a pipe-jacking channel over shield tunnels

Cui Yunliang, Yang Xukun, Wang Xinquan, Diao Hongguo, Li Xiao, Gao Yuanyuan

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 2

art. no. e148443

EN

With the improvement of the planning level of underground space, the location of the planned under-crossing tunnel can be known in advance when constructing the upper-span tunnel. Therefore, pre-protection measures can be taken in advance during the construction of the upper-span tunnel. A new pre-protection method of a pipe-jacking channel was proposed to reduce the adverse effects of under-crossing shield tunnels. Numerical simulations of different pre-protection schemes were carried out using the finite element method to analyze its deformation control effect. The simulation results show that the deformation control effect of the gantry reinforcement scheme is the most significant. It is shown that the displacement of the pipe-jacking channel is more significantly suppressed with pre-protection measures than without preventive protection measures. The vertical displacement curve of the pipe-jacking channel exhibits a “W” shape after the construction of the double-lane shield underpass. By comparing the three different working conditions, it is found that the maximum vertical displacement and surface settlement of the pipe-jacking channel greatly reduced the gantry reinforcement pre-protection. Compared with Case 3, the effect of the pre-protection measures adopted in Case 2 was less obvious, which indicated that the form of the pre-protection had an important influence on controlling the deformation of the pipe-jacking channel.

4

Effect of surface energy on the contamination characteristics of porcelain double umbrella insulators

Lv Yukun, Wang Qian, Chen Zeze

Archives of Electrical Engineering

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2024

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Vol. 73, nr 1

235--250

EN

To explore the influence of surface energy on the contamination characteristics of insulators, COMSOL Multiphysics software was used to simulate the contamination characteristics of XWP 2 -160 insulators under wind tunnel conditions, and the rationality of the modified expression of the dynamic deposition model of the contaminated particles was verified. The change of contamination characteristics before and after changing the surface energy of insulators under natural conditions was simulated and analyzed. The results show that under the original surface energy (72 mJ/m2 ) and low surface energy (6.7 mJ/m2) with the increase in particle size, the contamination amount of an insulator surface area decreases first and then increases. When the wind speed is 2 m/s, the change in the particle size has the most pronounced effect on the amount of contamination. The amounts of contamination for the low surface energy are 64–75%, 60–95%, 55–91% and 54–78% lower than those for the original surface energy for particle sizes of 10, 15, 20 and 25 µm, respectively. For the same wind speed, when the size of contamination particles increases, the difference between the ratio of DC and AC contamination accumulation is gradually increasing because of the influence of the electric field force. From the perspective of the insulator preparation process, the development of low surface energy insulators can improve their anti-fouling performance.

5

Study on failure modes and calculation method of the cast steel joint with branches in treelike structure

Chen Feng, Sun Yun, Sun Shuxuan, Song Da, Liu Yangbing

Archives of Civil Engineering

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2024

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Vol. 70, nr 1

589--604

EN

The treelike structure links members and transfers loads via its solitary cast steel joint with branches. Therefore, the joint’s bearing capacity significantly affects the treelike structure’s stability, security, and economics. This paper utilized experimental verification and numerical modeling to examine the mechanical behavior of cast-steel joints with branches in the treelike structure under various loading conditions. Then, researchers investigated the failure process and mechanism of joints, and the three most common failure modes were outlined. Furthermore, the researchers proposed the bearing capacity calculation formula based on the common failure modes. The results show that the three common failure modes of the cast-steel joints with branches under different loading conditions are the failure in the joint core area under the axial load, the failure in the main pipe compression side under eccentric load, and the failure in the compression side of the single branch pipe root when the single branch pipe is under the uneven load. The suggested empirical calculation method can serve as a reference point for similar engineering practices design.

