Engineering Transactions
type: channel
description: Engineering Transactions (formerly Rozprawy Inżynierskie) is a refereed international journal founded in 1952. The journal promotes research and practice in engineering science and provides a forum for interdisciplinary publications combining mechanics with: Material science, Mechatronics, Biomechanics and Biotechnologies, Environmental science, Photonics, Information technologies, Other engineering applications. The journal publishes original papers covering a broad area of research activities including: Experimental and hybrid techniques, Analytical and numerical approaches. Review articles and special issues are also welcome. Following long tradition, all articles are peer reviewed and our expert referees ensure that the papers accepted for publication comply with high scientific standards. Engineering Transactions is a quarterly journal intended to be interesting and useful for the researchers and practitioners in academic and industrial communities. Occasionally, special issues of the journal may be devoted to publication of all or selected papers presented at international conferences or other scientific meetings. However, all papers intended for such an issue are subjected to the usual reviewing and acceptance procedure.
publisher: Institute of Fundamental Technological Research Polish Academy of Sciences
language: en
publication name: Engineering Transactions
issn: 0867-888X
copyright: Copyright on any open access article in the Engineering Transactions published by Polish Academy of Sciences and Institute of Fundamental Technological Research Polish Acoustical Society is retained by the author(s). Authors grant Institute of Fundamental Technological Research Polish Academy of Sciences a license to publish the article and identify itself as the original publisher. Authors also grant any user the right to use the article freely as long as its integrity is maintained and its original authors, citation details and publisher are identified. The Creative Commons Attribution License-ShareAlike 4.0 formalizes these and other terms and conditions of publishing articles. Exceptions to copyright policy For the articles which were previously published, before year 2019, policies that are different from the above. In all such, access to these articles is free from fees or any other access restrictions. Permissions for the use of the texts published in that journal may be sought directly from the Editorial Office of Engineering Transactions .
items: Preface
items: Analysis of a Variable Geometry Radial Inflow Turbine Using 1D Mean-line Model
items: Performance of a Hybrid Ichthyoid-Waterjet Articulated Propulsor
items: Analysis of the Braking Process for Curvilinear Motion of Vehicle
items: Energy Efficiency of an LPG-Powered Extended-Range Electric Vehicle
items: Determination of Operating Conditions of a Probe Block Designed for Fault Diagnostics in Rail Heads
items: The Development Features and Design of a Vibratory Gyroscope with a Metallic Cylindrical Resonator
items: Dynamic Eccentricity Modeling of a Switched Reluctance Motor
items: Comparison of Gantry Drive and Crankset: A Pilot Study Across a Broad Power Spectrum
items: Prediction of Soil Liquefaction Using Machine Learning Approaches
items: Effect of Initial Scratch on Ship Bottom Plate Corrosion Rate and Structural Crashworthiness in Grounding Incidents
items: Multi-Objective Design of a Pneumatic Adaptive Impact Absorber
items: Assessment of Methods for Determining Vehicle Emission Characteristics
items: The Development of Green Polylactic Acid (PLA)Composites for Wastewater Treatment – A Review
items: Research on Liquid Flow Resistance in Flow and Centrifugal Extraction Reactors
items: Effect of Turbulent Oil Film on the Dynamic Characteristics of 2-lobe Journal Bearings
items: Impact of Spin Slip Conditions on the Axisymmetric Rotation of a Spherical Particle in a Couple Stress Fluid Within a Cavity
items: Numerical and Experimental Analysis of Tuning Three Selected Types of Acoustic Helicoidal Resonators with 90-Degree Duct Elbow
items: A Concept of a Vision System for Position DeterminationUsing Spatial-Time-Frequency Analysis
items: Assessment of GFRP Reinforcement Bars Condition Based on Elastic Wave Propagation
items: Performance Evaluation of the Optimized Design Ratio Between the Diameters of the Basin and Curved Blade in the Gravitational Water Vortex Turbine
items: Simulation of an Anti-Lock Braking System in a MATLAB/Simulink Environment for Various Road Adhesion Properties
items: The Effect of Vocal Effort on Voice Quality in Occupations with High Vocal Load
items: A Comprehensive Review on the Applications of Nanometal Additives in Fuels for Internal Combustion Engines
items: Comparative Study of Matrix Methods for Modeling the Dispersive Character of Ultrasonic Guided Waves
items: Strength Estimation of Teeth Reinforced with Different Types of Post Systems
items: Investigation of a Vibratory Stress Relief System for Hard-Turned EN 31 Components
items: Modeling of the Acoustic Properties of Foamed Polypropylene Panels
items: Investigating the Mechanical, Physical and Biological Properties of PMMA/TiO2 Composites with Nanoclay for Denture Applications
items: Enhancement of the Thermal Stability of Engine Block Alloy Al-10Si-1Cu-0.5Mg-0.5Ni-0.5Fe with Trace Additions of Ti and Zr

Preface
type: item
description: Preface to a selection of papers presented at the SiMRTRANS Scientific and Technical Conference: “Innovative Solutions in Transport”, which took place at the Warsaw University of Technology, Faculty of Automotive and Construction Machinery Engineering, on September 19, 2024.
subject: SIMRTRANS: Innovative solutions in means of transport
  topic: section
creator: Dariusz WIĘCKOWSKI
rights: Copyright (c) 2025 Dariusz WIĘCKOWSKI https://creativecommons.org/licenses/by/4.0
date: 2025-09-24
publication date: 2025-09-24
starting page: 325
ending page: 325
doi: 10.24423/engtrans.3603.2025

Analysis of a Variable Geometry Radial Inflow Turbine Using 1D Mean-line Model
type: item
description: Despite great progress in 3D computational fluid dynamics (CFD), mathematical modeling used for turbomachinery analysis, the prediction of flow parameters in the rotor (impeller) of radial inflow turbines using existing turbulence models often yields unsatisfactory results. This is because real physical processes related to turbulence are very complex. Other limitations of CFD tools include numerical errors due to finite difference approximations. Thus, for the analysis and optimization of radial inflow turbines, empirical loss correlations applied to a mean-line 1D mathematical model can provide faster and more accurate results compared to CFD simulations. In this study, a 1D approach was used for the mathematical modeling of gas flow in a variable geometry radial inflow turbine with a vaneless volute distributor (VVD). The variable geometry turbine (VGT) was part of a turbocharging system. Combustion engine operation mode with high-power and low-crankshaft rotational speed was chosen, as engine performance under this condition is sensitive to turbocharger adjustment in terms of break specific fuel consumption (BSFC) and other critical parameters. An experimentally-based approach was used where gas flow characteristics in the VGT were calculated under real engine-turbocharger operating conditions. Accordingly, exhaust gas parameters were first measured on an experimental setup. Mathematical modeling then allowed to assess how adjustment in VGT influenced turbine indices, including loss distribution across the stage. It was also validated in this study that during high-load and low-crankshaft operating conditions of the compression ignition (CI) engine, it is recommended to minimize the cross-sectional area at the outlet of the volute acceleration section in the VGT. This adjustment results in better fuel efficiency and lower thermal loads on turbine components, despite a slight reduction in the turbine’s overall efficiency.
subject: SIMRTRANS: Innovative solutions in means of transport
  topic: section
subject: mathematical modelling
  topic: keywords
subject: radial inflow turbine
  topic: keywords
subject: variable geometry
  topic: keywords
subject: loss analysis
  topic: keywords
creator: Dmytro SAMOILENKO
rights: Copyright (c) 2025 Dmytro SAMOILENKO https://creativecommons.org/licenses/by/4.0
date: 2025-09-24
publication date: 2025-09-24
starting page: 463
ending page: 483
doi: 10.24423/engtrans.3498.2025

