Rudarsko-geološko-naftni zbornik
https://hrcak.srce.hr/ojs/index.php/rgn
<p>The<strong> "Zbornik" is one of the leading Croatian scientific journals</strong> for different topics from Earth sciences, different engineering and similar fields. It is entirely open access (green model, CC-BY, <a href="http://www.sherpa.ac.uk/romeo/pub/2374/">http://www.sherpa.ac.uk/romeo/pub/2374/</a>), without any hidden author's fees. <strong>Please, use "Make a Submission" button (homepage) </strong>for sending manuscript into journal. Published by the Faculty of Mining, Geology and Petroleum Engineering (https://www.rgn.unizg.hr/en/) as part of the University of Zagreb (http://www.unizg.hr/homepage/).</p>en-US<p>Creative Commons-BY</p> <p>Authors who publish with this journal agree to the following terms:</p> <div> <p><strong>In agreeing this form, you certify that:</strong></p> </div> <ol> <li>You read the ethical codex of the <em>RGN zbornik</em> available at journal web.</li> <li>You submitted work is your original work, and has not previously been published and does not include any form of plagiarism.</li> <li>You own copyright in the submitted work, and are therefore permitted to assign the licence to publish to <em>RGN zbornik</em>.</li> <li>Your submitted work contains no violation of any existing copyright or other third party right or any material of an obscene, libellous or otherwise unlawful nature.</li> <li>You have obtained permission for and acknowledged the source of any illustrations, diagrams or other material included in the work of which you are not the copyright owner.</li> <li>You have taken due care to ensure the accuracy of the work, and that, to the best of your knowledge, there are no false statements made within it.</li> <li>All co-authors of this submitted work are aware of, and in agreement with, the terms of this licence and that the submitted manuscript has been approved by these authors.</li> </ol> <p> </p> <div> <h2>Publication licence</h2> </div> <p>You retain copyright in your submitted work, according to journal license policy (CC-BY). By signing this form you agree that <em>RGN zbornik</em> may publish it under the publication licence. In summary the licence allows the following:</p> <p>Anyone is free:</p> <ul> <li>To copy, distribute, display, and perform the work.</li> <li>To make derivative works.</li> </ul> <p> </p> <p>Under the following conditions:</p> <ul> <li>The original author must always be given credit.</li> <li>The work may not be used for commercial purposes.</li> <li>If the work is altered, transformed, or built upon, the resulting work may only be distributed under a licence identical to this one.</li> </ul> <p> </p> <div> <h2>Exceptions to the licence</h2> </div> <p>In addition to publishing the work printed under the above licence, <em>RGN zbornik</em> will also enable the work to be visible online.</p> <p><strong>The journal editorial can change the licence rules anytime but it cannot retroactively restrict author(s) rights.</strong></p> <p> </p>tomislav.korman@rgn.unizg.hr (Tomislav Korman, Editor-in-Chief)tkorman@rgn.hr (Tomislav Korman, Editor-in-Chief)Tue, 11 Feb 2025 11:28:08 +0100OJS 3.2.1.4http://blogs.law.harvard.edu/tech/rss60The Effect of Rumen Fluid Application on Various Coal Types in Methane Production
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32513
<p>Indonesia is one of the largest coal producers in the world. The conversion of coal into coalbed methane (CBM) by involving methane-producing microbes appears to be a potential alternative to utilizing coal for energy resources. One possible source of methanogens is rumen fluid collected from slaughterhouse waste. Previous studies have reported the possibility of employing rumen fluid to produce methane from coals. To sustain field application, microbiological testing of rumen fluid in CBM reservoir circumstances is required. Therefore, various water formations and coals were involved in the present study. The present study aims to identify methane production by combining rumen fluid as methane-producing microbes, formation water, and various coal types (A: lignite, B: sub-bituminous, C: bituminous, and K: control) at room temperature. The results suggest that supplying microbes from rumen fluid and formation water can produce methane from different types of coal. Microbial activity in all treatments is denoted by pH changes and observing living microbes. Bacilli are the predominant type of microorganism. Due to coal organic compound breakdown, the presence of methanogenic microbial activity is denoted by volatile fatty acids (VFA). The total VFA in all treatments demonstrated a similar declining tendency. It was found that all treatments produce volatile fatty acids in different amounts up to 60 days of incubation. These acids included acetic, propionic, butyric, iso-butyric, iso-valeric, and valeric acids. Acetic acid is the most commonly produced partial VFA, the primary, intermediate compound in methane formation. Treatment A with lignite coal had the maximum gas production. The cumulative gas volume reached 16,400 mL after 60 days of incubation. In contrast, the highest cumulative methane production occurred in treatment C with bituminous coal, amounting to 100.60 mL after 60 days of incubation.