6

Safety assessment of the construction of double track tunnels underneah exsiting railway tunnels

Guo Fengfeng, Chen Yupeng, Zhang Yongjie, Feng Qi, Cui Da

Archives of Civil Engineering

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2024

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Vol. 70, nr 1

375--387

EN

The ground disturbance caused by the tunnel construction will inevitably have an impact on the upper part of the constructed tunnel structure, and the railroad tunnel requires a very high level of control over the structural settlement deformation. For the problem of double-hole tunnel under the built tunnel, this paper takes Chongqing Mingyue Mountain Tunnel under the built Shanghai-Rong Railway Paihua Cave tunnel and Zheng-Yu Railway tunnel as the engineering background, and starts from the mechanism of ground loss caused by tunnel excavation, firstly, the settlement at the height of the existing tunnel strata is obtained through theoretical analysis, and the new Mingyue Mountain Tunnel under the Shanghai-Rong Railway tunnel is determined to be a more dangerous section. Further simulate and calculate the dynamic excavation process of the new double-hole tunnel underpass, and study the settlement deformation law of the Mingyue Mountain Tunnel underpassing the Hurong Railway Tunnel. According to the requirements of railroad tunnel for settlement deformation control, the new tunnel is determined to be constructed by step method to ensure the safety of railroad tunnel. The shortcomings of the theoretical calculation are analyzed to illustrate the important role of numerical simulation in the evaluation of tunnel underpass projects.

7

Ground settlement and estimation of maximum settlement value in adjacent foundation pit excavation

Wu Yan

Archives of Civil Engineering

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2024

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Vol. 70, nr 1

605--619

EN

The excavation of adjacent pits following the initial foundation pit excavation can significantly influence ground settlement. Using a foundation pit excavation project in Changzhou as a prototype, this study employed the numerical simulation method in conjunction with the HSS model to analyze the settlement deformation characteristics of the original excavation and compare them with the recorded monitoring values. In this study, the analysis focused on the ground settlement between two pits by varying the spacing between them at different excavation depths. The findings revealed that the ground settlement does not exhibit a significant increase when the new pit is excavated at a shallow depth. However, it rapidly increases when the excavation depth of the new pit surpasses that of the existing pit. Furthermore, an increase in the distance between the two pits causes the maximum settlement position to shift towards the edge of the new pit. The maximum ground settlement is found to have a linear relationship with both the maximum horizontal displacement of the two pits and the spacing between them.

8

Design and Optimization of Casting System for Integrated Longitudinal Beam and Tower Package Based on Al-Si Alloy

Heng Li, Nan Wang, Xingyu Teng, Zhen Chai, Xiaoyong Zhu, Yucheng Wu

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 3

111--122

EN

This study optimized the integrated die-casting of an aluminum alloy longitudinal beam and tower component using no heat-treated aluminum alloy. Leveraging material properties and part geometry, a pouring system was designed and refined through mold flow analysis. This optimized the velocity, temperature distribution, and air entrapment to reduce defects like shrinkage porosity. The optimized pouring parameters were 695 °C melt temperature, 210 °C initial mold temperature, and 4.9 m/s shot speed. This reduced shrinkage porosity by 10.4% versus the original design. Die-casting trials with the optimized pouring system produced defect-free castings. The critical load-bearing section of the die casting had a yield strength of 184 MPa and elongation of 10.9%, which can meet the production requirements. In summary, based on the optimization of pouring system by mold flow analysis, by developing the integrated die casting process for aluminum alloy. Not only the defects are eliminated, but also the castings with sufficient mechanical properties are produced.

9

A Study on the Channel and Gap Flow Simulation For Electrical Discharge Micro-Drilling of Inconel 718 Superalloy

Machno Magdalena, Trajer Marcin, Czeszkiewicz Adrian, Żurawka Paulina

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 2

159--176

EN

The process of electrical discharge micro-drilling (micro-EDD) of micro holes is used in the aviation, automotive and biomedical industries. In this process, an important issue affecting the stability and efficiency of the process is the flow of the working fluid through the tool electrode channel and the front and side gap areas. Because tool electrodes have diameters below 1 mm. Many factors present in the EDM-drillig process occurring on a micro scale mean that a full explanation of the phenomena affecting the process is limited. The solution is to analyze the phenomena in the process based on the results of numerical simulations, which are based on real measurements. The aim of this work is to analyze the flow of de-ionized water through a brass single-channel electrode with a channel diameter of 0.11 mm and a front and side gap. The liquid flow was analyzed for various variants (with and without cavitation, with added rotation of the tool electrode, with and without surface roughnes with material particles). In simulation, it is important to gradually increase the complexity of the model, starting with the simplest model and gradually adding further phenomena. Analysis of the simulation results showed a significant impact on the liquid flow of cavitation, as well as the presence of vortex gaps in some areas, which have a significant impact on the process of drilling micro holes.