Performance of a Hybrid Ichthyoid-Waterjet Articulated Propulsor
type: item
description: The concept of a bioinspired ichthyoid-waterjet propulsor for autonomous underwater vehicles (AUVs) is investigated. The propulsor consists of an articulated fluid-conveying pipe with a propulsive fin at the end. Water drawn into the hull is accelerated to a supercritical velocity, which yields flutter vibrations of the propulsor resembling the motion of a swimming fish. The fin acts on the surrounding water and generates thrust. At the same time, the ejected water produces recoil. Using the proposed dynamical model, three types of propulsors for different swimming speeds are investigated. At low swimming speeds, the propulsive force generated by the propulsors can be up to 30% higher than the thrust of a conventional waterjet propulsor with the same physical parameters. However, this advantage in the generated thrust decreases with the swimming speed increase. The results are obtained by analyzing the approximation of the bifurcating solution and numerical simulations of the differential equation governing the dynamics.
subject: Research Papers
  topic: section
subject: autonomous underwater vehicle
  topic: keywords
subject: waterjet propulsion
  topic: keywords
subject: fish swimming
  topic: keywords
subject: flutter
  topic: keywords
subject: fluid-conveying pipe
  topic: keywords
creator: Tomasz SZMIDT
rights: Copyright (c) 2025 Tomasz SZMIDT https://creativecommons.org/licenses/by/4.0
date: 2025-10-16
publication date: 2025-10-16
doi: 10.24423/engtrans.3593.2025

Analysis of the Braking Process for Curvilinear Motion of Vehicle
type: item
description: Road incident reconstruction frequently includes the possibility of avoiding a collision. To perform such analysis, it is necessary to compare the available distance with the minimum braking distance. Therefore, to avoid a collision, the braking distance must be shorter than the available distance. The braking distance depends on parameters such as tyre-to-road adhesion coefficient, the initial velocity of a vehicle, the driver’s reaction time and the time needed to reach full braking force. However, the problem is that, in practice, none of these values are known during traffic incident reconstruction. As a result, the estimated vehicle velocity is uncertain. This is due to the method used to reconstruct a road incident (and the errors in the evidence data). The tyre-to-road adhesion coefficient depends on many factors and can be estimated with limited accuracy, usually ±0.1. The uncertainty of the estimate is approximately ±15%. The reaction time of a specific driver under the conditions present during a road incident is not precisely known. Therefore, an average value for most drivers is taken into account. It is assumed that a healthy driver’s reaction time should not exceed this value, and a longer reaction time is associated with incorrect driving behavior. The time taken to reach full braking force in a real situation is also unknown. Usually, average values are taken from the literature, without the analysis of a technical condition of a vehicle. This article considers the mechanics of vehicle braking, taking into account the action of lateral forces on this vehicle while considering a curved track. The maximum deceleration during braking is determined analytically, and a condition is formulated to indicate whether it is justified to use an advanced computational model instead of the basic one described in the literature. The analysis includes some dimensionless parameters describing the position of the center of gravity, tangential forces between the tyre a…
subject: Research Papers
  topic: section
subject: active safety
  topic: keywords
subject: braking on the road arc
  topic: keywords
subject: braking force
  topic: keywords
subject: driver reaction time
  topic: keywords
subject: intensity of turning
  topic: keywords
creator: Piotr FUNDOWICZ
creator: Hubert SAR
creator: Mateusz BRUKALSKI
creator: Michał ABRAMOWSKI
rights: Copyright (c) 2025 Piotr FUNDOWICZ, Hubert SAR, Mateusz BRUKALSKI, Michał ABRAMOWSKI https://creativecommons.org/licenses/by/4.0
date: 2025-11-06
publication date: 2025-11-06
doi: 10.24423/engtrans.3489.2025

Energy Efficiency of an LPG-Powered Extended-Range Electric Vehicle
type: item
description: This paper deals with energy efficiency evaluation of an extended range electric vehicle (EREV) equipped with a range extender (REX) powered by liquefied petroleum gas (LPG). The investigation is based on simulation, with key input data derived from empirical studies carried out by the authors. It includes four target driving ranges (200, 300, 400, 500 km), six driving cycles (WLTC 3b, FTP-75, CLTC-P, Artemis 130, NYCC, HWFET) and three battery size variants for the WLTC 3b cycle. The influence of the these factors on the overall efficiency and specific energy consumption of the EREV is assessed. The results are analyzed in terms of the number of REX activations per 100 km and the total REX operating time.
subject: SIMRTRANS: Innovative solutions in means of transport
  topic: section
subject: extended-range electric vehicle
  topic: keywords
subject: efficiency
  topic: keywords
subject: energy consumption
  topic: keywords
subject: LPG
  topic: keywords
creator: Paweł KRAWCZYK
creator: Artur KOPCZYŃSKI
creator: Jakub LASOCKI
rights: Copyright (c) 2025 Paweł KRAWCZYK, Artur KOPCZYŃSKI, Jakub LASOCKI https://creativecommons.org/licenses/by/4.0
date: 2025-09-24
publication date: 2025-09-24
starting page: 421
ending page: 440
doi: 10.24423/engtrans.3490.2025

Determination of Operating Conditions of a Probe Block Designed for Fault Diagnostics in Rail Heads
type: item
description: In this paper, the key parameters influencing the proper operation of ultrasonic probes for railway rails diagnostics are determined. The goal is to test a set of ultrasonic probes under conditions occurring at high diagnostic speeds. Four issues are studied in more detail. The probe block-rail contact force required to obtain maximum echo level is determined. In the authors’ opinion, the key aspect is the design of the water irrigation nozzle shape in order to produce a laminar couplant flow under the probes. The dependence of the amplitude of the recorded echo on the coupling layer thickness is experimentally investigated. The population of registered signal samples is processed to determine the testing speed limit, which resulted from the loss of data validation ability. The speed limit is calculated based on the average value of the amplitude of the measured signal and the standard deviation of the registered population of amplitudes. The conducted research allows the authors to conclude that the instrumentation they developed enables the recording of an ultrasonic signal propagating through the tested rail at scanning speed of up to 100 km/h.
subject: Research Papers
  topic: section
subject: railway rails diagnostics
  topic: keywords
subject: ultrasonic examination
  topic: keywords
subject: ultrasonic probe-rail interface
  topic: keywords
creator: Zbigniew RANACHOWSKI
creator: Sławomir MACKIEWICZ
creator: Tomasz KATZ
creator: Tomasz DĘBOWSKI
creator: Grzegorz STARZYŃSKI
creator: Marcin LEWANDOWSKI
creator: Łukasz ANTOLIK
rights: Copyright (c) 2025 Zbigniew RANACHOWSKI, Sławomir MACKIEWICZ, Tomasz KATZ, Tomasz DĘBOWSKI, Grzegorz STARZYŃSKI, Marcin LEWANDOWSKI, Łukasz ANTOLIK https://creativecommons.org/licenses/by/4.0
date: 2025-10-17
publication date: 2025-10-17
doi: 10.24423/engtrans.3522.2025

