بحوث سكوبس — فراس ثائر رؤوف المالكي

This study investigates the mechanical and tribological behavior of polyvinylidene fluoride (PVDF)/unsaturated polyester resin (UPR) composites reinforced with 1–5% multi-walled carbon nanotubes (MWCNTs). Research on PVDF-based nanocomposites has increased significantly, according to a quick bibliometric screening of Scopus-indexed publications. MWCNTs were found to be one of the most influential reinforcement keywords, indicating a high level of interest in mechanically optimized polymer systems worldwide. In this study, specimens were tested for tensile, flexural, hardness, impact, wear, and reversed-bending fatigue performance. Results reveal that 3% MWCNT provides optimal strengthening, improving tensile and flexural properties, hardness, wear resistance, and fatigue life while reducing void content. Finite element simulations using ANSYS aligned with experimental findings, showing deviations below 10%. Statistical analysis (ANOVA) confirmed significant effects of MWCNT content. Overall, PVDF/UPR–MWCNT composites demonstrate excellent potential for advanced lightweight structural applications. © 2026 Bumi Publikasi Nusantara.

In this work, rectangular plate samples are designed and fabricated using four arrangements: pure epoxy with a stiffener, pure epoxy plate without a stiffener, homogeneous composite plate with 0.5% Vf and a stiffener, and homogeneous composite plate with a FGM stiffener. The mathematical model is formulated based on the first-order shear deformation theory (FSDT). The free vibration test is conducted, and the signal is analyzed to obtain the free vibration characteristics. The results show that the homogeneous composite plate with 2% Vf and FGM stiffener exhibited a significant improvement in the natural frequency. However, using a Functionally Graded Material (FGM) stiffener and increasing the nano-volume fraction increases the natural frequency. Also, the plate without any filler (pure epoxy) and without a stiffener has the lowest frequencies among the composite plates employed. The discrepancy between the analytical and experimental techniques was no more than 10%. © 2026 University of Tehran. All rights reserved.

This study numerically investigates the effect of different microchannel geometries integrated into the absorber tube on the thermal performance of a parabolic trough solar collector. Four configurations were analyzed: empty (straight pipe), circular, square, and triangular microchannels. Computational Fluid Dynamics simulations were conducted using ANSYS Fluent 19.0, adopting a Finite Volume Method with a pressure-based solver, the SIMPLE algorithm for pressure–velocity coupling, and second-order upwind discretization for momentum and energy equations. Simulations were performed across mass flow rates ranging from 0.25 to 1.0 kg/h, with an inlet fluid temperature of 25°C and a constant solar irradiance of 884 W/m2. The corresponding Reynolds numbers ranged approximately from 110 to 420, indicating laminar flow across all cases. Among the configurations, the triangular microchannel exhibited the best performance. At 0.25 kg/h, it achieved an outlet temperature of 101.73°C and a thermal efficiency of 85%, compared with 92°C and 37.15% in the nonchanneled base case. At 1.0 kg/h, the triangular design reached a Nusselt number of 30.48, more than double that of the baseline (14.45), indicating superior convective heat transfer. Validation against published results showed a maximum deviation of only 2.6%, confirming the accuracy of the simulation model. The findings highlight that triangular and square microchannels significantly enhance heat transfer and thermal efficiency, particularly at low flow rates, making them promising designs for advancing solar thermal energy systems. © 2025 Wiley Periodicals LLC.

Purpose: This paper aims to perform theoretical and experimental analysis to modify the mechanical properties of the composite materials reinforced with powders and short fibers using different volume fractions and resins. Design/methodology/approach: The experimental work involved manufacturing composite laminates and testing the prepared samples under tension to obtain their mechanical properties. The theoretical work involves the calculation of the modulus of elasticity for comparison purposes. This work estimated the modulus of elasticity for short fibers (glass, carbon high-strength, boron) as reinforcements and its properties are evaluated. They were used as powders and discontinuous fibers with different resins, epoxy, polyester, nylon and polyester (PL) matrices. As a result of their balance between performance, cost and processing advantages, short fibers are an effective reinforcement for composite materials, particularly in applications where performance is required but cost or processing constraints are present. Among their key advantages are improved mechanical properties, easy manufacturing techniques, strength, damping capacity, toughness and design flexibility. Findings: The results demonstrated a strong agreement between the experimental and theoretical findings, with a maximum difference of no more than 11.6%. The mechanical properties showed that the powder types have an insignificant effect on the mechanical properties of composite materials while the reinforcement types have shown a significant effect. Practical implications: The benefits that fiber matrix composites offer in terms of performance, affordability and structural efficiency are driving their expanding use in aerospace, marine and many other industries. Originality/value: The results demonstrated that short fiber reinforcement significantly enhanced the composite’s modulus of elasticity and strength by over 50%. The type of short fibers used had a greater impact on these improvements compared to other types of reinforcement fibers. © 2025, Emerald Publishing Limited.

This study investigates the effect of helix angle on the performance of electric vehicle transmission systems using a helical-rotor-geared test apparatus. Several gears and pinions with different helix angles were manufactured and tested at two rotational speeds. The research combined theoretical modeling and finite element analysis to calculate natural frequencies, followed by vibration analysis using an experimental setup. The Fast Fourier Transform was applied to accelerometer data to evaluate the dynamic behavior. The results showed that larger helix angles reduced vibration amplitude and noise levels. This occurs because smoother meshing at higher angles leads to improved load distribution and lower transmission disturbances. The combination of simulation and physical testing supports the optimization of gear dynamics in electric vehicle powertrains, contributing to quieter and more efficient systems. © 2025 Universitas Pendidikan Indonesia.

– Recent years have witnessed a widespread demand for the manufacture of hand prosthetics using the 3D printing method, or what is known as additive manufacturing. This study aims to design and analyze a prototype of a prosthetic hand designed by using the SolidWork program and manufactured by 3D printing techniques, with an Ansys using Finite Element Analysis (FEA) in order to determine the maximum amount of stress that the prototype can withstand at different loading conditions and the amount of total deformation. The printing has been performed in a Fused Deposition Modeling (FDM) with Polylactic Acid (PLA) material. The results have showed that the proposed model has given acceptable values concerning von Mises stress and deformation for different loading conditions. Copyright © 2024 Praise Worthy Prize S.r.l.-All rights reserved. © 2024 Praise Worthy Prize S.r.l.-All rights reserved.