</p>Dahrul Effendi, Asep Kurnia Permadi, Doddy Abdassah, Bambang Widarsono
Copyright (c) 2025 Dahrul Effendi, Asep Kurnia Permadi, Doddy Abdassah, Bambang Widarsono
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32513Tue, 11 Feb 2025 00:00:00 +0100Improving the quality of silica sand as a proppant for hydraulic fracking industry purposes
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32094
<p>A technological silica sand sample that belongs to "Egypt's Future Quarries", south west Cairo, was investigated as a proppant for the hydraulic fracking industry. The sample showed encouraging physical and mechanical characteristics, yet it was still in need of improving its grade to match the International Organization for Standardization specifications. After careful reading of the microscopy and mineralogy investigation of the head sample, a simple and cheap beneficiation flowsheet was suggested including sieve classification and an attrition scrubbing technique using a 50-liter capacity “Denver” machine. The results showed appreciable grade improvement in the attrition sand. An increase in silica content from 90.10% to 98.15% SiO<sub>2</sub> at the expense of alumina and iron oxides %’s by 79% and 63%, respectively. This grade improvement subsequently led to notable improvement in turbidity and acid solubility measures and hence, transformed the sand sample from being unacceptable for the oil and gas industry to a sand product with acceptable specifications for this industry. The results also showed improvement in the crushability resistance and grain sphericity and roundness measures with ratios reaching 24.06%, 19.11% and 16.72%, respectively. In addition, particle size distribution of the attrition sand showed more consistency, which is desirable for the fracking industry.</p>Suzan S. Ibrahim, Tawfik Refaat Boulos, Sameh Abdullah, Abdullah Elbendary, Mohamed Khalifa, Ayman Hagrass
Copyright (c) 2024 Suzan S. Ibrahim, Tawfik Refaat Boulos, Sameh Abdullah, Abdullah Elbendary, Mohamed Khalifa, Ayman Hagrass
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32094Tue, 11 Feb 2025 00:00:00 +0100Middle-Late Miocene Tidal-related Deposits of the Binio Formation: the Sedimentary and Stratigraphic Records during Inversion of the Central Sumatra Basin, Indonesia
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32419
<p>The distribution of tidal-related deposits can be controlled by structural growth. This structural growth can be reflected, for example, by inversion structures in a back-arc basin. An example of such a structure is found in the Central Sumatra Basin (CSB), Indonesia. However, there are limited detailed studies using 3D seismic, well, and core data to understand how structural growth controls sedimentary processes and tidal deposit distribution in the CSB. This study utilizes these data to investigate the sedimentary processes and distribution of the Middle-Late Miocene Binio Formation, which was deposited during basin inversion. Sedimentological analysis, sequence stratigraphy, and Root Mean Square (RMS) attribute analysis were conducted on these data. Sedimentological analysis of the core data revealed the presence of tidal sand body and open marine facies. Furthermore, by integrating gamma-ray log and laboratory data, parasequences bounded by flooding surfaces were identified. The stratigraphic framework showed that the tidal sand body occurred before and after maximum flooding surfaces, forming transgressive and regressive tidal sand ridges. RMS attribute analysis indicated a consistent NW-trending orientation of these ridges near the flooding surfaces, implying the influence of a NW-trending tidal current, and a NE-trending paleo-shoreline near the Barisan Mountain, which affected sedimentary distribution and paleogeography during the Middle-Late Miocene. Additionally, the investigation of the relationship between ridges and reverse faults revealed that the ridges were likely controlled by tectonic activity. This study highlights that the temporal and spatial evolution of the ridges in the CSB was driven by the interaction between sediment supply and accommodation space, likely influenced by reverse fault growth and sea-level variations.</p>Aurio Erdi, Afrizon Setiawan, Ismail Zulmi, Alan Rene Inabuy, Rifati Hanifa Az Zahra, Eric Edwin, Ivan Praja Andhika, Dany Auliansyah, Edward Wijaya