The Development Features and Design of a Vibratory Gyroscope with a Metallic Cylindrical Resonator
type: item
description: This paper presents the results of developing a vibratory gyroscope with a cylindrical resonator made of Elinvar alloy. The vibratory gyroscope operates in three modes. These modes include rate mode, rate-integrating mode, and a new, third, differential mode. The differential mode can simultaneously measure two opposite angular rates, Ω and −Ω. A block diagram of the standing wave control system for each mode is presented. The advantages and disadvantages of each of the modes are analyzed. A triple-mode gyro is proposed. The results of experimental studies and simulation data are also presented.
subject: Research Papers
  topic: section
subject: vibratory gyroscope
  topic: keywords
subject: standing wave
  topic: keywords
subject: control system
  topic: keywords
subject: auto-compensation
  topic: keywords
creator: Valerii CHIKOVANI
creator: Serhii HOLOVACH
creator: Hryhorii STROKACH
creator: Vadym AVRUTOV
rights: Copyright (c) 2025 Valerii CHIKOVANI, Serhii HOLOVACH, Hryhorii STROKACH, Vadym AVRUTOV https://creativecommons.org/licenses/by/4.0
date: 2025-06-26
publication date: 2025-06-26
starting page: 279
ending page: 304
doi: 10.24423/engtrans.3458.2025

Dynamic Eccentricity Modeling of a Switched Reluctance Motor
type: item
description: The switched reluctance motor (SRM), known for its robust and simple construction, is widely utilized in critical applications. This study investigates the impact of rotor dynamic eccentricity on the motor's current signal. Our research introduces a straightforward diagnostic method to detect and quantify dynamic eccentricity by analyzing the current signal spectrum. This approach specifically focuses on identifying amplitude increases in characteristic additional harmonics, leveraging fundamental electromagnetic transformations to eliminate the need for complex algorithms. Through coupled computer simulations, combining a finite element analysis model (FEMM) with dynamic equation solutions in Simulink, this study identifies specific eccentricity ranges and their corresponding characteristic current values, offering a reliable tool for SRM condition monitoring.
subject: SIMRTRANS: Innovative solutions in means of transport
  topic: section
subject: switched reluctance motor
  topic: keywords
subject: SRM
  topic: keywords
subject: motor diagnostics
  topic: keywords
subject: eccentricity
  topic: keywords
creator: Jakub LORENCKI
creator: Adrian CHMIELEWSKI
rights: Copyright (c) 2025 Jakub LORENCKI, Adrian CHMIELEWSKI https://creativecommons.org/licenses/by/4.0
date: 2025-09-24
publication date: 2025-09-24
starting page: 441
ending page: 461
doi: 10.24423/engtrans.3518.2025

Comparison of Gantry Drive and Crankset: A Pilot Study Across a Broad Power Spectrum
type: item
description: The gantry drive was originally invented in 1948 in England and was “rediscovered” in Poland in 2019 while working on lightweight, personal, compact vehicles. In this study, the gantry drive is subjected to dynamic tests against the background of the commonly known crankset. The aim of the dynamic tests is to develop power curves and measure efficiency for various human-mechanism systems, i.e., the hand-driven crankset, the leg-driven crankset, and the gantry drive. Pilot dynamic tests have shown many advantages of the gantry over the crankset; in general, test participants were much less tired when using the gantry drive.
subject: SolMech 2024
  topic: section
subject: gantry
  topic: keywords
subject: crankset
  topic: keywords
subject: drive
  topic: keywords
subject: power
  topic: keywords
subject: vehicle
  topic: keywords
creator: Łukasz BEREŚ
creator: Marcin OBSZAŃSKI
creator: Paweł PYRZANOWSKI
rights: Copyright (c) 2025 Łukasz BEREŚ, Marcin OBSZAŃSKI, Paweł PYRZANOWSKI https://creativecommons.org/licenses/by/4.0
date: 2025-12-03
publication date: 2025-12-03
doi: 10.24423/engtrans.3485.2025

Prediction of Soil Liquefaction Using Machine Learning Approaches
type: item
description: In the geotechnical engineering field, the assessment of liquefaction potential is a critical aspect of site evaluation. This work focuses on the application of support vector machines (SVM) to improve the accuracy of liquefaction potential evaluation. Input data were collected from the authors' previous study and include parameters such as groundwater table (GWT), depth, fineness content, peak ground acceleration (PGA), corrected SPT-N value, total stress, and effective overburden stress. Radial basis function (RBF), linear, polynomial, and sigmoid are the four SVM kernel functions that are examined in this study to model liquefaction-related data using three approaches: grid search cross-validation, k-fold cross-validation, and fuzzy c-clustering means (FCM). Several performance metrics, including accuracy, precision, recall, and the area under the receiver operating characteristics (ROC) curve (AUC), among others, are used to evaluate the developed machine learning (ML) models. The linear and polynomial functions, for the grid search cross-validation approach, show higher performance with an accuracy of 94.64%, recall of 95.55%, F1-score of 96.63, and AUC of 0.99 on the testing data. For the k-fold partitioning approach, the RBF yields higher performance metrics compared to the other three functions, with an accuracy of 92.73%, precision of100%, F1-score of 95.0%, and AUC of 0.98. In the FCM technique, the linear and polynomial kernels again yield greater accuracy, precision, F1-score, and specificity, while, the AUC values of the sigmoid and RBF kernels are higher. The current analysis recommends the RBF over other mathematical functions based on the k-fold partitioning technique after evaluating all performance matrices.
subject: Research Papers
  topic: section
subject: liquefaction
  topic: keywords
subject: support vector machine
  topic: keywords
subject: mathematical functions
  topic: keywords
subject: divisional approaches
  topic: keywords
subject: performance metricsfunctions
  topic: keywords
subject: performance metrics
  topic: keywords
creator: Md. Mahabub RAHMAN
creator: Md. Belal HOSSAIN
creator: Abu SAYED
rights: Copyright (c) 2025 Md. Mahabub RAHMAN, Md. Belal HOSSAIN, Abu SAYED https://creativecommons.org/licenses/by/4.0
date: 2025-06-26
publication date: 2025-06-26
starting page: 257
ending page: 277
doi: 10.24423/engtrans.3360.2025

