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Abstract In the present work, a simple intelligence-based computation of artificial neural networks with the Levenberg-Marquardt backpropagation algorithm is developed to analyze the new ferromagnetic hybrid nanofluid flow model in the presence of a magnetic dipole within the context of flow over a stretching sheet. A combination of cobalt and iron (III) oxide (Co-Fe2O3) is strategically selected as ferromagnetic hybrid nanoparticles within the base fluid, water. The initial representation of the developed ferromagnetic hybrid nanofluid flow model, which is a system of highly nonlinear partial differential equations, is transformed into a system of nonlinear ordinary differential equations using appropriate similarity transformations. The reference data set of the possible outcomes is obtained from bvp4c for varying the parameters of the ferromagnetic hybrid nanofluid flow model. The estimated solutions of the proposed model are described during the testing, training, and validation phases of the backpropagated neural network. The performance evaluation and comparative study of the algorithm are carried out by regression analysis, error histograms, function fitting graphs, and mean squared error results. The findings of our study analyze the increasing effect of the ferrohydrodynamic interaction parameter $$\beta$$ β to enhance the temperature and velocity profiles, while increasing the thermal relaxation parameter $$\alpha$$ α decreases the temperature profile. The performance on MSE was shown for the temperature and velocity profiles of the developed model about 9.1703e−10, 7.1313ee−10, 3.1462e−10, and 4.8747e−10. The accuracy of the artificial neural networks with the Levenberg-Marquardt algorithm method is confirmed through various analyses and comparative results with the reference data. The purpose of this study is to enhance understanding of ferromagnetic hybrid nanofluid flow models using artificial neural networks with the Levenberg-Marquardt algorithm, offering precise analysis of key parameter effects on temperature and velocity profiles. Future studies will provide novel soft computing methods that leverage artificial neural networks to effectively solve problems in fluid mechanics and expand to engineering applications, improving their usefulness in tackling real-world problems.

In this study, a support vector machine (SVM) and three optimization algorithms are used to develop a discharge coefficient (Cd) prediction model for the semi-circular side weir (SCSW). After that, we derived the input and output parameters of the model by dimensionless analysis as the ratio of the flow depth at the weir crest point upstream to the diameter (h1/D), the ratio of main channel width to diameter (B/D), the ratio of side weir height to diameter (P/D), upstream of side weir Froude number (Fr), and Cd. The sensitivity coefficients for dimensionless parameters to Cd were calculated based on Sobol's method. The research shows that SVM and Genetic Algorithm (GA-SVM) have high prediction accuracy and generalization ability; the average error and maximum error were 0.08 and 2.47%, respectively, which were about 95.72 and 60.86% lower compared with the traditional empirical model. The first-order sensitivity coefficients S1 and global sensitivity coefficients Si of h1/D, B/D, P/D, and Fr were 0.35, 0.07, 0.13, and 0.02; 0.63, 0.25, 0.30, and 0.32, respectively. h1/D has a significant effect on Cd. In particular, when h1/D < 0.24 and 0.48 < Fr < 0.58, 0.67 < Fr < 0.72, the discharge capacity of the SCSW is relatively large. HIGHLIGHTS We developed an effective and high-accuracy model for predicting the Cd of SCSW.; The importance of dimensionless parameters on Cd was quantified by Sobol's method.; It explored the flow characteristics of semi-circular side weir.;

Deep-sea hydraulic collection is a key technology for seabed mineral resource extraction, offering higher efficiency and environmental protection compared to other collection methods. However, due to their complex characteristics, the suction properties and influencing factors of polyhedral particles in hydraulic suction collection remain elusive. This study utilized dimensionless methods and conducted experiments to analyze the flow characteristics in cone-shaped collection hoods and the distribution of suction force on polyhedral particles, and researched the effect of various parameters, such as Φ, H/R, R/S, and H/dp (referring to the nomenclature given in the last part of this paper), on the suction force coefficients of polyhedral particles based on the suction force coefficients of spheres by acquiring the suction coefficient ratio (kc). The results indicate the following: (1) the presence of suction and coherent vortices in the horizontal positions of 0.1R to 0.2R within the central region, which move with changes in pump suction or cove height, benefiting particle collection; (2) the particle suction force (Fd) decreases with increasing sphericity (Φ), with a more pronounced decline in high-speed flow fields, exhibiting two peaks and one trough in the Fd curve within the hood’s flow field; (3) the kc generally increases with decreasing Φ at the same collection position, showing increasingly stable fluctuations, and kc is sensitive to surrounding flow velocities with a rapid growth trend at higher speed, revealing that the suction coefficient (Cd) of polyhedral particles is significantly larger than that of spherical particles with increasing flow speed in high-speed flow fields; (4) Fd decreases with increasing H/dp, with a noticeable slowdown when H/dp exceeds 3.5. This study reveals the force characteristics and influencing factors of non-spherical coarse particles in hydraulic suction collection flow fields, providing insights for the development of collection technologies and equipment for deep-sea solid mineral resources, particularly irregular coarse particles.