Copyright (c) 2024 Aurio Erdi, Afrizon Setiawan, Ismail Zulmi, Alan Rene Inabuy, Rifati Hanifa Az Zahra, Eric Edwin, Ivan Praja Andhika, Dany Auliansyah, Edward Wijaya
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32419Tue, 11 Feb 2025 00:00:00 +0100Subsurface Structural Modelling using the Gravity Method in the Pacitan Area, Indonesia based on Derivative Analysis and Model Inversion
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32144
<p>The southern part of Java is dominated by volcanoes covered by thick and young volcanic deposits. Due to the complex subsurface conditions, active geophysical techniques such as seismic reflection cannot be used in this volcanic area. However, the gravity method provides a suitable alternative for geophysical exploration in this challenging environment. Gravity data obtained from satellite measurements was used to create Bouger anomaly maps to overcome this. Structural analysis in this research used derivative analysis, namely, first and second horizontal derivatives. The modelling was done using an inverse model, and the inversion process was carried out using the SVD and Occam methods. In conducting the structural analysis and inversion model, the data used is residual anomaly data obtained from the complete Bouger anomaly by carrying out the previous bandpass filter. The research produces a subsurface model detailing the geological features of the study area, including the basin and structural formations.</p> <p>Two cross-sections, A-A' and B-B', were created to interpret the geological model from north-south and west-east directions. The formations and values of both density and density contrast found in the study area according to rock age from old to young are the Arjosari Formation (-0.3 - -0.28 gr/cm<sup>3</sup>), the Mandalika Formation (-0.28 - -0.25 gr/cm<sup>3</sup>), Intrusion (0.25 – 0.4 gr/cm<sup>3</sup>), the Jaten Formation (-0.1 – 0.25 gr/cm<sup>3</sup>), the Wuni Formation (-0.25 - -0.2 gr/cm<sup>3</sup>), and the Nampol Formation (-0.2 - -0.1 gr/cm<sup>3</sup>). These revealed six rock formations in cross-section A-A' and three rock formations in cross-section B-B'. The density values of various formations were also determined. The reverse faults, strike-slip faults, and normal faults were the geological structures found. The analysis also identified two sedimentary basins, the Wonogiri basin and the Pacitan basin, with a depiction of the Pacitan sub-basin in the B-B' section.</p>Ajimas Pascaning Setiahadiwibowo, Ari Setiawan, Salahuddin Husein, Sismanto Sismanto
Copyright (c) 2024 Ajimas Pascaning Setiahadiwibowo, Ari Setiawan, Salahuddin Husein, Sismanto Sismanto
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32144Tue, 11 Feb 2025 00:00:00 +0100Analysis of Atterberg limits of clayey soils exposed to pollutants
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32470
<p>The issue of soil pollution has become a global concern due to the extensive and accelerated industrial development since the Industrial Revolution. Various anthropogenic activities, including industrial processes and agricultural practices, introduce pollutants into the soil. These pollutants vary widely in type and concentration, and they pose significant risks to both the soil ecosystem and the surrounding environment. This study is part of an extensive series of laboratory investigations aimed at examining how different pollutants—specifically hydrocarbons, detergents, and pesticides—affect the geotechnical properties of clayey soils in Hungary. The primary focus of this research is to analyze the changes in the Atterberg limits of these soils when exposed to different pollutants. The laboratory tests were conducted in strict accordance with Eurocode standards to ensure the reproducibility of the results and consistency in the experimental procedures. The findings elucidate the distinct impacts of various pollutants on the Atterberg limits across different types of clay. The insight gained from this research can significantly enhance the efficiency, safety, and cost-effectiveness of geotechnical engineering projects.</p>Noémi Szász, Andrea Tóth