Effect of Initial Scratch on Ship Bottom Plate Corrosion Rate and Structural Crashworthiness in Grounding Incidents
type: item
description: Hitting an object in the ocean can peel off the coating on a ship's plate. The exposed plate can be vulnerable to corrosion because it is exposed to the environment and seawater, which can degrade its strength. So, the crashworthiness of the bottom plate should be evaluated in the event of a grounding incident. The ratio of the scratch area and the number of stripes are used as experimental variables. Based on seawater corrosion experiments, the plate's corrosion rate increases quadratically with the scratch area, which is then used for grounding simulations. Eighteen grounding scenarios, based on scratch size, dimensions, and corrosion exposure, reveal that only two or three stripes significantly reduce the plate’s strength in simulations. In addition, in the case of two or three stripes of scratches, corrosion further reduces the plate’s strength in the grounding simulations. This plate has limited space in the vertical direction, which influences the horizontal stripe of scratches and affects the plate's strength in grounding simulation, as compared to the vertical stripes. Besides this, the pattern of crack propagation depends on the reaction force.
subject: Research Papers
  topic: section
subject: scratch
  topic: keywords
subject: ship grounding
  topic: keywords
subject: severe corrosion
  topic: keywords
subject: finite element analysis
  topic: keywords
creator: Ocid MURSID
creator: Dean Nadhif ALFARIS
creator: Tuswan TUSWAN
creator: Ahmad Fauzan ZAKKI
creator: Aulia WINDYANDARI
creator: Karno R. MALAU
creator: Haris NUBLI
rights: Copyright (c) 2025 Ocid MURSID, Dean Nadhif ALFARIS, Tuswan TUSWAN, Ahmad Fauzan ZAKKI, Aulia WINDYANDARI, Karno R. MALAU, Haris NUBLI https://creativecommons.org/licenses/by/4.0
date: 2025-06-26
publication date: 2025-06-26
starting page: 233
ending page: 256
doi: 10.24423/engtrans.3434.2025

Multi-Objective Design of a Pneumatic Adaptive Impact Absorber
type: item
description: This manuscript proposes a multicriteria approach to the design optimization of adaptive pneumatic impact absorbers. The considered absorber consists of two sealed chambers separated by a piston with an internal valve. Proper valve control affects gas flow between the chambers and ensures a flat reaction force profile over a possibly long piston stroke. The design of such an absorber is defined by three parameters: initial gas pressure, diameter, and length. For a given range of impact conditions, the worst-case maximum deceleration and maximum mass flow rate are used as design criteria in a multicriterial minimization problem. Solutions to this problem provide an optimal balance between impact absorption performance and the technical requirements the valve must meet. An example is considered, which illustrates the Pareto-optimal solutions in the design space and the complex interdependency between initial pressure and absorber diameter at each absorber length. The results demonstrate that a proper choice of design parameters can result in significant performance improvements.
subject: Research Papers
  topic: section
subject: adaptive pneumatic absorbers
  topic: keywords
subject: impact absorption
  topic: keywords
subject: design optimization
  topic: keywords
subject: multi-objective optimization
  topic: keywords
subject: mass flow rate
  topic: keywords
creator: Rafal WISZOWATY
creator: Cezary GRACZYKOWSKI
creator: Grzegorz MIKUŁOWSKI
creator: Jan HOLNICKI-SZULC
creator: Zbigniew WOŁEJSZA
creator: Anita ORŁOWSKA-GAŁĘZIA
creator: Łukasz JANKOWSKI
rights: Copyright (c) 2025 Rafal WISZOWATY, Cezary GRACZYKOWSKI, Grzegorz MIKUŁOWSKI, Jan HOLNICKI-SZULC, Zbigniew WOŁEJSZA, Anita ORŁOWSKA-GAŁĘZIA, Łukasz JANKOWSKI https://creativecommons.org/licenses/by/4.0
date: 2025-10-02
publication date: 2025-10-02
doi: 10.24423/engtrans.3546.2025

Assessment of Methods for Determining Vehicle Emission Characteristics
type: item
description: This paper presents an analysis of pollutant emissions (carbon monoxide, hydrocarbons, nitrogen oxides, methane, non-methane volatile organic compounds and carbon dioxide) from a passenger car, particularly under real-world driving conditions, to more accurately model the impact of transport on the environment. These pollutants were selected due to their regulatory relevance and significant environmental and health impacts. A mathematical model developed in this study was used to estimate emissions, with vehicle speed identified as a key parameter influencing emission levels. Various speed ranges and their impact on emission levels were considered during parametric identification. Since the relationship between pollutants and speed is nonlinear, the least squares method was applied to estimate model parameters for the different pollutants. The model developed in the paper allows for precise emission prediction for various vehicle use scenarios. The scenarios analyzed include urban driving conditions with vehicle speeds not exceeding 60 km/h. The selected speed profile was first recorded in real-world traffic using a portable emissions measurement system (PEMS) and subsequently reproduced on a chassis dynamometer to ensure test repeatability under controlled laboratory conditions.
subject: SIMRTRANS: Innovative solutions in means of transport
  topic: section
subject: pollutant emissions
  topic: keywords
subject: emission modeling
  topic: keywords
subject: road emissions
  topic: keywords
subject: parametric estimation
  topic: keywords
creator: Piotr LASKOWSKI
creator: Edward KOZŁOWSKI
creator: Magdalena ZIMAKOWSKA-LASKOWSKA
creator: Piotr WIŚNIOWSKI
rights: Copyright (c) 2025 Piotr LASKOWSKI, Edward KOZŁOWSKI, Magdalena ZIMAKOWSKA-LASKOWSKA, Piotr WIŚNIOWSKI https://creativecommons.org/licenses/by/4.0
date: 2025-09-24
publication date: 2025-09-24
starting page: 407
ending page: 420
doi: 10.24423/engtrans.3494.2025

