Wyniki wyszukiwania - BazTech

1

Numerical Simulation and Analysis of the Cavitation Noise Characteristics of an IMP Propulsor

Li Qiao, Abdullah Shahrir, Rasani Mohammad Rasidi Mohammad

Polish Maritime Research

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2026

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nr 1

74--90

EN

The objective of this study is to ascertain the cavitation noise characteristics of an integrated motor pump-jet (IMP) propulsor. The far-field cavitation radiation noise of the propulsor is analysed using computational fluid dynamics and acoustic coupling methods. The results indicate that in comparison with non-cavitation noise, the IMP propulsor generates an increased level of noise as a consequence of cavitation. Strong correlation is observed between the variables of cavitation volume pulsation and radiation noise. The initial rise in the overall sound pressure level of the radiation noise inside the propulsor is followed by a gradual increase as the degree of cavitation deepens. Concurrently, the total noise increases, while the significance of the blade frequency weakens. Variations in the blade tip gap have a pronounced influence on the intensity of cavitation noise. Under identical conditions in terms of the axial gap, the cavitation noise attains its minimum level when the radial gap is set to 3 mm. Conversely, an increase in the axial gap results in a corresponding rise in cavitation noise when the radial gap remains constant. The findings of this study will provide valuable insights for the noise control of IMP propulsors.

2

Poprawa chłonności otworów w wyeksploatowanych złożach ropnych i gazowych na potrzeby pozyskania energii geotermalnej

Moska Rafał, Czupski Marek, Masłowski Mateusz

Przemysł Chemiczny

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2025

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T. 104, nr 2

280--284

PL

Zaproponowano rozwiązania zwiększające chłonność odwiertów ropnych i gazowych, które potencjalnie mogą być wykorzystane na potrzeby pozyskania energii geotermalnej. Na przykładzie dwóch odmiennych litologicznie obszarów złożowych na terenie Polski przedstawiono koncepcje zabiegów jedno- i dwuetapowego kwasowania matrycowego w celu zwiększenia przepuszczalności zarówno w strefie przyotworowej, jak i w dalszej odległości od otworu. Wyniki laboratoryjnych testów przepływowych na rdzeniach wiertniczych oraz symulacji numerycznych pozwoliły dobrać skład cieczy zabiegowych, ich objętość oraz wydajność pompowania. Wskazano optymalne składy cieczy cechujące się wysoką efektywnością i bezpieczeństwem stosowania: ciecz na bazie kwasu organicznego i chelatów dla formacji węglanowej, ciecz wyprzedzającą na bazie kwasu octowego i chlorku amonu oraz mieszaninę kwasu solnego i fluorowodorowego jako ciecz główną dla formacji piaskowcowej.

EN

On the example of 2 deposits in Poland, the concepts of one- and 2-stage matrix acidizing treatments were presented to increase permeability both in the near-well zone and further away from the well. Seven samples were taken from each of the 2 lithographic areas and subjected to flow acidizing tests in laboratory conditions using acidizing fluids of different compn. Based on these tests and numerical calcns., the compn. of treatment fluids, their volumes as well as calc. pumping rate were detd. The optimal fluid compns. characterized by high efficiency and safe of use were indicated as org. acid and chelates for the carbonate formation and CH₃COOH and NH₄Cl as a preflush fluid, and a mixt. of HCl and HF as the main acidizing fluid for the sandstone formation.

3

Symulacje numeryczne wybranych zastosowań gruntów zbrojonych

Baca Michał

Przegląd Budowlany

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2025

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R. 96, nr 5

25--28

PL

Grunty zbrojone jako materiał budowlany mają szerokie zastosowanie w geotechnice. Pozwalają na wzmocnienie m.in. podłoża gruntowego, skarp, konstrukcji oporowych, co w konsekwencji może prowadzić do polepszenia właściwości podłoża i zmniejszenia wymiarów fundamentu. W pracy przedstawiono kilka najpopularniejszych zastosowań gruntów zbrojonych. Wykorzystując Metodę Elementów Skończonych, pokazano przykłady, jak zastosowanie gruntów zbrojonych może zmienić sposób pracy konstrukcji i wzmocnić podłoże gruntowe.