Copyright (c) 2024 Noémi Szász, Andrea Tóth
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32470Tue, 11 Feb 2025 00:00:00 +0100Enhancing Iron Separation and Recovery from Egyptian Banded Iron Formation Using Paper Industry Sludge: A Sustainable Reduction Roasting Approach
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32536
<p>This paper proposes an innovative method to upgrade Um Nar Banded Iron Formation (BIF). The method consists of three stages: reduction roasting using paper industry sludge and sawdust, sulfuric acid leaching, and magnetic separation. The effects of CaCO<sub>3</sub>/sawdust concentration and magnetic field intensity were examined. This approach not only provides an effective means of processing complex and low-grade iron ores but also offers a sustainable solution for recycling industrial waste. Additionally, it utilizes biomass sawdust as a green reducing agent, a new type of clean energy source with low sulfur content, which does not pollute the environment. Adding paper industry sludge as calcium carbonate (CaCO<sub>3</sub>) led to its reaction with Si and Al minerals, forming grossular (Ca<sub>3</sub>Al<sub>2</sub>(SiO<sub>4</sub>)<sub>2</sub>(OH)<sub>4</sub>). This prevented SiO<sub>2</sub> from reacting with iron oxides, thereby enhancing iron recovery. The resulting iron concentrate meets the quality standards necessary for steel production. The iron concentrate obtained through this method, i.e. reduction roasting conducted with 10% dosage of reductant, followed by acid leaching and magnetic separation at 2000 gauss, contains 67.23% total Fe and 1.5% SiO<sub>2</sub> with a total Fe recovery of 73.82%, meeting the iron ore quality requirements of the steel and iron industry.</p>Mostafa Metwally, Mohamed G. Farghaly, A. M. Ramadan, El-Sayed R. E. Hassan
Copyright (c) 2024 Mostafa Metwally, Mohamed G. Farghaly, A. M. Ramadan, El-Sayed R. E. Hassan
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32536Tue, 11 Feb 2025 00:00:00 +0100Investigating the feasibility of using recycled fibres instead of industrial fibres in shotcrete
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32318
<p>Shotcrete is one of the standard systems used in the tunnelling industry, including cement, sand, water, and additives. Adding fibres to shotcrete is a method to enhance its mechanical properties. This study is laboratory research investigating the feasibility of using recycled steel fibres instead of industrial fibres and the effect of adding industrial and recycled fibres on the mechanical properties of shotcrete. For this research, laboratory samples were created using industrial steel fibres and recycled steel fibre types 1 and 2 sourced from worn tires. Laboratory samples include cubic and cylindrical samples with 12 mixing designs. These 12 mixing designs are plain shotcrete, shotcrete containing 1, 2, and 5 percent industrial steel fibres, shotcrete containing 0.5, 1, 1.5, and 2 percent type 1 recycled fibre, and shotcrete containing 0.5, 1, 1.5, 2 percent type 2 recycled fibres. Laboratory tests include compressive strength, tensile strength, and modulus of elasticity for durations of 3, 7, and 28 days. According to the results, adding industrial and recycled fibres to the shotcrete composition improves the resistance properties of shotcrete, and recycled fibres can replace industrial fibres.</p>Shahla Miri Darmarani, Erfan Khoshzaher, Hamid Chakeri , Rahman Mirzaei
Copyright (c) 2024 Shahla Miri Darmarani, Erfan Khoshzaher, Hamid Chakeri , Rahman Mirzaei
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32318Tue, 11 Feb 2025 00:00:00 +0100Method for limiting the heating of air supplied to deep workings of coal mines
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32244
<p class="Text">The purpose of this paper is to substantiate the arrangement of workings that supply cooled air to the faces based on an assessment of changes in the energy state of the rock mass under the influence of mining operations. The theoretical studies were carried out based on a systematic analysis of the fundamental equations of the classical theory of thermodynamics, taking into account experimental data on rock physics and geomechanical processes occurring during mining operations. This purpose was achieved by comparing the energy state (enthalpy) of rocks in the mass intact by mining operations and the mass formed in these rocks after coal seam extraction. The authors proposed the idea of transporting refrigerant in the form of cooled air through the workings arranged in the displaced rocks behind the longwall, which