Résumé: The research conducted focused on examining the unique properties of Agave Americana Flower Stem fiber (AAFS), particularly its behavior under quasi-static tensile conditions. A total of 200 AAFS fibers were subjected to tensile tests using a standard gauge length of 40 mm. Tests spanned seven groups with quantities (N) ranging from 30 to 200. The study aimed to understand the fibers’ mechanical traits, as tensile resistance and modulus of elasticity, and to see how different test quantities influence these properties. A significant observation was the dispersion of the tensile characteristics of AAFS fibers, a common trait of natural fibers. To understand this, we applied rigorous statistical tools, including the Weibull distribution at a 95% confidence interval and one-way ANOVA. A mathematical model was produced utilizing data from experiments regarding the tensile behavior of AAFS fibers. The ANN provided correlation coefficients (R2) of 0.9897, 0.9971, 0.9993, and 0.9939 for training, validation, testing, and all datasets respectively, which were able to accurately predict the experimental data. The proposed model would be of tremendous assistance to engineers and designers in obtaining green composite materials that are based on natural fibers and thereby more durable. These methods illuminated the patterns in our results, enriching our understanding of AAFS fiber mechanics.

Résumé: The aggregation of nanoparticles is a major phenomenon having broad consequences in many fields. In order to fully utilize the capabilities of nanoparticles in a variety of applications and to evaluate the effects that they will have on the environment and biological systems, it is crucial to comprehend and manage aggregation. To develop and improve nanoparticle-based technology, researchers are still learning more about the aggregation processes. Thus, the present study investigates the combined effects of velocity slip and nanoparticle aggregation on Heat transfer (HT) analysis of MHD nanofluid (i.e., ) flow between porous convergent, divergent channel. The modified Krieger–Dougarty and Maxwell–Bruggeman models were utilized for nanoparticle aggregation. The modeling is based on nonlinear PDEs such as continuity, momentum, and heat equations. These equations are transformed into a system of nonlinear ODEs using similarity transformations and then solved numerically and analytically. The analytical solution has been constructed using the ADM method. The present results in particular cases are compared to results obtained by the HAM- package and by the Runge- Kutta Fehlberg 4th–5th order (RKF-45) for validation. The effects of active parameters on the velocity, temperature, concentration, skin friction, and Nusselt numbers are investigated. It is found that nanoparticle aggregation can limit fluid velocity in converging channels by increasing flow resistance through aggregate formation. Individual nanoparticles generate friction and lower velocity, while aggregated nanoparticles boost fluid density and velocity. In addition, it is found that the magnetic field lowers skin friction and increases HT due to Lorentz force, while porosity increases friction and HT. Nanoparticle concentration inversely affects friction, increasing friction without aggregation and decreasing friction with aggregation, with the HT rate rising with increased nanoparticle concentrations.

Résumé: This study explores the impact of ternary hybrid nanofluid and velocity slip on the Non-Newtonian fluid flow between two nonparallel plates. Additional influence of an applied magnetic field is considered with Casson fluid (Blood) as a base fluid. Both analytic and numerical techniques are employed to comprehensively analyze the system’s behavior under these combined effects. The governing partial differential equations (PDEs) governing continuity and momentum are simplified into a system of ordinary differential equations (ODEs) through similarity transformations. To obtain an explicit series solution for the resulting problem, we employ the Duan Rach approach (DRA). Subsequently, we conduct a thorough analysis of the solution’s convergence to ensure its reliability and accuracy. The same problem is also solved by using the Runge-Kutta-Fehlberg 4th–5th order approach featuring shooting technique and an excellent agreement is observed between the two sets of results. A comparison was made between the results obtained from this investigation in particular cases and the results obtained via the HAM-based Mathematica package for validation. Influence of various parameters of practical importance on the velocity and temperature profiles is studied and portrayed graphically. Values of skin friction coefficient are tabulated by assigning different values to various emerging parameters. It is found that the velocity slip parameter has a positive value in a converging channel, it implies that there is a slip between the fluid and the channel wall, and the slip velocity is directed in the same direction as the flow. Hence velocity increases. Also, results obtained reveal that for positive value of β + velocity gets high in converging case and lower velocity can be seen in diverging geometry. Same behavior is seen for β −