Combined structure of weir and gate due to the simultaneous flow of suspended material from on the overflow and material deposited in the flow of water from the valve section, provides better conditions compared to other structures used to measure the discharge in the channels. Nowadays, numerical solution methods without the need of laboratory equipment and the ability to calculate the desired parameters, with low time and cost is considered as one of the efficient methods of flow analysis. In this research, by using CFD and numerical solution method with FLOW-3D software for different diameters of combined structure of weir and gate was simulated. Flow simulation was performed in a channel with 3 mm length, 0.4 mm width and 0.5 mm height. The models were studied in cylindrical diameter of 5, 7.5, 10 and 12.5 cm, and for openings gates of 1, 2 and 3 cm. The flow was also simulated and studied for all models at 4 discharges of 12, 16, 20 and 22 lit/s. Comparing the discharge coefficient results with the dimensionless parameter of water depth upstream to water depth downstream of the overflow-valve combined model, it was observed that the numerical results obtained using the RNG turbulence model provide closer data to laboratory results. In the validation stage of numerical results with laboratory outputs of previous researches, the error percentage of the simulated model was calculated to be less than 5%, which indicates the acceptable accuracy of numerical modeling. The results showed that with increasing the flow, when the diameter and opening of the valve are fixed, the flow coefficient increases. At a constant diameter of the overflow-valve model, the flow coefficient decreases in exchange for increasing the valve opening. For a constant flow rate and diameter, changes in flow rate decrease with increasing valve opening height. It was also observed that the curvature of the flow surface profile increases with increasing diameter of the cylindrical model.

The free convection flow of Prabhakar fractional Jeffrey fluid on an oscillated vertical plate with homogenous heat flux is investigated. With the help of the Laplace transform and the Boussinesq's approximation, precise solutions for dimensionless momentum may be found. The temperature and velocity of Prabhakar fractional time free convection flows are compared to conventional thermal transport, as shown by Fourier's law. They met all of the requirements and recovered Newtonian and ordinary Jeffrey fluid solutions from fractional Jeffrey fluid. Finally, graphs show the effect of various physical parameters such as fractional parameters, Grashof number, Prandtl number and Jeffrey parameters on both temperature and velocity.

Unconventional reservoirs are normally characterized by dual porous media, which has both multi-scale pore and fracture structures, such as low permeability or tight oil reservoirs. The seepage characteristics of such reservoirs is mainly determined by micro-fractures, but conventional laboratory experimental methods are difficult to measure it, which is attribute to the dynamic cracking of these micro-fractures. The emerging digital core technology in recent years can solve this problem by developing an accurate pore network model and a rational simulation approach. In this study, a novel pore-fracture dual network model was established based on percolation theory. Fluid flow in the pore of two scales, micro-fracture and matrix pore, were considered, also with the impact of micro-fracture opening and closing during flow. Some seepage characteristic parameters, such as fluid saturations, capillary pressure, relative permeabilities, displacement efficiency in different flow stage, can be predicted by proposed calculating method. Through these work, seepage characteristics of dual porous media can be achieved.

This work presents a physics-based predictive model for temperature rise in cylindrical solids heated by constant-strength, periodic-motion heat source. The heat source motion path, heat transfer boundary conditions and solid dimension are considered in the theoretical model. Analytical solutions to both the infinite or finite length cylinders are constructed with respect to convection and corresponding boundary conditions. Dimensionless controlling parameters are discussed to reveal temperature field evolution. The predicted results in the temperature rise agreed well with the measured data for a Z-direction feeding drive screw shaft system. The proposed model provides an efficient and accurate design tool for engineering calculation and process-parameter planning through inverse analysis.