10

Analiza nośności na ścinanie betonowych próbek zespolonych z wrębami w płaszczyźnie zespolenia

Sadowski Grzegorz, Wiliński Piotr, Halicka Anna

Przegląd Budowlany

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2023

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R. 94, nr 5-6

87--92

PL

W pracy przedstawiono badania próbek zespolonych z powierzchnią prefabrykatu z wrębami oraz referencyjnych elementów monolitycznych. Na podstawie wyników badań laboratoryjnych wykonano modele numeryczne, które posłużyły do analizy sposobu zniszczenia złącza. Przeprowadzono analizę porównawczą efektywności złącza badanych elementów z modelami numerycznymi oraz wynikami badań dostępnymi w literaturze. Badania i analizy wykazały, że zniszczenie złącza nastąpiło przez ścięcie wrębów, poprzedzone zerwaniem adhezji w styku. Nośność złącza uzależniona jest od geometrii próbek oraz sposobu ich obciążenia.

EN

The paper presents tests of composite specimens with the indented surface element and reference monolithic elements. Based on the results of laboratory tests, numerical models were made, which were used for further analysis of the interface cracking. A comparative analysis of the effectiveness of the notches of the tested elements with numerical models and the results of research available in the literature was carried out. Testing and analysis showed that the failure of the joint occurred by notch shear, preceded by adhesion rupture at the interface. The bearing capacity of interface between the concrete depends on the specimens’ geometry and the way they are loaded.

11

Wymiana ciepła w lufie armaty przeciwlotniczej w czasie strzelań amunicją ćwiczebną oraz bojową - porównanie wyników obliczeń

Koniorczyk Piotr, Zieliński Mateusz, Surma Zbigniew

Problemy Techniki Uzbrojenia

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2023

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R. 52, z. 165

23--39

PL

W pracy przedstawiono wyniki symulacji numerycznych wymiany ciepła w ściance lufy wykonanej ze stali 30HN2MFA ar-maty przeciwlotniczej kalibru 35 mm podczas strzelań amunicją bojową oraz ćwiczebną. Obliczenia wykonano dla pojedynczego strzału oraz sekwencji siedmiu strzałów dla dwóch rodzajów amunicji 35x228 mm: z pociskiem podkalibrowym FAPDS-T oraz z pociskiem ćwiczebnym TP-T. Lufę o długości 3150 mm podzielono na 6 stref i w każdej z nich obliczono temperaturę w funkcji czasu wzdłuż grubości ścianki lufy podczas strzelań. Wyniki porównano dla obu rodzajów amunicji.

EN

The paper presents results of numerical simulations of heat transfer in the 35 mm anti-aircraft gun barrel wall made of 30HN2MFA steel during firing with combat and practice ammunition. Calculations were made for a single shot and a sequence of seven shots for two types of ammunition 35x228 mm: with FAPDS-T projectile and TP-T practice projectile. The 3150 mm long barrel was divided into 6 zones and in each zone the temperature versus time was calculated along the barrel thickness during firing. The results were compared for both types of ammunition.

12

Selected Aspects of Heat Transfer Study in a Gun Barrel of an Anti-Aircraft Cannon

Zieliński Mateusz, Koniorczyk Piotr, Surma Zbigniew, Preiskorn Marek, Sienkiewicz Judyta

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa

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2023

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Vol. 14, Nr 2 (52)