EN

Reinforced soil as a building material is widely used in geotechnics. They allow you to strengthen, among others: subsoil, slopes, retaining structures, which may consequently lead to improved subsoil properties and reduced foundation dimensions. The paper presents several of the most popular applications of reinforced soils. Using the Finite Element Method, examples were shown of how the use of reinforced soils can change the way the structure works and strengthen the ground.

4

Numerical Simulation Study of the Hydrodynamic Properties of a Floating Breakwater of Pontoons

Cheng Xiaofei, Li Shimin, Xie Wei, Xu Chenhan, Wang Junnan, Xu Tiaojian

Polish Maritime Research

|

2025

|

nr 3

47--65

EN

To address the issue of insufficient wave dissipation capacity in standard floating breakwaters consisting of pontoons, this research proposes a combined floating breakwater with T-block connections. AQWA software is used to conduct numerical simulation studies on the dissipation characteristics of waves, and the reliability of the results is confirmed by integrating them with tests of a physical model. It is found that the transmission coefficient of the combined floating breakwater increases with the wave period. When the incident wave period T<6 s, increasing the relative height of the T-block improves the wave dissipation performance; when T>6 s, the effect is weakened; and at T=8 s, the change in height is basically unaffected. Increasing the relative width of the T-block is more significant in terms of the enhancement of the wave dissipation performance, whereas the height of the incident wave has a smaller effect on the transmission coefficient, and the transmission coefficient tends to increase with the increase of the wave height only in the case where T=8 s. The height of the incident wave has little effect on the transmission coefficient. The transmission coefficient increases with the wave height only when T=8 s; when the wave period is small (e.g. 4 s), the effect of wave elimination is enhanced by increasing the draught depth, and the draught does not have a significant effect on the wave dissipation performance when T>6 s. Compared with a typical floating pontoon breakwater with a single- and double-row arrangement, the combined floating pontoon breakwater has a better effect in terms of dissipating the waves, and its advantage is significant for a period T≤6 s, with a 44% increase in the maximum wave abatement compared to a single-row arrangement. In addition, the free-motion response is analysed to clarify the effects of different factors on the transverse and pendulum motion. This study provides an important reference for the design and application of floating pontoon breakwaters.

5

Study on the formation mechanism of algal floc driven by flow field in a helical tube flocculator

Wang Chuanzhen, Zhang Yiming, Zhang Xuezhi, Zhang Haiyang

Physicochemical Problems of Mineral Processing

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2025

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Vol. 61, iss. 2

art. no. 202813

EN

The tubular flocculation reactor is a new device for the efficient treatment of algal wastewater, which has the characteristics of high removal efficiency and small dosage of chemicals. The mechanism of the influence of the flow field on the formation of floc in the pipeline has not been clarified. In this study, the effects of flow field distribution, reagent concentration and algal concentration on removal efficiency were investigated by means of experiment and numerical simulation. The results showed that the removal efficiency of the surface tubular flocculation reactor was related to the shape of the generated floc. When the size of the generated floc was greater than 900μm and the fractal dimension was greater than 1.25, the removal efficiency of the tubular flocculation reactor exceeded 90%, and the removal efficiency of the tubular flocculation reactor could eventually reach more than 98% with continued increase of the floc size and compactor degree. Under the same pipe diameter, the size and fractal dimension of flocs are linearly correlated with the proportion of inertial subregions in the flow field. After the flow rate is increased from 0.15m•s-1 to 0.3m•s-1, the non-positive region of Q criterion in the pipeline is reduced by 3%, the size of flocs is reduced by 200μm, and the fractal dimension is decreased by 0.3.

6

Effect of column segment diameter ratio on flow field and separation performance of the composite column-cone hydrocyclone

Liu Peikun, Xu Xiangxi, Yang Xinghua, Li Anjun, Chen Bo, Liu Gang, Gao Yunzhu

Physicochemical Problems of Mineral Processing

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2025

|

Vol. 61, iss. 1

art. no. 200063

EN

To address the misplacement of fine particles in the underflow caused by structural defects in conventional hydrocyclones, a composite column-cone hydrocyclone (C-C hydrocyclone) was proposed, featuring a cone-column-cone structure. Computational Fluid Dynamics (CFD) techniques were employed to study the diameter ratio and various configurations of C-C hydrocyclone, assessing the impact on separation performance. Results indicated that increasing the column section diameter ratio from 0.5 to 0.7 reduced the cutting size by 22.96 %, enhanced sharpness by 9.87 %, and improved separation efficiency. These findings offer valuable insights for the design and application of C-C hydrocyclones based on specific requirements such as grinding classification and flotation operations.