are relieved of rock pressure, degassed and cooled. This makes it possible to significantly reduce cold losses on the way to the miners’ workplaces. The results of theoretical preliminary calculations confirm that the enthalpy of displaced rocks in the mined-out longwall space remains virtually unchanged regardless of the depth of mining. This confirms the validity of the idea of choosing the arrangement of the workings to save cold. The linear nature of the increase in the ratio of rock enthalpy in intact and cooled rock masses during the deepening of mining operations has been established, which proves the efficiency and prospects of the proposed method for large depths. A variant of coal seam preparation and mining is proposed to ensure the saving of the cold resource by arranging workings in displaced and cooled rocks.</p>Viktor Kostenko, Iaroslav Liashok, Olha Bohomaz, Maryna Tavrel, Tetiana Kostenko
Copyright (c) 2024 Viktor Kostenko, Iaroslav Liashok, Olha Bohomaz, Maryna Tavrel, Tetiana Kostenko
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32244Tue, 11 Feb 2025 00:00:00 +0100Numerical optimization of the EFP charge based on an MPB mine
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32530
<p>This article presents a numerical optimization of an explosively formed charge insert based on an anti-bullet, anti-tank MPB mine (<em>pl. mina przeciwburtowa, eng. </em><em>anti-side mine</em>). For this purpose, first of all, the chemical composition and microstructure of the currently used EFP inserts and the target material - armour-piercing steel - were analyzed. Then, a series of numerical analyses were carried out, during which not only the material of the EFP insert was changed, but also its thickness, in terms of the most efficient combination, i.e. the initial speed during forming, but also the penetration ability of the insert. The Johnson-Cook constitutive strength model was used to describe the behaviour of materials in the computational environment, and the Jones-Wilkins-Lee model was used to describe the pressure during a detonation. To describe the formation of the EFP charge, SPH particle hydrodynamics was used, which the author had developed in his previous works, thanks to which it was possible to efficiently describe the highly dynamic process. The last element of the research was the validation of numerical models carried out at a military training ground during an experimental study. The results obtained as a result of numerical analyses allowed for the determination of the most optimal combination of material and insert thickness, which indicated future directions of development in order to improve solutions in the field of anti-tank EFP.</p>Dariusz Pyka
Copyright (c) 2024 Dariusz Pyka
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32530Tue, 11 Feb 2025 00:00:00 +0100Central Sumatra Basin: The First Sedimentary Basin for Geothermal Energy Development in Indonesia?
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/31005
<p>Indonesia heavily relies on the volcanic arc as an area for geothermal energy exploration and exploitation. Several Geothermal Power Plants (GPP) such as Sibayak (North Sumatra), Sarulla (North Sumatra), Salak (West Jawa), and Kamojang (West Java) use energy within the Quaternary volcanic arc region. However, alongside the Central Sumatra Basin (CSB), which exhibits strong heat flow, the construction of power plants clashes with socio-economic and environmental concerns. Therefore, this research aimed to use geothermal data from 326 oil wells in the CSB in order to better understand the geothermal and geological features, as well as the opportunities for energy development. The results showed that the outcropping rocks in the CSB have low to very high thermal conductivity (from 1.7 to over 2.1 W/m°C), as well as very high values of geothermal gradient (from 30 to over 120°C/km), and a heat flow ranging from 70 to >150 m/Wm<sup>2</sup>. As a result, the CSB became known across the world as the sedimentary basin with unusually strong heat flow. This elevated heat flow in the CSB originated from the upwelling asthenosphere, triggered by processes such as slab roll-back and pull-apart during the Tertiary age. The processes led to a significantly thin crustal thickness of 27 km in the CSB, along with the formation of normal faults. Comparative analysis with other basins worldwide underscored the enormous potential for geothermal exploitation within the CSB. This research was expected to redirect the focus of geothermal energy adoption towards the CSB, to minimize social and environmental effects while striving for zero emissions by 2060.</p>Luhut Pardamean Siringoringo, Zakaria Situmeang, Novita Meka