73--86

EN

The paper presents the results of computer simulations of the transient heat flow in the barrel wall of a 35 mm caliber cannon for a single shot and a sequence of seven shots for a selected 30HN2MFA barrel steel. It was assumed that the inner surface of the barrel does not have a protective layer of chromium or nitride. When calculating heat transfer in a barrel, constant and temperature variable values of thermal conductivity, specific heat and density (in the range from RT (Room Temperature) up to 1000℃) in the 30HN2MFA steel were assumed. The test results were compared for both cases. A barrel with a total length of 3150 mm was divided into 6 zones (i = 1,…, 6) and in each of them, the heat flux density was calculated as a function of the time 𝑞̇𝑖(𝑡) on the inner surface of the barrel. In each zone, the heat transfer coefficient, as a function of the time hi(t) and bore gas temperature as a function of the time Tg(t) to the cannon barrel for given ammunition parameters, was developed. A calculating time equaling 100 ms per single shot was assumed. The results of the calculations were obtained using FEM implemented in COMSOL Multiphysics ver. 5.6 software.

PL

W pracy przedstawiono wyniki symulacji komputerowych nieustalonego przepływu ciepła w ścianie lufy armaty kalibru 35 mm dla pojedynczego strzału i sekwencji siedmiu strzałów dla wybranej stali lufowej 30HN2MFA. Założono, że wewnętrzna powierzchnia lufy nie posiada ochronnej warstwy chromu lub azotku. Przy obliczaniu wymiany ciepła w lufie przyjęto stałe oraz temperaturowo zmienne wartości przewodności cieplnej, ciepła właściwego i gęstości (w zakresie od temperatury pokojowej (Room Temperature) do 1000℃) dla stali 30HN2MFA. Wyniki badań porównano dla obu przypadków. Lufa o łącznej długości 3150 mm została podzielona na 6 stref (i=1,…,6) i w każdej z nich obliczono gęstość strumienia ciepła w funkcji czasu 𝑞̇𝑖(𝑡) na wewnętrznej powierzchni lufy. W każdej strefie obliczono współczynnik przejmowania ciepła w funkcji czasu ℎ𝑖 (𝑡) oraz temperatury gazów prochowych w funkcji czasu 𝑇𝑔(𝑡) w lufie armaty dla zadanych parametrów amunicji. Dla pojedynczego strzału do obliczeń przyjęto czas równy 100 ms. Wyniki obliczeń uzyskano za pomocą MES zaimplementowanego w oprogramowaniu COMSOL Multiphysics ver. 5.6.

13

Study on the influence of chamfer perforation on heave and pitch of a single floating platform

Wang Wei, Fan Sheming, You Yunxiang, Zhao Cheng, Xu Liqun, Wang Guibiao, Lu Zhiqiang

Polish Maritime Research

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2023

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nr 1

43--53

EN

The aim of this work is to study the influence of chamfered perforation and chamfering on the heave and pitch motion of a single floating wind power platform with an anti-heave device. Firstly, the hydrodynamic performance of a single floating body with different chamfers, or without perforation, is calculated and analysed. Secondly, the motion of a model without perforation and with 35° chamfered perforation is captured and studied in a towing tank. The results show that when the wave height is large and the period is small, the perforated device has a certain effect. When the wave height and period are small, the pitch suppression effect of chamfered perforation is more obvious than that of non-chamfered perforation. When the period and wave height are large, the heave suppression effect of non-chamfered perforation is better than that of chamfered perforation. In experimental research, the perforated floating body has a certain effect on restraining the heave and pitch of a floating body under most working conditions, and the effect of restraining the pitch is obviously better than that of restraining the heave.

14

CFD-DEM simulation of raceway size and mechanical characteristics of industrial scale blast furnace

Gao Yuzhen, Chan Choon Kit

Polish Journal of Chemical Technology

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2023

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Vol. 25, nr 3

71--78

EN

The raceway plays a crucial role in ensuring the stable functioning of the ironmaking blast furnace. It is the key site where the chemical reaction of coke combustion takes place, providing the necessary heat and reducing gas for the upper iron ore reduction process. Consequently, the size of the raceway serves as an essential indicator of the blast furnace’s operational condition. In this study, a mathematical model for the raceway of an industrial-scale blast furnace was established. Extensive innovation investigations were conducted to explore the characteristics pertaining to the raceway’s size. The simulation outcomes demonstrate that both the particle size and the inlet velocity exert significant influences on the raceway dimensions. Specifically, the height of the raceway is predominantly affected by the particle size, whereas the inlet velocity predominantly influences the depth of the raceway.