7

Estimation of thermal stresses trapped in the mast shell shaft after a fire

Gierczak Jan, Ignatowicz Rajmund Leszek

Materiały Budowlane

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2025

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nr 3

10--17

EN

This paper presents a method of analyzing a steel shell structure subjected to a momentary high‑temperature load due to a fire caused by an electrical short circuit. Based on metallographic tests and the temperature and distribution recorded during the fire by the extinguishing team, the temperature load on the mast shaft structure was numerically reconstructed. The numerical simulation results showed the formation of internal (residual) stresses after the fire‑extinguishing action, which can only be released by dismantling the structure. Based on the damaged state of the zinc coating, a method of estimating the maximum prevailing temperature during the fire was presented.

PL

W artykule przedstawiono sposób analizy stalowej konstrukcji powłokowej poddanej chwilowemu obciążeniu wysoką temperaturą na skutek pożaru wywołanego zwarciem instalacji elektrycznej. Na podstawie badań metalograficznych i zarejestrowanej temperatury oraz jej rozkładu w czasie pożaru przez zespół gaśniczy, odtworzono numerycznie obciążenie temperaturą konstrukcji trzonu masztu. Wyniki symulacji numerycznej pozwoliły wykazać powstanie naprężeń wewnętrznych (własnych), powstałych po zakończeniu akcji gaśniczej, które można uwolnić tylko przez demontaż konstrukcji. Na podstawie stanu uszkodzenia powłoki cynkowej przedstawiono sposób oszacowania maksymalnej temperatury panującej w czasie pożaru.

8

Case study of unconventional railway viaduct foundation with CDMM panels

Szczygielski Maciej

Materiały Budowlane

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2025

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nr 6

33--40

EN

Soil – cement mix panels executed with continuous deep mass mixing technology CDMM (Continous Deep Mass Mixing) are a technique employed in the foundation of viaduct, bridges, culverts and animal crossing supports, and abutments. Typically this kind of solution assume no connection between abutment and soil-cementmix panels, as such application is very limited when there are excessive horizontal forces. The solution where railway viaduct abutment is connected with panels by a special connectors in form of micropiles is presented in the paper. Ultimate and serviceability limit states are verified with numerical simulations. It is shown that CDMM technology can be an alternative for traditional piling foundations. In presented application it was also possible to avoid some specific execution problems by limiting the depth of the foundation.

PL

Panele gruntobetonowe wykonywane w technologii ciągłego wgłębnego mieszania gruntu CDMM (Continous Deep Mass Mixing), to rozwiązanie stosowane do posadowienia obiektów inżynierskich, takich jak mosty i wiadukty drogowe, przepusty oraz przejścia dla zwierząt. Zwykle tego typu posadowienie oznacza brak trwałego połączenia obiektu z gruntobetonem, a co za tym idzie nie sprawdzają się w przypadku, gdy duże obciążenia poziome mogą doprowadzić do przesunięcia bądź obrócenia się konstrukcji. W artykule przedstawiono rozwiązanie do zastosowania w tego typu sytuacjach na przykładzie posadowienia estakady kolejowej na panelach gruntobetonowych połączonych z podporami obiektu za pomocą łączników systemowych (mikropali). Stany graniczne nośności i użytkowania sprawdzono na drodze symulacji numerycznych. Wykazano, że technologia CDMM może stanowić alternatywę tradycyjnych rozwiązań posadowień palowych, a w analizowanym przypadku pozwala uniknąć dodatkowych problemów wykonawczych dzięki zmniejszeniu głębokości posadowienia.

9

Analysis of thermal and moisture properties of materials and drying of frame partitions after short-term dampness

Kosiń Mariusz, Halbiniak Jacek

Materiały Budowlane

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2025

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nr 10

198--207

EN

The use of frame structures requires the design of partitions with appropriate thermal and moisture properties. The results of material tests (sorption, water absorption, thermal conductivity coefficient) and simulation of partition drying are presented. Laboratory data confirm the high susceptibility of some of the analyzed materials to moisture absorption. Numerical analysis has shown that the partitions do not regain moisture balance even after a dozen or so months.