Résumé: Current study deals with influence of rotating and thermal radiative fluxing on fluid’s thermal, hydrodynamic, and concentration behavior flowing between two nonparallel walls in existence of uniform magnetized force. The modeling is based on nonlinear partial differential equations (PDEs) such as continuity, momentum, temperature, and concentricity equations. These equations are converted into a system of nonlinear ordinary differential equations (ODEs) utilizing similarity transformations. Analytical solution has been constructed using the Differential Transform Method (DTM). The present results are compared to results obtained by the HAM package and by the numerical procedure (RKF-45) for validation. The impacts of active variables like the rotational factor, Hartmann, Schmidt numbers, and thermal radiation parameter, are investigated on the rapidity, temperature, and concentricity profiles. Moreover, frictional force factor, Nusselt, and Sherwood quantities. It is found that speed and concentricity of the fluid flow increase with the growth of Hartmann number, whereas a reverse behaviour is observed for thermal distribution. Results obtained also reveal an improvement in frictional force factor, Nusselt and Sherwood numbers with the enhancement of Reα parameter. It is found that an increase in the rotational parameter Ro and the radiation factor Rd leads to a decrease in the Nusselt number.

Résumé: Double-pass inclined solar chimneys are innovative structures designed to harness solar energy for natural ventilation in habitats. Unlike traditional chimneys, which rely solely on the buoyancy of warm air for ventilation, double-pass inclined solar chimneys incorporate solar heat to enhance airflow. These chimneys consist of two passageways: an outer transparent cover and an inner absorber plate. The transparent cover allows sunlight to penetrate and heat the absorber plate, which in turn heats the air within the chimney. As the air warms, it rises due to buoyancy, creating a draft that draws cooler air from the habitat below. This process creates a continuous airflow within the chimney, facilitating natural ventilation. The inclined design of these chimneys maximizes solar exposure throughout the day, optimizing heat absorption and airflow. Additionally, the double-pass conFigureuration enhances thermal efficiency by trapping and utilizing solar heat effectively. By harnessing renewable solar energy, double-pass inclined solar chimneys offer a sustainable solution for ventilating habitats, reducing reliance on mechanical ventilation systems and lowering energy consumption.They provide a cost-effective and eco-friendly alternative for maintaining indoor air quality and comfort in various living spaces.

Résumé: In the present work, we explored the magnetohydrodynamic flow in the pressure gradient across a flat plate. The effects of the magnetic field and the addition of ternary hybrid nano-fluid (i.e. a mixture of three nanoparticles for example ( ) in mixture base fluid ( ) are also considered in this study. The flow over a flat plate is an interesting analysis for thermal and momentum boundary layers, for the implications of heat transfer, and is applied in numerous technological and industrial fields. Basic partial differential equations are transformed into nonlinear ordinary differential equations using similarity transformation. Then, this equation was treated numerically by the 4th–5th order of the Runge–Kutta–Fehlberg method with shooting approaches and analytically by a new method called the Daftardar-Jafari Method (DJM). The effect of various physical parameters namely the magnetic field , the volumetric fraction of the nanoparticles, the pressure gradient on the velocity distribution and the coefficient of friction , of the theoretical results obtained confirm that the ternary hybrid nano-fluid has a better dynamic property than the hybrid nano-fluid, as well as the efficiency of the adopted DJM technique. This investigation laid out that ternary hybrid nano-fluid possesses excellent thermal execution, more noteworthy than that of hybrid nano-fluid.

Résumé: In this paper, very efficient, intelligent techniques have been used to solve the fourth-order nonlinear ordinary differential equations arising from squeezing unsteady nanofluid flow. The activation functions used to develop the three models are log-sigmoid, radial basis, and tan-sigmoid. The neural network of each scheme is optimized with the interior point method (IPM) to find the weights of the networks. The confrontation of the obtained results with the numerical solutions shows good accuracy of the three schemes. The obtained solutions by utilizing the neural network technique of our variables field (velocity and temperature) are continuous contrary to the discrete form obtained by the numerical scheme.

Résumé: In this paper, the Duan–Rach Approach (DRA) was used to obtain an approximate analytical solution of squeezing unsteady nanofluid flow. An approximate analytical solution can be obtained for a velocity and a temperature profile. This method modifies the standard Adomian Decomposition Method (ADM) by evaluating the inverse operators at the boundary conditions directly. The obtained results show a good agreement with numerical method (fourth order Runge–Kutta algorithm). The algorithm derived from this approach can be easily implemented.

Résumé: In this paper, we apply a new approach of the Adomian decomposition method developed by Duan–Rach (DRA) to solve the MHD Jeffery–Hamel flow. A purely analytical solution can be obtained by this approach. This method modifies the Adomian decomposition method (ADM) by evaluating the inverse operator at the boundary conditions directly. The results show a good agreement with numerical method (4th-order Runge–Kutta algorithm) and homotopy analysis method (HAM). The algorithm derived from this approach can be easily implemented.