The Development of Green Polylactic Acid (PLA)Composites for Wastewater Treatment – A Review
type: item
description: Polylactic acid (PLA) is a biodegradable polyester derived from renewable resources, recognized for its environmental sustainability and versatile properties. Its applications spam the biomedical, textile, and packaging industries and, more recently, wastewater treatment. This review explores recent advancements in the use of PLA and its composites for wastewater treatment, emphasizing their effectiveness, modification techniques to enhance performance, and future research directions. A thorough literature review was conducted, covering the past decade studies, and, including research articles, reviews, and case studies on PLA’s application in wastewater treatment and comparative performance against other adsorbents. Although PLA’s natural adsorption capacity is limited, it has demonstrated significant potential for removing contaminants such as heavy metals, organic dyes, and other organic pollutants. Various modifications, including surface chemical changes, physical blending with nanomaterials, and more, have notably improved its adsorption performance. Modified PLA composites thus present a viable and sustainable solution for wastewater treatment. Continued research is essential to further optimize these modifications, explore novel composite materials, develop scalable technologies, and assess long-term environmental impacts. This review offers a critical synthesis of current knowledge on PLA-based materials in wastewater treatment, aiming to inform and guide future research in sustainable water purification technologies.
subject: Review Papers
  topic: section
subject: polylactic acid
  topic: keywords
subject: PLA
  topic: keywords
subject: wastewater treatment
  topic: keywords
subject: adsorbents
  topic: keywords
subject: adsorption
  topic: keywords
subject: PLA composites
  topic: keywords
subject: environmental sustainability
  topic: keywords
creator: Andriy Anta KACARIBU
creator: Yuliani AISYAH
creator: Febriani FEBRIANI
creator: Darwin DARWIN
rights: Copyright (c) 2022 Andriy Anta KACARIBU, Yuliani AISYAH, Febriani FEBRIANI, Darwin DARWIN https://creativecommons.org/licenses/by/4.0
date: 2025-09-24
publication date: 2025-09-24
starting page: 485
ending page: 524
doi: 10.24423/engtrans.3534.2025

Research on Liquid Flow Resistance in Flow and Centrifugal Extraction Reactors
type: item
description: This paper presents research that formed the basis for the development of a low-temperature centrifugal extraction reactor. This reactor is used to obtain medicinal substances from herbs, where key parameters include extraction time, temperature, and the velocity of the solvent that flows through the dried herbs. An important parameter for performing simulation studies was the assessment of the medium flow characteristics through the dried medicinal herb material. For this purpose, a flow reactor was developed and tested. The first part of the paper discusses the results of numerical and experimental studies on liquid flow through the extraction reactor. This part of the work was carried out in order to determine the parameters related to the resistance of liquid flow through dried medicinal herbs. This resistance of the liquid flow through the herbs affects the limitation of its velocity and has a direct impact on the efficiency of the process. In the second part of the paper, the results obtained from the flow reactor experiments were used for numerical investigations of the centrifugal extractor drum.
subject: SIMRTRANS: Innovative solutions in means of transport
  topic: section
subject: extraction reactor
  topic: keywords
subject: numerical investigations
  topic: keywords
subject: flow resistance
  topic: keywords
subject: medicinal herbs
  topic: keywords
creator: Jędrzej MĄCZAK
creator: Dmytro SAMOILENKO
creator: Michal MAKOWSKI
creator: Lech KNAP
rights: Copyright (c) 2025 Jędrzej MĄCZAK, Dmytro SAMOILENKO, Michal MAKOWSKI, Lech KNAP https://creativecommons.org/licenses/by/4.0
date: 2025-09-24
publication date: 2025-09-24
starting page: 387
ending page: 405
doi: 10.24423/engtrans.3471.2025

Effect of Turbulent Oil Film on the Dynamic Characteristics of 2-lobe Journal Bearings
type: item
description: Turbogenerators in power plants utilize two-lobe journal bearings, which can carry large loads with good stability at the speeds typically encountered in the power industry. These bearings feature the profiles such as elliptical, offset, cylindrical or pericycloidal. The design of these bearings ensures proper load capacity, favorable thermal conditions for the oil film, and stable operation of the associated turbounits. However, the design of these bearings should be supported by calculations that account for turbulence generated in the oil film. This paper presents the results of dynamic characteristic calculations for four types of two-lobe journal bearings operating under adiabatic laminar or turbulent flow conditions in the lubricating gap. The dynamic characteristics, expressed as the stiffness and damping coefficients of the oil film, were obtained using the perturbation method. Stability ranges for a simple symmetric rotor were determined for the considered bearings. A numerical algorithm for the iterative solution of the Reynolds, energy and viscosity equations was employed to calculate the oil film forces, which formed the basis for the bearing’s dynamic characteristics. These investigations were carried out assuming the static equilibrium position of the journal.
subject: Research Papers
  topic: section
subject: multilobe journal bearing
  topic: keywords
subject: turbulent oil film
  topic: keywords
subject: dynamic characteristics
  topic: keywords
subject: rotor stability
  topic: keywords
creator: Stanislaw Kazimierz STRZELECKI
rights: Copyright (c) 2025 Stanislaw Kazimierz STRZELECKI https://creativecommons.org/licenses/by/4.0
date: 2025-06-26
publication date: 2025-06-26
starting page: 219
ending page: 232
doi: 10.24423/engtrans.3475.2025

Impact of Spin Slip Conditions on the Axisymmetric Rotation of a Spherical Particle in a Couple Stress Fluid Within a Cavity
type: item
description: This paper investigates the effect of spin slip condition on the flow of a couple stress fluid between two concentric spheres. The spherical particles rotate about the z-axis with different angular velocities and under the assumption of low Reynolds numbers. To solve the governing equations, we impose tangential slip and couple stress spin slip boundary conditions at the surfaces of the particle and the cavity wall. The nondimensional torque is computed, tabulated and graphically analyzed for various values of the separation parameter, couple stress viscosity, angular velocity ratio, tangential slip, and couple stress spin slip parameters. Our findings indicate that torque value increases with higher values of the couple stress viscosity parameter, separation parameter, tangential slip parameter, and spin slip parameter. However, the torque decreases as the angular velocity ratio increases. Furthermore, our results agree with previously published findings for cases with vanishing tangential slip and spin slip at the particle and cavity surfaces.
subject: Research Papers
  topic: section
subject: couple stress fluid
  topic: keywords
subject: spin slip effect
  topic: keywords
subject: rotation
  topic: keywords
subject: torque
  topic: keywords
subject: spherical particle
  topic: keywords
creator: Shekhar NISHAD
creator: Krishna Prasad MADASU
rights: Copyright (c) 2025 Shekhar NISHAD, Krishna Prasad MADASU https://creativecommons.org/licenses/by/4.0
date: 2025-06-26
publication date: 2025-06-26
starting page: 199
ending page: 218
doi: 10.24423/engtrans.3427.2025

Numerical and Experimental Analysis of Tuning Three Selected Types of Acoustic Helicoidal Resonators with 90-Degree Duct Elbow
type: item
description: This work presents the results of numerical and experimental analyses regarding the tuning of three selected acoustic helicoidal resonators using a 90-degree elbow in a cylindrical duct. The elbow is placed directly at the end of the resonators, which were additionally rotated about the duct axis at a specific angle (45° angle change in the numerical analysis and 90° angle change in the experiment). Three resonators with the same helicoid pitch-to-duct diameter ratio of s/d = 1.976 but with different numbers of turns n of 0.671, 0.695, and 1.0 were selected for analysis. They represent three different transmission loss (TL) characteristics in the frequency domain. In the considered system of helicoidal resonators and a 90-degree duct elbow, it was found that the selected resonators can be tuned by rotating them, effectively covering nearly the entire range of their characteristic sound attenuation resulting from acoustic resonance.
subject: OSA2024
  topic: section
subject: helicoidal resonator
  topic: keywords
subject: duct acoustics
  topic: keywords
subject: experiment
  topic: keywords
subject: numerical analysis
  topic: keywords
creator: Wojciech ŁAPKA
rights: Copyright (c) 2025 Wojciech ŁAPKA https://creativecommons.org/licenses/by/4.0
date: 2025-12-02
publication date: 2025-12-02
doi: 10.24423/engtrans.3377.2025