PL

Zastosowanie konstrukcji szkieletowych wymaga projektowania przegród o odpowiednich właściwościach cieplno-wilgotnościowych. Przedstawiono wyniki badań materiałów (sorpcyjność, nasiąkliwość, współczynnik przewodzenia ciepła) oraz symulację osuszania przegród. Dane laboratoryjne potwierdzają dużą podatność niektórych analizowanych materiałów na pochłanianie wilgoci. Analiza numeryczna wykazała, że przegrody nie odzyskują równowagi wilgotnościowej nawet po kilkunastu miesiącach.

10

Investigation on impact protection effectiveness of cushioning material in packaging container under lateral constraint condition

Zhang Zexiong, Zhong Weizhou, Li Jiaxing, Luo Jingrun

Journal of Theoretical and Applied Mechanics

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2025

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Vol. 63 nr 1

13--26

EN

A theoretical model is proposed to evaluate the impact protection effectiveness of a porous cushioning material in a packaging container under the lateral constraint condition. An acceleration-displacement equation of the protected product in the packaging container is derived. The reliability of the equation is validated by numerical simulation. Subsequently, the equation is applied to analyse the effect of strain rate on impact protection effectiveness of three polymer foams under the lateral constraint condition, and to design the thicknesses of cushioning materials in the packaging container.

11

Design of a Solidification Rate Measurement Experiment for Cast Steel in Molds Made of Different Sands Using Computer Simulation

Mordyl Natalia, Jakubski Jarosław, Żak Paweł Leszek

Journal of Casting & Materials Engineering

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2025

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Vol. 9, no. 3

39--44

EN

This article presents the design process of the casting technology for a step-shaped casting made of steel using simulation tools. A series of proposals for gating and feeding systems were simulated in the MAGMASoft® software. Results of numerical simulations allowed the Authors to select the casting technology which allows defect-free casting to be obtained. A numerical analysis of the cooling rate of a step-shaped casting made of GX70CrMnSiNiMo2 tool steel with a 5% Ti addition was carried out for the selected manufacturing technology. Due to the nature of the material used and the extended presence of martensite during cooling, in-mold hardening of the casting may occur. The simulations showed that the type of molding material affects the cooling rate, which is confirmed by the analysis of cooling curves and the morphology of shrinkage porosity. The analysis of solidification rates provides a valuable starting point and basis for subsequent research stages, taking into account the actual properties of the molding sands and the phase transformations occurring in the selected steel type. The casting technology design, which ensures the production of sound casting, was developed as part of this study. A series of simulations using different molding materials confirms the significant impact that the choice of mold material has on the casting solidification and cooling process.

12

The Behavior of Variable-Diameter Pipeline Segments on Landslides in Numerical Simulations

Kowalska-Kubsik Iwona

Inżynieria Mineralna

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2025

|

Vol. 1, no. 1

235--243

EN

The construction of pipelines in mountainous areas presents significant engineering challenges, primarily due to landslide risks and complex geological conditions. Pipelines laid on slopes are exposed to forces resulting from soil mass movements, which can lead to serious deformations or even structural failures. While minor ground displacements can often be managed without the need for costly geotechnical solutions, landslide-prone areas require precise routing, continuous monitoring, and strict adherence to safety regulations. The strategic importance of gas pipelines, combined with their vulnerability to landslide-induced damage, underscores the need for detailed geotechnical assessments and an interdisciplinary approach involving engineers, designers, and environmental specialists. Despite ongoing research into pipeline behavior under landslide conditions, there is still a lack of practical tools for predicting and preventing such damage. This article discusses the key natural and anthropogenic factors that trigger landslides and highlights the growing role of numerical modeling in analyzing pipeline performance under various landslide scenarios. Particular attention is given to the behavior of a steel pipeline in a zone of diameter transition located within a landslide area. Improving monitoring systems and developing predictive indicators are essential for reducing risk and enhancing emergency response capabilities in slope-affected regions.