15

The influence of air inlet layout on the inner flow field for a vertical turbo air classifier

Yu Yuan, Li Xingshuai, Zhang Yu, Jiao Zhiwei, Liu Jiaxiang

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 6

art. no. 175859

EN

In this study, the influence of air inlet layout on the flow field distribution and particle movement trajectory for the vertical turbo air classifier are analyzed comparatively using the numerical simulation method. The air inlet layout adjustment can increase the axial velocity and turbulent dissipation rate at the feeding inlet and do not generate the axial negative velocity, which improves powder material pneumatic transportation and dispersion capacity; the air inlet layout adjustment can match the airflow rotation direction with the rotation direction of the rotor cage, which can eliminate the vortices in the rotor cage channel effectively. Moreover, the particle movement time is shortened and fast classification is completed, which can decrease the particle agglomeration probability and weaken the ‘fish-hook’ effect. The optimization scheme of the air inlet layout is Type-BC. In accordance with the numerical simulation results, the calcium carbonate classification experimental results indicate that the classification performance of the classifier is improved using Type-BC.

16

Effect of spiral vanes width on the separation performance of a hydrocyclone

Liu Peikun, Wang Xiaoguo, Jiang Lanyue, Zhang Yuekan, Yang Xinghua, Li Xiaoyu, Wang Hui

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 6

art. no. 173563

EN

Aiming at the problem of “entrainment fine particles in underflow” of hydrocyclone in grinding and classification process, a hydrocyclone with spiral vanes (the SV hydrocyclone) was proposed. The CFD techniques were used to study the pressure field, velocity field, turbulence field, particle field and classification efficiency of hydrocyclones with spiral vanes of different widths. The results show that the pressure drop, axial velocity, tangential velocity, turbulence intensity of SV hydrocyclone are reduced in different degrees compared with conventional hydrocyclone, and the reduction becomes more obvious with the increase of vane width. In the case of a vane width of 0.04D, the underflow recovery rate of 5μm and 10μm fine particles was reduced by 16.2% and 15.7%. The selection of spiral vanes with small widths is beneficial to improve the separation accuracy of fine particles and reduce the cut particle size.

17

Towards an Optimal Motor Mounting Bracket Using Topology Optimization Combined with Sustainability and Manufacturing Cost Analysis

Fassi Hicham Fihri, Aniyou Hadji

Management and Production Engineering Review

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2023

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Vol. 14, No. 4

109--116

EN

The engine is the most important component of a vehicle. It attaches to the main frame via the engine mounting bracket which supports weight and operating loads. The engine mount therefore plays a crucial role in the durability and comfort of the vehicle. This article contributes to the search for the most optimal model from the point of view of resistance, environmental impact, and manufacturing cost. This involves, on the one hand, optimizing the support by reducing its initial mass by 30%, and on the other hand, seeking suitable material and manufacturing process with the least environmental impact. To this end, topology optimization will be combined with an environmental assessment and a manufacturing cost analysis. Four materials will be tested and evaluated. Finally, a cost analysis will present a comparison between a conventional process and 3D printing.

18

Research on stability of rock mass and þ30 level surface construction works when re-exploiting the seam H10 at Mong Duong Coal Mine, Vietnam

Vu Tien T., Dao Doan V.

Journal of Sustainable Mining

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2023

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Vol. 22. iss. 2

100--109

EN

The re-exploitation of coal seams located near the ground is one of the solutions to increase output, reduce mining investment costs, and avoid wasting coal resources. The re-exploitation of coal seams will also cause instability of the surrounding rock mass and may affect surface construction works. Through the process of re-exploiting the longwall in seam H10 at Mong Duong Coal Mine, the authors have studied and evaluated the stability of the rock mass and þ30 level surface works (including fan station and gateroad). To achieve the results in this study, the numerical simulation model method and the analytical method were applied. The model analysis results have determined that the displacement and deformation areas of the rock mass around the mining area correspond to the length of the cut in the strike direction of the longwall H10. The analysis and calculation results from the model show that the longwall in seam H10 can be re-exploited when leaving a protective coal pillar about 50 m from the center of the þ30 fan station at the east side; this distance ensures the stability of the rock mass that located near the ground and the surface works at þ30.

