Homogeneous Medium Research Articles

Coherent radiation from a chain of charged particles on a circular orbit around a dielectric ball

We investigate the spectral and angular distribution of the electromagnetic radiation from a chain of relativistic charged particles uniformly rotating along equatorial orbit around a dielectric ball. It is shown that, for weak absorption in the ball material and under relatively mild conditions on the distribution of the particles, the radiation intensity at specific rotation frequencies is essentially stronger than the corresponding radiation for a chain circulating in free space or in a homogeneous transparent medium with the same dielectric constant as that for the ball. We determine the values of parameters of the problem for which the charges in the chain emit coherently and the radiation intensity on a given harmonic increases in proportion to the square of the number of emitting charges. We also show that relative shifts in the particles locations up to 10% do not destroy the coherence properties of the radiation. It is demonstrated that the coherence effects may also dominate in the radiation intensity for chains with non-equidistant distributions of particles. The numerical results obtained for different dielectric balls have revealed the emitted radiation to be in the GHz/THz frequency ranges. The high-power radiation from the chain is confined near the rotation plane within the angular region determined by the Cherenkov angle for the velocity of the chain image on the ball surface. In the special case of an equidistant distribution of charged particles along the orbit the results of the present paper for angle integrated frequency distribution of the radiation are in agreement with those previously obtained by our group. We argue that similar coherence effects will be present in the radiation from a chain of bunches circulating around the ball.

Optimal design of multilayer radar absorbing materials: a simulation-optimization approach

Multilayer radar absorbing materials with light weight, strong absorption, and wide absorption bandwidth are urgently demanded with the increase of electromagnetic pollution. However, the current design methods with only simulation operation or optimization strategy are not comprehensive. Here, a simulation-optimization approach including electromagnetic simulation and numerical calculation is proposed based on the interaction between different software, in which the homogeneous medium substitution method is presented to simplify the complicated structures. Besides, return loss and impedance matching of different layer structures are investigated. From the simulated results, it can be found that the structures with better impedance matching have superior absorbing performance. The optimal method shows the advantages of fast and efficient, which has tremendous potential for various applications, such as military stealth and electromagnetic wave elimination.

Evaluating the effect of aquifer heterogeneity on multiobjective optimization of in-situ groundwater bioremediation

In-situ bioremediation is a cost-effective technique to eliminate petroleum hydrocarbons from groundwater. In previous studies, this has been mostly applied under the approximation of a homogeneous porous medium, even though in reality aquifers are often characterized by significant heterogeneities. Here, different heterogeneous and equivalent homogeneous hydraulic conductivity fields are considered to study the effect of aquifer heterogeneity on optimal in-situ bioremediation. For this, the multiobjective simulation-optimization (S/O) model referred to as BIOEFGM-NSGA II is proposed — which uses the element-free Galerkin method (EFGM) for discretization of the governing equations, and the non-dominated sorting genetic algorithm II (NSGA II) for multiobjective optimization. This model is then applied to different heterogeneous conductivity fields generated through a pseudo-random correlated field generator for different combinations of variance and correlation lengths with constant mean. Results show that the optimal pumping policy for an equivalent homogeneous conductivity field violates the constraint of maximum allowable concentration in all the studied heterogeneous fields. To satisfy this constraint, in-situ bioremediation cost increases by 8.47% to 56.83% to that of a homogeneous field. It shows the significance of aquifer heterogeneity in designing an optimized in-situ bioremediation system and hence, should be incorporated in the S/O model for in-situ groundwater bioremediation.

Technical note: The contribution of internal bremsstrahlung to the 90 Y dose point kernel.

Internal dosimetry has an increasing role in the planning and verification of nuclear medicine therapies with radiopharmaceuticals. Dose Point Kernels (DPKs), quantifying the energy deposition all around a point source, in a homogenous medium, are extensively used for 3D dosimetry and nowadays are mostly evaluated by Monte Carlo (MC) simulation. To our knowledge, DPK for beta emitters is estimated neglecting the continuous photon emission due to the Internal Bremsstrahlung (IB), whose contribution to the absorbed dose can be relevant beyond the maximum range of betas, as evidenced in recent works. Aim of this study was to investigate and quantify, by means of MC simulations, the contribution of IB photons to DPK calculated for 90 Y and provide the updated 90 Y DPK. The overall radiation due to the decay of a 90 Y point source, placed at the centre of concentric water shells of increasing radii from 0.02 cm to 20 cm, was simulated with GAMOS, including the IB source term whose spectral distribution was described by an analytical model. Energy deposition was scored in the shells as a function of the distance from the source, R, and DPK was estimated in terms of the scaled absorbed dose fraction, F(R/X90 ), where X90 is the range within which the beta particles deposit 90% of their energy. A comparison between the two simulated absorbed dose distributions, calculated with or without IB, clearly shows that the latter (incomplete) choice is consistent with the findings of other Authors and systematically underestimates the absorbed dose imparted to the tissue. 90 Y DPK values currently used are underestimated by 20%-34% for R>2X90 . The revised values provided in this work suggest that the inclusion of IB emission in DPK evaluations is advisable for pure beta emitters.