PL

Budowa rurociągów w terenach górskich stanowi istotne wyzwanie inżynieryjne, głównie z powodu ryzyka osuwisk oraz złożonych warunków geologicznych. Rurociągi układane na stokach są narażone na oddziaływanie sił wynikających z przemieszczeń mas ziemnych, co może prowadzić do poważnych odkształceń, a nawet uszkodzeń strukturalnych. Podczas gdy niewielkie przemieszczenia gruntu można często kontrolować bez konieczności stosowania kosztownych rozwiązań geotechnicznych, obszary szczególnie narażone na osuwiska wymagają precyzyjnego trasowania, ciągłego monitoringu oraz ścisłego przestrzegania przepisów bezpieczeństwa. Strategiczne znaczenie gazociągów, w połączeniu z ich podatnością na uszkodzenia wywołane przez osuwiska, podkreśla konieczność przeprowadzania szczegółowych ocen geotechnicznych oraz zastosowania interdyscyplinarnego podejścia, obejmującego inżynierów, projektantów i specjalistów ds. środowiska. Pomimo trwających badań nad zachowaniem rurociągów w warunkach osuwiskowych, wciąż brakuje praktycznych narzędzi umożliwiających skuteczne przewidywanie i zapobieganie takim uszkodzeniom. W artykule omówiono kluczowe czynniki naturalne i antropogeniczne wywołujące osuwiska oraz podkreślono rosnącą rolę modelowania numerycznego w analizie pracy rurociągów w różnych scenariuszach osuwiskowych. Szczególną uwagę poświęcono zachowaniu stalowego rurociągu w strefie zmiany średnicy zlokalizowanej w obrębie obszaru osuwiskowego. Udoskonalanie systemów monitoringu oraz rozwój wskaźników prognostycznych są kluczowe dla ograniczania ryzyka i zwiększenia skuteczności działań awaryjnych w rejonach zagrożonych ruchami masowymi.

13

Analytical and numerical modeling of shallow water flow in a channel: Theoretical approaches and simulations

Bacharou Taofic, Sabi Takou Daniel, Adetola Jamal

International Journal of Applied Mechanics and Engineering

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2025

|

Vol. 30, no. 2

31--45

EN

This study focuses on the modeling and simulation of shallow water flows in a channel through the application of the Saint-Venant equations. Two main approaches were explored: an analytical solution and a numerical method based on finite difference discretization. The analytical solution provides exact expressions for water depth and velocity under simplified conditions, offering a reference point for validating numerical simulations. The numerical method, on the other hand, captures more complex dynamics such as wave propagation and nonlinear interactions between sections of the channel. The simulations reveal an inverse relationship between water depth and flow velocity, confirming the validity of the governing equations. Moreover, the influence of parameters such as channel slope, flow rate, and boundary conditions on the system?s dynamics is clearly illustrated. The comparative analysis of the two approaches shows that the finite difference method is a powerful tool for practical applications in hydraulic engineering, allowing for the accurate modeling of real-world phenomena while offering greater flexibility compared to idealized analytical solutions.

14

Wybrane aspekty modelowania pracy modułów wytwarzania energii – wymogi i realizacja

Komarzyniec Marek, Piekarski Grzegorz

Energetyka

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2025

|

nr 9

497--502

PL

W artykule przedstawiono aktualne wymagania i standardy dotyczące modelowania systemów elektroenergetycznych w kontekście integracji odnawialnych źródeł energii (OZE) z siecią. Omówiono europejskie regulacje, w szczególności kodeks sieci NC RfG, które nakładają obowiązek dostarczania i walidacji modeli symulacyjnych nowych jednostek wytwórczych. Autorzy analizują zarówno modele dostarczane przez producentów, jak i modele ogólne zgodne z normą IEC 61400-27-1, wskazując na ich zastosowanie w środowisku DIgSILENT PowerFactory. Podkreślono znaczenie iteracyjnego procesu modelowania, obejmującego testowanie, porównanie z danymi pomiarowymi i korektę parametrów, jako kluczowego elementu zapewnienia niezawodności i bezpieczeństwa pracy systemu elektroenergetycznego.