In this study, the tensile strength, impact strength, and the hardness of the weld are determined. A criterion is proposed for describing the effect of residual stress on the weld mechanical properties. Dimensionless parameters such as Rya (the average of residual stress over the material yield strength), Rym (the maximum residual stress over the material yield strength), Ru2 (the difference in the residual stress over the material ultimate strength), and Ru3 (the difference ratio between the maximum and minimum of three-dimensional residual stresses over the material ultimate strength) are presented to describe the influence of residual stresses on the actual mechanical behavior of the welded pipe. Maximum Rya criterion and lowest strength are obtained at the weld gap center on the external surface of the pipe. The sharp decline in Ru2 criteria is consistent with the severe reduction in impact strength perpendicular to the weld gap.

To reveal the temperature rise evolution mechanism of isotropic media subjected to reciprocating motion constant-strength point heat source, various forms of analytical solutions are derived on the basis of differentiated relative scales, and non-dimensionalized parameters are designed to characterize the thermal distribution regularities by utilizing numerical calculations. Temperature rise curves of media subjected to a reciprocating motion point heat source allow similar quasi-steady-state characteristics to appear, which finally achieve a stable state, so that the values of surplus temperature oscillate around the constant time-average quantity. The time to reach quasi-steady state, the time-averaged quantity and the fluctuation amplitude of surplus temperature are comprehensively impacted by the dimensionless distance parameter γ, the convective heat transfer parameter ω and the velocity and travel parameter β. This work discusses influence rules of temperature evolution in various relative-scale media and further enriches the moving heat source theory.

The purpose of this study is to obtain better physical understandings of the theoretical thresholds of the insonation acoustic pressure amplitudes for medical diagnostic ultrasound applications. For this purpose, a physical model in terms of non-linear resonance of single bubble volumetric oscillations has been developed, to reproduce the threshold insonation acoustic pressure amplitudes that are numerical solutions of Gilmore's equation. It is confirmed, under the condition of the adiabatic state change of the in-bubble gas with a maximum temperature of 5000 K, the present model well-reproduces the influences of the insonation center frequency, the liquid viscosity and surface tension in a range of 0.5 to 16 MHz, 0.0 to 8.0 mPa･s, and 30 to 70 mN/s, respectively, on the threshold insonation acoustic pressure amplitudes. Based on this model, a dimensionless physical index of the insonation acoustic pressure amplitude with a threshold value and a set of fundamental dimensionless parameters constituting that index are defined.

Film downflow from captured liquid without wave formation and its destruction is one of the most important aspects in the development of separation equipment. Consequently, it is necessary to create well-organized liquid draining in areas of captured liquid. Thus, the proposed 3D mathematical model of film downflow allows for the determination of the hydrodynamic parameters of the liquid film flow and the interfacial surface. As a result, it was discovered that the interfacial surface depends on the proposed dimensionless criterion, which includes internal friction stress, channel length, and fluid density. Additionally, equations for determining the averaged film thickness, the averaged velocity vectors over the film thickness, the longitudinal and vertical velocity components, and the initial angle of streamline deviation from the vertical axis were analytically obtained.

Wave overtopping at breakwaters is one of their essential hydraulic characteristics when determining the design crest level. This study concentrates on developing a new practical formula on predicting wave overtopping, by implementing two different statistical models, Multiple Linear Regression model (MLR) and Generalized Linear Regression model (GLM). The models consider dependency of overtopping on a wide variety of quantities and yield to simple forms of prediction. Such statistical analysis are performed on a set of data called CLASH (Crest Level Assessment of Coastal Structures by full scale monitoring, neural network prediction and Hazard Analysis on permissible wave overtopping) the most complete and available database on overtopping phenomena. Proposed equations are compared with most recently extracted as well as successful ones. Comprehensive assessments clearly show more accurate predictions in the case of mean overtopping at vertical seawalls.

The shock effects in laser shock processing of NiTi shape memory alloy were studied by dimensional analysis and finite element simulation. The essential dimensionless parameters controlling the residual stress distribution and plastically affected depth were found to be dimensionless pressure duration and peak pressure. By adopting the constitutive model considering the martensitic transformation and plasticity of deformation induced martensite, the influence of dimensionless parameters on the shock effects of shape memory alloy was studied numerically. The numerical results reveal the scaling law of shock effects on those dimensionless parameters quantitatively and the relationship between the plastically affected depth and peak pressure was validated with experimental results. A window of the optimal processing parameters could be obtained based on this study.