A Concept of a Vision System for Position DeterminationUsing Spatial-Time-Frequency Analysis
type: item
description: This paper presents the concept of a vision system designed to determine the position of a camera within a given coordinate system. The system focuses on identifying pulsating light markers in images recorded by the camera. These markers are characterized by specific colors, pulsation frequencies and known locations. Detection is achieved using a spatial-time-frequency processing method developed by the authors. The identified markers serve as input data for a mathematical model that determines the camera’s position within the reference system. The article discusses the theoretical foundations of the proposed system design. The system was subjected to testing to verify its operational accuracy and precision in position determination. The results of these tests are presented. The article concludes with a summary of the work and a discussion of the system’s further development and practical applications.
subject: SIMRTRANS: Innovative solutions in means of transport
  topic: section
subject: image processing
  topic: keywords
subject: spectrum analysis
  topic: keywords
subject: light markers
  topic: keywords
subject: localization
  topic: keywords
creator: Piotr MIŚ
creator: Przemysław SZULIM
creator: Jędrzej MĄCZAK
rights: Copyright (c) 2022 Piotr MIŚ, Przemysław SZULIM, Jędrzej MĄCZAK https://creativecommons.org/licenses/by/4.0
date: 2025-09-24
publication date: 2025-09-24
starting page: 367
ending page: 386
doi: 10.24423/engtrans.3499.2025

Assessment of GFRP Reinforcement Bars Condition Based on Elastic Wave Propagation
type: item
description: New technologies in construction constitute a crucial element of effective development. Contemporary trends have led to increasing interest in composite materials, mainly due to their unique properties. The flexibility in shaping composite materials enables the production of reinforcing bars, providing a viable alternative to the widely used steel bars. The implementation of innovative solutions necessitates monitoring the performance of structures. Using information on the propagation of elastic waves is one of the non-destructive testing (NDT) methods for observing the construction behavior. An effort to employ this technique in the assessment of the anchoring condition and stress evaluation in glass fiber-reinforced polymer (GFRP) bars is presented in this study. During laboratory testing, samples of ribbed bars with diameters of f6 mm, f10 mm, and f16 mm were used (a total of 20 bars). Measurements were performed using laser Doppler vibrometry and piezoelectric transducers (PZT). Elastic waves were excited using a PZT sensor attached to one end of the bar, and the wave propagation was recorded in three ways: using a PZT sensor at the opposite end of the bar, using LDV at the opposite end, and on the sidewall. The research included samples of bars without anchorage, bars with anchorages (used for placement in a strength-testing machine), and specimens subjected to tensile testing (according to ISO 10406-1:2015). The collected signals were compared in both the time and frequency domains, considering variations in wave propagation due to different diameters, anchoring methods, and stress states. Based on the obtained results, it can be concluded that the analysis of the elastic wave propagation holds potential for assessing the condition of GFRP reinforcing bars.
subject: SolMech 2024
  topic: section
subject: composite reinforcement
  topic: keywords
subject: GFRP bars
  topic: keywords
subject: elastic wave
  topic: keywords
subject: non-destructive testing
  topic: keywords
creator: Anna RZEPKA
creator: Dominika ZIAJA
creator: Michał JUREK
creator: Agnieszka WIATER
rights: Copyright (c) 2022 Anna RZEPKA, Dominika ZIAJA, Michał JUREK, Agnieszka WIATER https://creativecommons.org/licenses/by/4.0
date: 2025-07-10
publication date: 2025-07-10
doi: 10.24423/engtrans.3491.2025

Performance Evaluation of the Optimized Design Ratio Between the Diameters of the Basin and Curved Blade in the Gravitational Water Vortex Turbine
type: item
description: The key role of the gravitational water vortex turbine (GWVT) is to generate electricity to support modern civilization in their essential daily needs by harnessing kinetic energy from flowing water. With this, the lack of access to electricity can be addressed by utilizing the potential of the Philippines’ abundant bodies of water. This study evaluates the impact of low-density turbine blades on the GWVT with reference to the selected parameters: rotational speed and mechanical efficiency. The ANSYS simulation and laboratory test both found that the 0.55 ratio between the diameters of the nylon rod blade and the optimized basin with guide vanes achieved the highest rotational speed of 205.95 RPM and 120.1 RPM, respectively. Conversely, the design with a 0.60 ratio between the diameters of the steel blade and the normal basin provided optimum performance, achieving an average of 98.2 RPM and the highest mechanical efficiency of 43.75%, thereby preventing energy loss and maximizing output performance. Results also indicated a significant difference in the performance of the GWVT using the normal basin compared to the optimized basin with guide vanes. Lastly, there was a considerable difference in the performance of the GWVT for the design ratios of 0.55, 0.60, and 0.65 for the runner blade and basin, and further analysis showed that torque and rotational speed have a linear relationship. Thus, this study could serve as a benchmark for identifying alternative materials and optimizing the design of GWVT to help improve power generation using hydropower as a source of electricity.
subject: Research Papers
  topic: section
subject: gravitational water vortex turbine
  topic: keywords
subject: optimized basin
  topic: keywords
subject: normal basin
  topic: keywords
subject: steel turbine blade
  topic: keywords
subject: nylon rod turbine blade
  topic: keywords
creator: Christie Claire D. BOISER
creator: Lance Arthur Lim CARPIO
creator: Philip Jun S. CELERINOS
creator: Joven Dy S. LEE
creator: Gary G. PINILI
rights: Copyright (c) 2022 Christie Claire D. BOISER, Lance Arthur Lim CARPIO, Philip Jun S. CELERINOS, Joven Dy S. LEE, Gary G. PINILI https://creativecommons.org/licenses/by/4.0
date: 2025-07-22
publication date: 2025-07-22
doi: 10.24423/engtrans.3459.2025