EN

The article presents the current requirements and standards for modelling power systems in the context of integrating renewable energy sources (RES) into the grid. The European regulations, and in particular the Network Code on Requirements for Grid Connection of Generators (NC RfG), are discussed which set out the obligation to provide and validate simulation models of new power generating modules. The authors analyse both models provided by manufacturers and general models compliant with IEC 61400-27-1, indicating their use in the DIgSILENT PowerFactory environment. The article emphasizes the importance of iterative modelling process, including testing, comparison with the measured data and parameter correction, as a key element to ensure reliable and safe operation of the electric power system.

15

Evaluation of deformation inhomogeneity in multi-layered steel-titanium and steel-magnesium systems

Pabich Bartłomiej, Żurowski Bartłomiej, Kwiecień Marcin, Majta Janusz

Computer Methods in Materials Science

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2025

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Vol. 25, No. 2

17--25

EN

In the presented study, plastometric tests using channel die compression were employed to define the boundary conditions for numerical simulations of the deformation processes of heterogeneous multi-layer systems composed of microalloyed steel, titanium, or magnesium. Various configurations, conditions, and deformation schemes were applied, which were then replicated in numerical simulations. Rheological models were used in the studies which, through computer simulations, enabled the modeling of interactions between the incoherent components of the microstructure. The primary outcome of the conducted experimental studies and numerical simulations is the ability to assess the heterogeneity of the studied multi-layer systems in terms of their mechanical states and influence on microstructural changes. This heterogeneity additionally arises from the diverse microstructural and rheological characteristics of the investigated materials (BCC vs. HCP), which, in turn, affect the strengthening mechanisms, primarily strain hardening. The results obtained from channel die compression tests were then used in simulations of multi-stage wire drawing, supporting both the design phase and the analysis of the resulting microstructural effects in the studied heterogeneous systems. It was observed that one of the key criteria for designing heterostructured wires from the examined materials is the proper selection of the volume fraction of the components, as well as the deformation history during multi-stage wire drawing, considering interpass heat treatment.

16

Damage Localization Using Fiber Bragg Grating Sensors in Self-referencing Conguration: A Numerical Study

Patange Abhishek, Moaf Farzam Omidi, Fiborek Piotr, Arumuganainar Adityan, Soman Rohan

Computer Assisted Methods in Engineering and Science

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2025

|

Vol. 32, no. 2

213--234

EN

This study investigates a self-referencing method for damage detection and localization using guided waves (GW) sensed by fiber Bragg grating (FBG) sensors. The research integrates advanced numerical simulations with an innovative configuration of sensors to enhance structural health monitoring (SHM). A self-referencing setup, employing FBG sensors with edge filtering method and remote bonding, enables a baseline-free damage detection approach. The methodology is validated as a proof-of-concept numerical model. The simulation framework incorporates a three-dimensional spectral element method for precise and efficient modelling of GW propagation and interactions with structural anomalies. Three different machine learning (ML) techniques are employed to detect and localize damages, demonstrating effectiveness of ML methods compared to traditional methods. The three techniques employed are decision tree, logistic model tree and random forest. Key findings highlight the effectiveness of random forest models in classifying damage states with a 98.67% accuracy. Different feature selection methods, are used to identify critical features. The proposed methodology reduces sensor requirements, lowers system complexity and cost, and enables efficient SHM solutions in extreme or large-scale environments. This work underscores the potential of ML techniques to perform detection and localization where traditional techniques fail.

17

Numerical simulation method of fork-flow condenser and the influence of fin structure characteristics

Liu Kaiming, Zhou Nianyong, Liu Lianghui, Han Benshi, Li Jing, Tang Guanghua, Liu Jixiang, Wang Feifei

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2025

|

Vol. 73, nr 4

art. no. e154273

EN

Many researchers have investigated numerical simulation methods for two-phase flow in condensers. Still, challenges persist due to these models’ large size, complex structure, and multiphase flow fields. To address these issues, this paper employs a periodic iterative numerical simulation approach for ultra-long condensers, validating the method through experiments and advancing the numerical simulation technology for such models. The study emphasizes the impact of structural changes on the refrigerant and air sides. Results indicate that the most minor error occurs when the number of iterations in the two-phase zone does not exceed three. Increasing the total number of refrigerant channels from 10 to 18 enhances heat transfer by 17.7% and condensation capacity by 10.6%. However, further increases in channel numbers lead to a significant rise in pressure drop, deteriorating heat transfer performance. Heat transfer and condensation capacity improve with the height-to-width ratio of the refrigerant channel, reaching optimal performance when the ratio is close to 1. Additionally, increasing the aspect ratio on the air side will improve the heat transfer and condensation rate of the condenser. However, when the aspect ratio reaches 4.53, further increases will lead to a decrease in the heat transfer coefficient and an increase in pressure drop.

