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This study aims to address the environmental impact of nondegradable synthetic materials by promoting their reuse. Specifically, it investigates the feasibility of using polyester needle felt carpet waste as the matrix for thermoplastic composites reinforced with glass and jute fibers at various fiber contents (20, 30 and 40 Wt. %).

The research used both glued and unglued carpet wastes to examine the effect of adhesive impurities on composite properties. The mechanical properties of the composites were evaluated through tensile, bending and Izod impact tests. Additionally, scanning electron microscopy was used to observe the microstructural effects of adhesive impurities on the fiber/matrix interface.

The results showed that unglued carpet composites outperformed glued carpet composites, exhibiting 51% greater tensile strength, 294% higher bending strength and 293% superior impact strength on average. The mechanical properties of the unglued carpet composites generally improved with increasing fiber content. In contrast, glued carpet composites demonstrated optimal performance at specific fiber contents within the studied range. Microscopic analysis revealed that adhesive impurities in the glued composites caused fiber/matrix bond disruption and delamination under load.

This study highlights the potential of recycling polyester needle felt carpet waste into high-performance thermoplastic composites. It underscores the significant impact of adhesive impurities on the mechanical properties of these composites and provides insight into optimizing fiber content for improved material performance.

This study aims to analyze the impact of fractional derivatives on heat transfer and entropy generation during transient free convection inside various complex porous enclosures, such as triangle, L-shape and square-containing wavy surfaces. These porous enclosures are saturated with Cu-water nanofluid and subjected to the influence of a uniform magnetic field.

In the present study, Darcy’s model is used for the momentum transport equation in the porous matrix. Additionally, the Caputo time fractional derivative is introduced in the energy equation to assess the heat transfer phenomenon. Furthermore, the total entropy generation has been computed by combining the entropy generation due to fluid friction (S_ff), heat transfer (S_ht) and magnetic field (S_mf). The complete mathematical model is further simulated using the penalty finite element method, and the Caputo time derivative term is approximated using the L1 scheme. The study is conducted for various ranges of the Rayleigh number (102≤Ra≤104), Hartmann number (0≤Ha≤20) and fractional order parameter (0<α<1) with respect to time.

It has been observed that the fractional order parameter α governs the characteristics of entropy generation and heat transfer within the selected range of parameters. The Bejan number associated with heat transfer (Be_ht), fluid friction (Be_ff) and magnetic field (Be_mf) further demonstrate the dominance of flow irreversibilities. It becomes evident that the initial evolution state of streamlines, isotherms and local entropy varies according to the choice of α. Additionally, increasing Ra values from 10² to 10⁴ shows that the heat transfer rate increases by 123.8% for a square wavy enclosure, 7.4% for a triangle enclosure and 69.6% for an L-shape enclosure. Moreover, an increase in the value of Ha leads to a reduction in heat transfer rates and entropy generation. In this case, Bemf→1 shows the dominance of the magnetic field irreversibility in the total entropy generation.

Recently, fractional-order models have been widely used to express numerous physical phenomena, such as anomalous diffusion and dispersion in complex viscoelastic porous media. These models offer a more accurate representation of physical reality that classical models fail to capture; this is why they find a broad range of applications in science and engineering.

The fractional derivative model is used to illustrate the flow pattern, heat transfer and entropy-generating characteristics under the influence of a magnetic field. Furthermore, to the best of the author’s knowledge, a fractional-derivative-based mathematical model for the entropy generation phenomenon in complex porous enclosures has not been previously developed or studied.

The purpose of this paper is to propose an effective numerical approach for solving the natural convection in a two-dimensional square enclosure by using the single relaxation time-Bhatnagar, Gross and Krook (SRT-BGK) model (D2Q9) and lattice Boltzmann method (LBM).

Navier–Stroke equation is replaced by lattice Boltzmann method, and the numerical approach was simulated using LBM. LBM is a linear equation so, it reduces the computational time. The governing equations are solved using the SRT-BGK model. To achieve better numerical stability and accuracy, the momentum and energy equations are solved using two-dimensional nine-directional (D2Q9) lattice arrangement.

The results are presented at different convection mechanism with constant Prandtl number = 0.71, and the result is validated with reported literature. Numerical investigation is performed and accurate results are obtained; the range of Pr = 0.71, various Rayleigh number, phase change, periodicity parameter and amplitude ratio with three different blockage ratios. The present study is performed using LBM.

To extend this work, the influence of natural convection, various selections of Prandtl number and Rayleigh number, periodicity and the effect of aspect ratio with mounted number of blockages could be included.

This research article will be useful for the study of fluid flow and heat transfer in hot and cold fluid interaction over the solid object. Like gear hardening with various sizes of gear blocks, material processing with hot and cold fluid interactions inside the furnace wall, solar panels high and low density fluid variation, indoor hot and cold fluid thermal environments, inside nuclear reactors heat and heavy water fluid interaction, cooling of electronic equipments and various chemical engineering applications.

This paper will be useful for studying fluid flow and heat transfer within a square enclosure, and it gives practical information in engineering and heat transfer applications.

The present work is the first to investigate using LBM for selected parameters to apply a natural convection with imposed sinusoidal wave for different convection mechanisms.

The purpose of the study is to quantitatively evaluate the role of landscape values and factors in urban parks experimentally based on neuroscience.

In the first step, ten major parks were selected out of 59 regional and trans-regional parks in Tehran for field study analysis. Next, considering the diversity and abundance of landscape elements in the selected parks, Mellat Park was chosen for the case study.

The fixation duration of the factors has an average correlation coefficient of 0.5865, −0.5035 and −0.5125 for the overall sketch map, quality and accuracy, respectively. The results indicated that the “quality of people's cognitive maps” has a direct relation to fixation duration on “human-made factors” and an inverse relation to fixation duration on “natural factors” and “human activities and behavioral factors” in the park.

The results can pave the way for further research in the interdisciplinary fields of landscape architecture and neuroscience.

Legibility is a superior quality of urban spaces that profoundly affect how people perceive and behave.

This paper aims to investigate the entropy generation due to magnetohydrodynamic natural convection flow and heat transfer in a porous enclosure filled with Cu-water nanofluid in the presence of viscous dissipation effect. The left and right walls of the cavity are thermally insulated. There are heated and cold parts, and these are placed on the bottom and top wall, respectively, whereas the remaining parts are thermally insulated.

The finite volume method is used to solve the dimensionless partial differential equations governing the problem. A comparison with previously published woks is presented and is found to be in an excellent agreement.

The minimization of entropy generation and local heat transfer according to different values of the governing parameters are presented in details. It is found that the presence of magnetic field has negative effects on the local entropy generation because of heat transfer and the local total entropy generation. Also, the increase in the heated part length leads to a decrease in the local Nusselt number.

This problem is original, as it has not been considered previously.