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Terrestrial laser scanning in the construction of a numerical model geometry related to underground post-mining facility

Bodlak Maciej, Izydorski Jakub

Studia Geotechnica et Mechanica

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2024

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Vol. 46, nr 2

125--134

EN

The procedure of building a quasi-3D geometry of a numerical model of an underground post-mining facility is presented in the article. For this purpose, measurements were made, based on the terrestrial laser scanning (TLS) technology, of a fragment of St. John adit, which is part of the underground tourist route “Geopark” St. Johannes Mine in Krobica in Lower Silesia in Poland, in the neighborhood of Krobica, Gierczyn and Przecznica – the places located in the vicinity of the well-known health resort Świeradów Zdrój. TLS, as one of the most advanced mining surveying technologies, enables accurate mapping of even the most complex geometries of underground mining facilities. This opens wide possibilities in the construction of more accurate numerical models of the behavior of the rock mass around such underground objects. As a result, more reliable calculation results are obtained, which are the basis for designing mining support protection, for example, with rock bolting. This translates into an improvement in the safety of underground excavations, in the conditions of exploitation in mining as well as in historical post-mining excavations made available to tourists. In the construction of the geometry of numerical model, software such as Trimble RealWorks was used to orientate individual “point clouds” from measurement stations. CloudCompare software was also used to generate cross sections to the adit axis, and AutoCad software was used for processing and spatial orientation of a selected characteristic cross section. Using the latest version of the FLAC 3D v.9.0 software, the excavation cross-section geometry obtained from measurements was mapped to and discretized (i.e., meshed), giving it a third dimension at the same time.

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Numerical modeling of heat transfer and flow field in a novel calcinator

Zhou Tie-zhuang, Yang Bin, Wang Cheng-qiang

Polish Journal of Chemical Technology

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2024

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Vol. 26, nr 2

31--41

EN

This study focused on investigating the heat transfer and flow dynamics of a catalyst granule within a pilot calciner, employing both numerical modeling and computational fluid dynamics. The research comprised two primary components: (1) Simulation of the gas flow within the pilot calciner using the Eulerian–Eulerian approach, treating gases and catalyst particles as distinct phases – gas and granular. The model, encapsulating both heat transfer and flow processes, was developed in Fluent software version 16.0. Its accuracy was confirmed against empirical data from a pilot-scale calciner unit. (2) Subsequent to validation, the model was utilized to examine the distribution characteristics within the flow field, including the temperature profiles of gas and particles, the vector velocity field of the gas across different phases, and the overall heat transfer coefficient. This investigation aims to enhance the understanding of the complex heat transfer and flow dynamics in calciners, facilitating the optimization of operational parameters, performance, and structure of pilot-scale equipment. Furthermore, it provides foundational data pertinent to the future exploration of real-world industrial applications.

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Knowledge Transfer Platform FindFISH – Numerical Forecasting System for the Marine Environment of the Gulf of Gdańsk for Fisheries

Dzierzbicka-Głowacka Lidia, Janecki Maciej, Dybowski Dawid, Nowicki Artur, Zaborska Agata, Pieckiel Piotr, Wójcik Michał, Kuczyński Tomasz, Wittbrodt Jacek

Oceanologia

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2024

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Vol. 66 (2)

334--352

EN

Fast access to expert knowledge is very valuable, especially in the context of decision-making. Fishermen can use this knowledge to diagnose hydrological and hydrochemical conditions in which fish stocks should be the most abundant. In response to this need, a digital service has been developed. It is a service created within the FindFISH project, which provides the results of all developed models: hydrodynamic, biochemical, and Fish – for selected commercially caught fish species (herring, sprats, cod, and flounder). Our research revealed that the FindFISH service can enhance fishing efficiency and quality by approximately 40%, significantly increasing expected profits. In practical applications, we observed a 50% to 70% concordance between the fishing grounds recorded by fishermen and those identified by the FindFISH Platform. The website runs dynamically in operational mode, allowing visualization of forecasts in the form of maps, time series, spatial data, and tables.

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Numerical modeling of a potential CO2-supplied enhanced geothermal system (CO2-EGS) in the Asgard field, Norway

Miecznik Maciej, Tyszer Magdalena, Sowiżdżał Anna, Andresen Trond, Frengstad Bjorn S., Stenvik Lars A., Pierzchała Karol, Gładysz Paweł

Geology, Geophysics and Environment

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2024

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Vol. 50, no. 2

175--190

EN

The principle of Enhanced Geothermal System (EGS) technology is that water injected at a sufficiently high pressure will lead to the fracturing of naturally impermeable rocks, and as a result, this will create hydraulic communication between wells. In this way, reservoirs not previously considered to be perspective can provide geothermal heat to the surface. Since nearly two decades, CO2 is considered, mostly theoretically, as a working fluid that can potentially provide higher net power output than water in EGS’s installation. In this respect, the possibility of accessing high-temperature heat from the Are and Tilje formations located on the shelf of the Norwegian Sea was analysed. The estimated temperature at the reservoir depth of 4,500–5,000 m is not less than 165°C. For this, a 3D numerical modelling was performed in order to analyse 10 different scenarios for heat extraction using supercritical CO2 (sCo2) as a working fluid. Results indicate that appropriate matching of the mass flow and temperature of the injected CO2 allows to avoid premature temperature decline in the reservoir. However, as Are and Tilje formations are built from highly porous and relatively highly permeable rocks, the fluid entering the production well will always be a mixture of CO2 and water. This is advantageous from the point of view that a significant part of the injected CO2 is trapped in the reservoir, while the higher water content in the production well allows a significant temperature drop during fluid extraction to the surface to be avoided.

5

The importance of transboundary aquifer management between Poland and Ukraine for the protection of common water

Solovey Tatiana, Janica Rafał, Harasymchuk Vasyl, Przychodzka Małgorzata, Medvid Halyna, Yanush Liubov

Geological Quarterly

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2023

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Vol. 67, No. 3

art. no. 33

EN

Transboundary hydrogeological units between Poland and Ukraine within the Bug and San River basins are identified, based on harmonized geological and hydrogeological data used for development of a numerical simulation of groundwater flows across the state border. This numerical model shows that the cross-border exchange of groundwater in aquifers takes place in a limited area and the flow pattern can be disturbed by the groundwater exploitation. Abstraction at current levels slightly increases the transboundary groundwater flow from Poland to Ukraine and minimally reduces the flow in the opposite direction, though not reversing the direction of water flow at the border. The simulated drawdowns do not have a transboundary range, but negative effects on surface water resources are noticeable. Estimates show that groundwater runoff to rivers decreased and infiltration losses through the riverbed increased. The quantitative status of the transboundary aquifers has not deteriorated significantly under the current exploitation but in the light of ambitious maximum allowable values for water abstraction, and in the absence of joint resource management, this problem will arise in the near future. Joint management should focus on a broader legal consensus, improvement of institutional relations, and integration of monitoring and groundwater status assessment systems.

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A description of the sources of magnetic field using edge values of the current vector potential

Wojciechowski R. M., Jędryczka C.

Archives of Electrical Engineering

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2018

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Vol. 67, nr 1

17--26

EN

The paper discusses the method of a description of the magnetic field sources in systems with the stranded windings. The sources are determined on the basis of an obtained distribution of edge values of the current vector potential T0. The formulas describing the magnetic field sources in the finite element (FE) space for the formulations using the scalar potential F and the vector potential A have been given. The approach for determining the T0 distribution in the stranded windings of simple and complex geometries has been proposed.