18

Wind load equivalence method and structural response analysis of large-span space steel structures

Chen Yonggang, Ceng Jianming, Yu Zhiming, Wang Yukai, Gong Li, Yang Tengteng

Archives of Civil Engineering

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2025

|

Vol. 71, nr 2

313--330

EN

In coastal areas, large-span space steel net trusses experience structural deformation due to strong winds. Currently, the application of equivalent static wind load to the structure does not consider the influence of local forces. The local uneven force on the bars caused by the structural appearance is ignored, complicating the identification of local deformation in the net truss. Additionally, this simplification increases the difficulty in evaluating wind load-sensitive areas of the building. This paper introduces a novel method for calculating static equivalent wind load, considering the transmission relationship between the structural roofs appearance and the internal truss forces. Following the outlined methodology, wind load is precisely applied at nodes with diverse windward faces, taking into account the node area ratio. The paper also examines how varying standard wind load values affect mesh truss deformation under different wind angles. Results indicate that, at 0°, 90°, 180°, and 270° wind directions, wind load-sensitive areas are linked to roof shape and structural characteristics. Maximum displacement in the truss grid’s overall structure primarily occurs in the windward corner contact area. Network truss deformation linearly increases with the load standard. If the wind load exceeds 1.0 kN/m2, deformation is associated with the windward vertical plane’s area and steel column spacing, impacting overall structural safety.

19

Prediction of the sheet thickness effect on the formability of brass CuZn37 in single point incremental forming using Hooputra ductile damage model

Qate’a Marwa K., Mohammed Adnan I., Jweg Muhsin J.

Advances in Science and Technology. Research Journal

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2025

|

Vol. 19, no. 1

95--110

EN

Single point incremental Forming (SPIF) is a novel and practical approach for quickly prototyping and producing small batch sheet metal components. Predicting the impact of sheet thickness in the SPIF process is vital for assessing forming limits, understanding material behavior, optimizing tool design and path, and improving material utilization. It enables engineers to make informed decisions and optimize the process for enhanced formability and part quality. In this work, the numerical simulation of formability of the hyperbolic truncated pyramid with varying wall angles from 20° to 80° by the implementation of the “Hooputra Ductile Damage (HDD) model” in Abaqus/Explicit with the version of (CAE, 2017) has been conducted for brass of CuZn37 to study and predict the impact of the material's sheet thickness on its formability in SPIF process. In addition to that, the effect of sheet thickness on three other output responses: Von Mises stress, equivalent plastic strain, and contact pressure, have been examined. The results demonstrated the excellent success of the Hooputra Ductile Damage model in simulating the formability and capturing the fracture in the SPIF process with a total error ratio of approximately 1.91%. The results also showed that increasing sheet thickness from 0.4 – 1.4 mm increases formability, Von Mises stress, and contact pressure while leading to decreases and then increases the equivalent plastic strain.

20

Ductile iron crossbeam integrated parts casting process and shrinkage analysis

Heng Li, Wang Guo, Yongzheng Zhao, Weiguang Zhang, Yucheng Wu

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 5

422--429

EN

A composite component has been developed to replace the conventional multi-part crossmember assembly, with its sand casting technique optimized for truck chassis. Computational modeling and experimental methods are employed to simulate the sand casting process, focusing on filling, solidification, temperature distribution, liquid phase dispersion, and shrinkage. The study also fine-tunes the quantity and placement of risers. To minimize defects, the casting parameters are set as follows: pouring temperature of 1380°C, pouring speed of 10 cm/s, and mold preheating temperature of 20°C. This optimized process resulted in a 9.36% reduction in shrinkage compared to the original design. Experimental results indicate that the castings exhibit a spheroidization grade of 2, pearlite content ≥90%, tensile strength ≥854 MPa, elongation ≥6%, and are free from cracks and shrinkage in the critical load-bearing sections, thus meeting the required application standards.