19

Supporting a Mine Working with a Shelter in Various Mining and Geological Conditions

Krukovskyi Oleksandr, Krukovska Viktoriia

Inżynieria Mineralna

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2023

|

no. 1

45--52

EN

Shelters are used to protect miners from exposure to harmful gases and for the work of rescuers. Such shelters are built in a niche adjacent to the mine working. The purpose of this work is a numerical study of the stress state of a coal-rock massif with a mine working and a shelter, their stability in various mining and geological conditions and with various supporting schemes. Numerical simulation of the stress state of a coal-rock massif with a mine working and a shelter was performed; their stability was studied in various mining and geological conditions and with various supporting schemes. It is shown that, over time, near-contour rocks are unloaded from rock pressure, and an area of increased difference of the stress tensor compo-nents expands around the mine working and the shelter. This leads to cracks formation of varying degrees of intensity. When the mine working with the shelter is driven at a shallow depth in hard rocks, the basic scheme, which consists mainly of metal frames and a reinforced concrete barrier, is sufficient for their supporting. If the host rocks are weaker, the stability of the mine working and the shelter is broken and it is necessary to strengthen their supporting with rock bolts. In the bolted area, the rocks are in triaxial compression conditions, a rock-bolts arch is formed above the mine working and the shelter, which pre-vents the displacement of the roof rocks into the mine working and increases its stability. With an increase in the depth of min-ing operations, the stability of the mine working decreases; the inelastic deformation zone in the mine walls grows; the load on the support increases. For the rock-bolts arch formed in the mine roof, supports are required in the walls of the mine working and the shelter. For this purpose, side rock bolts are installed. The use of an appropriate supporting scheme leads to a de-crease of the area of inelastic deformation zone by 2.5 times and the area of the zone unloaded from rock pressure by 2.6 times. Thus, such schemes for supporting the mine working and the shelter are selected, which ensure their stability in the considered mining and geological conditions.

PL

Schrony służą do ochrony górników przed narażeniem na szkodliwe gazy oraz do pracy ratowników. Schrony takie budowane są w niszy przylegającej do wyrobiska kopalnianego. Celem pracy jest numeryczne badanie stanu naprężeń masywu węglowo-skalnego z wyrobiskiem i osłoną, jego stateczności w rożnych warunkach górniczo-geologicznych i przy rożnych układach obudowy. Wykonano symulację numeryczną stanu naprężeń masywu węglowo-skalnego z wyrobiskiem i schronem. Badano ich stabilność w rożnych warunkach górniczych i geologicznych oraz przy rożnych schematach podparcia. Pokazano, że w miarę upływu czasu skały przykonturowe odciążają się od naporu skał, a wokół wyrobiska i schronu rozszerza się obszar zwiększonej różnicy składowych tensora naprężeń. Prowadzi to do powstawania pęknięć o rożnym stopniu intensywności. Gdy kopalnia współpracująca ze schronem jest prowadzona na płytkiej głębokości w twardych skałach, do ich podparcia wystarcza podstawowy schemat, składający się głownie z metalowych ram i bariery żelbetowej. Jeżeli skały macierzyste są słabsze, stabilność wyrobiska kopalnianego i osłony jest zerwana i konieczne jest wzmocnienie ich podparcia kotwami skalnymi. W rejonie kotwionym skały znajdują się w stanie trójosiowego ściskania, nad wyrobiskiem i schronem tworzy się łuk kotwowy, co zapobiega przemieszczaniu się skał stropowych do wyrobiska i zwiększa jego stateczność. Wraz ze wzrostem głębokości eksploatacji zmniejsza się stabilność wyrobiska górniczego, powiększa się strefa odkształceń niesprężystych w ścianach kopalni, obciążenie podpory wzrasta. Dla łuku kotwiowego formowanego w stropie kopalni wymagane są podpory w ścianach wyrobiska i schronu. W tym celu montowane są boczne kotwy skalne. Zastosowanie odpowiedniego schematu podparcia prowadzi do 2,5-krotnego zmniejszenia powierzchni strefy odkształceń niesprężystych oraz 2,6-krotnej powierzchni strefy odciążonej od parcia skał. W związku z tym dobierane są takie schematy obudowy wyrobiska i osłony, które zapewniają ich stabilność w rozważanych warunkach górniczo-geologicznych.