Simulation of an Anti-Lock Braking System in a MATLAB/Simulink Environment for Various Road Adhesion Properties
type: item
description: Driving safety is very important to every vehicle user. Automobile manufacturers compete by introducing increasingly advanced safety systems, which, when combined with appropriate driver response, help prevent road accidents. The demand for such systems in vehicles has been driven mainly by the dynamic development of automotive industry and continually increasing number of vehicles on the road. This paper deals with safety systems that monitor wheel longitudinal slip, with emphasis on testing an anti-lock braking system (ABS) in a MATLAB/Simulink environment. The aim of the work is to describe the development and operation of ABS, electronic stability program (ESP), acceleration slip regulation (ASR) and electronic brakeforce distribution (EBD) systems, and to develop a simulation model of ABS. The relationship between the tire-to-road adhesion coefficient and longitudinal wheel slip was modeled using the Magic Formula equation. The contribution of this system to the vehicle’s braking process on various surfaces (dry asphalt, wet asphalt, snow, and ice) and at various initial velocities was analyzed. In particular, braking distance as a function of time comparing scenarios with ABS activated and deactivated is presented. The structure of the paper includes a theoretical part overviewing automotive safety systems, a description of the ABS model, and an analysis of the results.
subject: SIMRTRANS: Innovative solutions in means of transport
  topic: section
subject: automotive safety systems
  topic: keywords
subject: ABS
  topic: keywords
subject: ESP
  topic: keywords
subject: ASR
  topic: keywords
subject: EBD
  topic: keywords
subject: active safety systems
  topic: keywords
subject: Magic Formula
  topic: keywords
creator: Łukasz KACPRZYCKI
creator: Mateusz BRUKALSKI
creator: Michał Mariusz ABRAMOWSKI
creator: Hubert SAR
creator: Piotr FUNDOWICZ
rights: Copyright (c) 2022 Łukasz KACPRZYCKI, Mateusz BRUKALSKI, Michał Mariusz ABRAMOWSKI, Hubert SAR, Piotr FUNDOWICZ https://creativecommons.org/licenses/by/4.0
date: 2025-09-24
publication date: 2025-09-24
starting page: 339
ending page: 365
doi: 10.24423/engtrans.3463.2025

The Effect of Vocal Effort on Voice Quality in Occupations with High Vocal Load
type: item
description: Phonation type identification and voice quality analysis are often performed using invasive methods such as laryngoscopy or fiberoscopy. This work aims to determine whether comparable results can be reproduced using acoustic analysis, a noninvasive method. The research consists of two series of experiments conducted on two separate groups of professional voice users to calculate the values of voice quality parameters (i.e., peak slope, normalized amplitude quotient, cepstral peak prominence, harmonics-to-noise ratio). The first experiment focused on recording voice in the sound studio (22 participants), while the second focused on collecting data using a dedicated mobile app outside the sound studio (20 participants). The collected samples were then analyzed to examine the effects of vocal load on voice quality and to determine variations between different groups of test participants. According to the results of the experiments, vocal load and working professionally with voice change the value of normalized amplitude quotient (NAQ). Furthermore, it has been shown that harmonics-to-noise ratio (HNR) and cepstral peak performance (CPP) vary with regular hydration status.
subject: OSA2024
  topic: section
subject: voice quality
  topic: keywords
subject: acoustic analysis
  topic: keywords
subject: vocal load
  topic: keywords
subject: vocal exhaustion
  topic: keywords
subject: phonation type
  topic: keywords
subject: hydration
  topic: keywords
creator: Mateusz STERCZEWSKI
creator: Daniel TRZASKOMA
creator: Krzysztof SZKLANNY
rights: Copyright (c) 2022 Mateusz STERCZEWSKI, Daniel TRZASKOMA, Krzysztof SZKLANNY https://creativecommons.org/licenses/by/4.0
date: 2025-07-15
publication date: 2025-07-15
doi: 10.24423/engtrans.3374.2025

A Comprehensive Review on the Applications of Nanometal Additives in Fuels for Internal Combustion Engines
type: item
description: Nanometal additives have emerged as promising candidates for enhancing the performance and efficiency of internal combustion (IC) engines. The present review provides an overview of their applications and benefits in IC engines. These additives, characterized by their nanoscale size and unique properties, offer advantages such as improved combustion kinetics, enhanced catalytic activity, and reduced emissions. By leveraging their high surface-to-volume ratios and tailored surface chemistry, nanometal additives facilitate more efficient fuel combustion, leading to higher engine efficiency and lower pollutant emissions. Also, this review highlights the importance of nanometal additives in addressing challenges related to fuel quality, combustion efficiency, and environmental impact in IC engines, paving the way for cleaner and more efficient engine technologies.
subject: Review Papers
  topic: section
subject: internal combustion engines
  topic: keywords
subject: fuels
  topic: keywords
subject: fuel additives
  topic: keywords
subject: nanometal additives
  topic: keywords
creator: Udayakumar MOHAN
creator: Selvaraju SIVAMANI
rights: Copyright (c) 2025 Udayakumar MOHAN, Selvaraju SIVAMANI https://creativecommons.org/licenses/by/4.0
date: 2025-06-26
publication date: 2025-06-26
starting page: 127
ending page: 156
doi: 10.24423/engtrans.3435.2025

Comparative Study of Matrix Methods for Modeling the Dispersive Character of Ultrasonic Guided Waves
type: item
description: This paper presents a comparative study of various matrix methods for obtaining the dispersion curves of ultrasonic guided waves in anisotropic media for both planar and cylindrical geometries. First, the mathematical formulation of the problem is introduced. Then, matrix methods are employed to generate the characteristic dispersion functions, with a particular focus on multilayer structures. To simplify the problem and enhance convergence, the formulation of Lamb modes is separated from that of shear modes. Dispersion curves are then plotted for single and multilayer planar and cylindrical geometries of propagating modes, with each case identifying the different modes obtained and explaining their symmetry characteristics. The dispersion curves are generated using a MATLAB program and compared with two software tools: Disperse Calculator for plates and GUIGUW for cylindrical structures. A perfect match is observed. A discussion is then presented to highlight the advantages and limitations of the matrix methods, offering reliable insights into which matrix method is most suitable for each type of waveguide and enabling the plotting of convergent curves with minimal computation time.
subject: Technical Notes
  topic: section
subject: guided waves
  topic: keywords
subject: dispersion curves
  topic: keywords
subject: composite
  topic: keywords
subject: laminate
  topic: keywords
subject: matrix method
  topic: keywords
subject: pipeline
  topic: keywords
creator: Ismaine ZITOUNI
creator: Hassan RHIMINI
creator: Abdelkerim CHOUAF
rights: Copyright (c) 2025 Ismaine ZITOUNI, Hassan RHIMINI, Abdelkerim CHOUAF https://creativecommons.org/licenses/by/4.0
date: 2025-06-26
publication date: 2025-06-26
starting page: 305
ending page: 321
doi: 10.24423/engtrans.3493.2025

Strength Estimation of Teeth Reinforced with Different Types of Post Systems
type: item
description: Posts are permanent, single-tooth and periodontal restorations. During chewing, forces make teeth with posts to undergo complex stresses. The aim of this work is to compare and estimate the upper medial incisors restored with custom posts and prefabricated composite posts reinforced with fibreglass using the finite element method. Modelling and numerical analyses provide the opportunity to evaluate the reconstruction of teeth using custom and prefabricated posts.
subject: SI-SolMech2016
  topic: section
subject: finite element method
  topic: keywords
subject: periodontium
  topic: keywords
subject: prefabricated and custom post
  topic: keywords
creator: Wojciech RYNIEWICZ
creator: Anna Maria RYNIEWICZ
creator: Tomasz MADEJ
creator: Grażyna WIŚNIEWSKA
rights: Copyright (c)
date: 2017-03-20
publication date: 2017-03-20
starting page: 147
ending page: 154
doi: 10.24423/engtrans.741.2017