Copyright (c) 2024 Luhut Pardamean Siringoringo, Zakaria Situmeang, Novita Meka
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/31005Tue, 11 Feb 2025 00:00:00 +0100Experimental Investigation of Mechanical Properties and Durability of the Self-Compacting Geopolymer Mortar using various Mineral Additions
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32067
<p class="Text">A geopolymer is an unconventional inorganic binder prepared by an alkaline activator of alumina and silica-containing materials. This study has thoroughly evaluated the strength and durability performance of geopolymer mortars and represents a comprehensive attempt to highlight the advancement of environmentally conscious and innovative construction materials. The methodology used in this study includes X-ray diffraction (XRD), a scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), universal testing machines, and chemical methods (acid, sulfate, and chloride attack). The mechanical properties and durability of geopolymer mortars made at constant temperatures are evaluated and compared using different mineral additives. A comparative analysis of geopolymer mortar shows that M3 (fly ash) is an excellent choice for structural elements in construction projects where high strength and durability are paramount, as M3 (fly ash) has achieved the highest compressive (17.07 MPa) and flexural strengths (2.28 MPa) at all curing periods compared to M2 (RHA) and M1 (slag), which have intermediate (11.66 MPa, 2.17 MPa) and the lowest (10.10 MPa, 2.04 MPa) compressive and flexural strengths, respectively. In cases where acid resistance is a critical factor for construction, M1 appears to be the most suitable option, while M2 and M3 may require additional protective measures. M1, despite having slightly lower strength values than M2 and M3, demonstrates exceptional resistance to chloride attacks, making it a preferred option for projects in moderately chloride-rich environments. The compacted material increased strength and durability, while cracks, pores, and non-uniform particle arrangement reduced it. Overall, the abundance of minerals with elemental compositions such as Si, Al, O, and Na is responsible for the strong bonding for the cementation of geopolymer concrete. Therefore, keeping in mind the results of this study, different geopolymer mortars can be selected for construction purposes based on the demands of the projects.</p>Ihtisham Islam, Salman Ahmed Khattak, Petros Petrounias, Abdul Rahim Asif, Syed Samran Ali Shah, Kanishka Sauis Turrakheil, Waqas Ahmed, Mehboob Ur Rashid, Qasim Ur Rehman, Muhammad Naveed Khan
Copyright (c) 2024 Ihtisham Islam, Salman Ahmed Khattak, Petros Petrounias, Abdul Rahim Asif, Syed Samran Ali Shah, Kanishka Sauis Turrakheil, Waqas Ahmed, Mehboob Ur Rashid, Qasim Ur Rehman, Muhammad Naveed Khan
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/32067Tue, 11 Feb 2025 00:00:00 +0100The development of the numerical method for simulation of metal material quenching
https://hrcak.srce.hr/ojs/index.php/rgn/article/view/31695
<p>Quenching is a general term for the rapid cooling of an austenitized hardenable steel or a solution treated aluminum alloy in liquid mediums with a boiling point lower than austenitization or annealing temperature. In this paper, an approach in development of a novel numerical method for computation of quenching of metal materials by immersion in liquids subjected to the Leidenfrost phenomenon has been described. Upon the known initial temperatures of the quenchant and the specimen, the numerical method by application of two-fluid VOF model solves the Stefan problem and the temperature distribution within the specimen in the first stage of quenching, in which the surface of the specimen is covered with the vapour film. The validation of the solution by comparison of the estimated temperature distribution with the experimental results from literature has been carried out, and the instantaneous distribution of the heat flow rate has been analyzed. The obtained results show the suitability of the suggested method for the numerical analysis of the initial phase of metal material immersion quenching.</p>Alen Cukrov, Darko Landek, Yohei Sato , Ivanka Boras, Bojan Ničeno
Copyright (c) 2024 Alen Cukrov, Darko Landek, Yohei Sato , Ivanka Boras, Bojan Ničeno
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https://hrcak.srce.hr/ojs/index.php/rgn/article/view/31695Tue, 11 Feb 2025 00:00:00 +0100