20

Numerical simulation of hydrogen storage in the Konary deep saline aquifer trap

Luboń Katarzyna, Tarkowski Radosław

Gospodarka Surowcami Mineralnymi

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2023

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T. 39, z. 3

103--124

EN

Nowadays, hydrogen is considered a potential successor to the current fossil-fuel-based energy. Within a few years, it will be an essential energy carrier, and an economy based on hydrogen will require appropriate hydrogen storage systems. Due to their large capacity, underground geological structures (deep aquifers, depleted hydrocarbon fields, salt caverns) are being considered for hydrogen storage. Their use for this purpose requires an understanding of geological and reservoir conditions, including an analysis of the preparation and operation of underground hydrogen storage. The results of hydrogen injection and withdrawal modeling in relation to the deep Lower Jurassic, saline aquifer of the Konary geological structure (trap) are presented in this paper. A geological model of the considered structure was built, allowable pressures were estimated, the time period of the initial hydrogen filling of the underground storage was determined and thirty cycles of underground storage operations (gas injection and withdrawal) were simulated. The simulations made it possible to determine the essential parameters affecting underground hydrogen storage operation: maximum flow rate of injected hydrogen, total capacity, working gas and cushion gas capacity. The best option for hydrogen storage is a two-year period of initial filling, using the least amount of cushion gas. Extracted water will pose a problem in relation to its disposal. The obtained results are essential for the analysis of underground hydrogen storage operations and affect the economic aspects of UHS in deep aquifers.

PL

Ze względu na bardzo dużą pojemność podziemne struktury geologiczne (głębokie poziomy wodonośne, sczerpane złoża węglowodorów, kawerny solne) są rozważane do magazynowania wodoru. Ich wykorzystanie w tym celu wymaga rozpoznania uwarunkowań geologiczno-złożowych, w tym analizy przygotowania oraz pracy podziemnego magazynu wodoru. Przedstawiono wyniki modelowania zatłaczania i odbioru wodoru do głębokiego dolnojurajskiego poziomu solankowego struktury geologicznej Konary. Zbudowano model geologiczny rozważanej struktury, oszacowano dopuszczalne ciśnienia szczelinowania oraz ciśnienie kapilarne nadkładu, wyznaczono długości wstępnego okresu zatłaczania wodoru do podziemnego magazynu, przeprowadzono modelowanie przebiegu 30-letniej pracy podziemnego magazynu (zatłaczania i odbioru gazu). Przeprowadzone symulacje umożliwiły określenie istotnych parametrów wpływających na prace podziemnego magazynu wodoru: maksymalną wielkość przepływu zatłaczanego wodoru, pojemność całkowitą, pojemność roboczą i wielkość poduszki gazowej. Pozwoliły stwierdzić, że im dłuższy wstępny okres zatłaczania wodoru, tym większą musimy zastosować poduszkę gazową. Za najlepszą opcję dla magazynowania wodoru zaproponowano dwuletni okres wstępnego zatłaczania gazu do struktury; opcja z najmniejszą wielkością poduszki gazowej. Stwierdzono, że ilość wody, jaka jest eksploatowana w trakcie odzyskiwania wodoru, podczas cyklicznej eksploatacji magazynu, spada wraz ze zwiększeniem długości wstępnego okresu zatłaczania wodoru. Eksploatowana woda będzie stanowiła znaczący problem związany z jej unieszkodliwieniem. Otrzymane wyniki są istotne w analizie pracy podziemnego magazynu wodoru i wpływają na aspekty ekonomiczne UHS w głębokich solankowych poziomach wodonośnych.