Investigation of a Vibratory Stress Relief System for Hard-Turned EN 31 Components
type: item
description: This study examines the use of artificial neural networks (ANNs) to forecast and optimize residual stress and Brinell hardness in EN 31 components subjected to vibratory stress relief (VSR). The influence of important process parameters – amplitude, frequency, and time – was determined through comprehensive ANOVA analyses. According to the findings, residual stress and Brinell hardness are substantially influenced by amplitude, while frequency plays a crucial role in managing stress and hardness before VSR. The significance of time varied across different processes. The ANN model consistently demonstrated high predictive accuracy, achieving 99.82% for Brinell hardness after VSR, 98.27% for residual stress after VSR, 99.98% for Brinell hardness before VSR, and 98.20% for residual stress before VSR. Model performance was further improved through data transformation and normalization. A robust framework for optimizing VSR process parameters was established by integrating ANOVA and ANN, which enabled precise control over mechanical properties. This research emphasizes the potential of ANN in predictive modeling and process optimization in materials engineering, providing valuable insights for enhancing the performance and reliability of mechanical components through customized VSR processes.
subject: Research Papers
  topic: section
subject: vibratory stress relief (VSR)
  topic: keywords
subject: residual stress
  topic: keywords
subject: Brinell hardness
  topic: keywords
subject: artificial neural network
  topic: keywords
creator: Pankaj BHOKARE
creator: Vishal VASISTHA
rights: Copyright (c) 2025 Pankaj BHOKARE, Vishal VASISTHA https://creativecommons.org/licenses/by/4.0
date: 2025-06-26
publication date: 2025-06-26
starting page: 177
ending page: 197
doi: 10.24423/engtrans.3440.2025

Modeling of the Acoustic Properties of Foamed Polypropylene Panels
type: item
description: This article presents research on modelling baffles with the desired properties of the sound absorption coefficient (SAC). The purpose of the study was to model and compare the SAC values based on selected theoretical models with the results obtained from measurements of this coefficient in panels made of foamed polypropylene. The assessment of sound absorption properties was carried out using two theoretical models: the Johnson–Champoux–Allard (JCA) model and the Sgard model. The accuracy of the calculated SAC was verified based on laboratory measurements of this parameter for selected material configurations, using the technique of two microphones in an impedance tube. Both theoretical and experimental studies were conducted on porous materials in the form of granules. The application of the Sgard model yielded the best results, with the smallest discrepancies in relation to the experimental tests. The results can be used to improve the SAC and efficiency of acoustic panels whose basic material is foamed polypropylene.
subject: OSA2024
  topic: section
subject: perforated porous material
  topic: keywords
subject: sound absorption coefficient
  topic: keywords
subject: double porosity
  topic: keywords
creator: Patrycja ŚWIRK
creator: Lucyna LENIOWSKA
rights: Copyright (c)
date: 2025-01-28
publication date: 2025-01-28
starting page: 89
ending page: 101
doi: 10.24423/engtrans.3428.2025

Investigating the Mechanical, Physical and Biological Properties of PMMA/TiO2 Composites with Nanoclay for Denture Applications
type: item
description: Prosthodontics uses permanent or removable dentures to replace missing teeth, with partial dentures made from cobalt chromium and full dentures from acrylic resin. This study presents Veracril self-curing acrylic, a material for hybrid artificial denture composites reinforced with montmorillonite (MMT) and titanium oxide (TiO2) particles. It is softer, lighter, and more stable than previous materials. Several experiments (mechanical, physical, and biological) have been carried out to examine the novel composite at various MMT and TiO2 weight ratios. The findings indicate that these additives significantly improve the mechanical properties of the matrix material, making it suitable for denture manufacturing. The addition of MMT as a filler enhances bonding between the matrix and additives. The additives' success in biological tests, including antibacterial activity and toxicity assessments, further supports their suitability for dental applications.
subject: Research Papers
  topic: section
subject: biological properties
  topic: keywords
subject: denture applications
  topic: keywords
subject: nanoclay
  topic: keywords
subject: TiO2
  topic: keywords
subject: nano-composites
  topic: keywords
creator: Shaymaa J. AHMED
creator: Nazar J. ABDULRIDHA
creator: Anwer J. AL-OBAIDI
creator: Hussein DALFI
creator: Amer ALOMARAH
rights: Copyright (c)
date: 2025-03-06
publication date: 2025-03-06
starting page: 29
ending page: 43
doi: 10.24423/engtrans.3449.2025

Enhancement of the Thermal Stability of Engine Block Alloy Al-10Si-1Cu-0.5Mg-0.5Ni-0.5Fe with Trace Additions of Ti and Zr
type: item
description: An investigation was carried out on the Al-10Si-1Cu-0.5Mg-0.5Ni-0.5Fe alloy engine block, emphasizing its physical and mechanical characteristics, as well as the presence of trace titanium (Ti) and zirconium (Zr). Three different alloys underwent processes such as homogenization, T6 solution treatment, quenching, and aging to observe both natural and artificial aging responses. The development of Al2Cu and Mg2Si phases within the aluminum matrix during the aging process led to the attainment of peak-aged strength. However, this strength diminished in the over-aged condition due to precipitation coarsening and recrystallization phenomena. The addition of Ti effectively refined the α-Al grain structure and led to the formation of thermally stable nano-sized Al3Ti dispersoids, which did not significantly enhance strength but prevented a drastic decline in the strength of the thermally damaged alloy. The simultaneous addition of Ti and Zr to the alloy further facilitated the precipitation of Al3(Ti, Zr) dispersoids, enhancing this capability. Trace addition reduced the alloys' toughness as well as thermal conductivity to a small extent due to grain refinement and precipitation formation, but these properties improved during aging due to recovery and recrystallization. Microstructural analysis of the alloys indicated that trace additions facilitated the formation of more finely distributed grains, contributing to grain refinement and preventing recrystallization in the over-aged state. The enhanced homogeneity of the grains due to trace additions was further supported by fractography studies.
subject: Research Papers
  topic: section
subject: Al-Si engine block
  topic: keywords
subject: trace addition
  topic: keywords
subject: age hardening
  topic: keywords
subject: thermal conductivity
  topic: keywords
subject: mechanical properties
  topic: keywords
subject: microstructure
  topic: keywords
creator: Mohammad Salim KAISER
rights: Copyright (c)
date: 2025-02-18
publication date: 2025-02-18
starting page: 3
ending page: 28
doi: 10.24423/engtrans.3430.2025