Dissipation factor and phase velocity approximate formulas for P-waves in fluid-saturated porous media

Actual sedimentary rocks are generally homogeneous porous media saturated by fluid, which are described by poroelastic media. Wave velocity and dissipation factor in poroelastic media provide essential information about rock and fluid properties and are widely used in many fields. The exact wave velocity and dissipation factor can be obtained from wavenumbers determined by dispersion equation through complex mathematic operations. Reported approximate formulas are most given under the assumption that the characteristic angular frequency (ωc ) is far larger than the angular frequency (ω) and becomes invalid for high frequency. Thus, this paper derived phase velocity and dissipation factor approximation of the two P-waves in poroelastic media for the whole low-frequency range. Based on the Geertsma–Smit approximation, we modified the infinite-frequency limiting velocity for fast P-wave approximation and removed the ω/ωc <<1 assumption for slow P-wave approximation. Numerical analysis shows that the proposed approximate formulas for P-waves in porous media can reveal the exact variations of phase velocity and dissipation factor in the low-frequency range, which is from zero frequency for isotropic media to the characteristic frequency. Phase velocity approximations of the two P-waves in poroelastic media are very close to exact values, with maximum relative errors being far less than 1%.

Solitary wave behavior of (2+1)-dimensional Chaffee-Infante equation.

The behavior of gas diffusion in a homogeneous medium is described by the (2+1)-dimensional Chaffee-Infante equation. In this work, the solitary wave behavior of the (2+1)-dimensional Chaffee-Infante equation is studied with the help of extended sinh-Gordon equation expansion technique. Bright, dark, periodic, kink, anti-kink and singular traveling wave patterns are observed for suitable choice of parameters. The 3D graphs, 2D plots and contour plots are included to understand the dynamics of the obtained solutions. The obtained results depict that the extended sinh-Gordon equation expansion technique provides an efficient tool for solving other equations that occur in different branches of science and technology.

Analyzing Support Stability of Deep Shaft Based on Plastic Softening and Dilatancy of Hard Rock Mass

To explore the stability analyses and control methods for surrounding rocks in deep hard rock shafts, this paper is based on field engineering geological surveys and laboratory rock mechanics tests and relies on the main shaft being constructed in the Shaling Gold Mine of China as the engineering background. The quality of the rock mass is evaluated by the Q system, rock mass rating (RMR) and geological strength index (GSI). The mechanical parameters of the surrounding rock mass of the shaft are calculated by using the generalized Hoek–Brown failure criterion, and the main support system is determined based on the rock mass classification system. Based on the finite element method, a two-dimensional plane strain model is constructed to analyze and evaluate the deformation and plastic region range of surrounding rocks for different support systems. On this basis, considering the dilatancy and plastic softening characteristics of hard rock masses, an analytical solution of the stress, strain and plastic region radius of hard rock around shafts in homogeneous media is proposed. Finally, the plastic region of the surrounding rock is measured by the P-wave velocity test method. The results show that after considering the dilatancy and plastic softening characteristics of the rock mass, the numerical simulation, theoretical analytical solution and measured results are basically consistent, and the proposed support system can effectively ensure the stability of the shaft.

Numerical Simulation of Carbon Dioxide–Nitrogen Mixture Dissolution in Water-Saturated Porous Media: Considering Cross-Diffusion Effects

The possibility of impure carbon dioxide (CO2) sequestration can reduce the cost of these projects and facilitate their widespread adoption. Despite this, there are a limited number of studies that address impure CO2 sequestration aspects. In this study, we examine the convection–diffusion process of the CO2–nitrogen (N2) mixture dissolution in water-saturated porous media through numerical simulations. Cross-diffusion values, as the missing parameters in previous studies, are considered here to see the impact of N2 impurity on dissolution trapping in more realistic conditions. Homogeneous porous media are used to examine this impact without side effects from the heterogeneity, and then simulations are extended to heterogeneous porous media, which are a good representative of the real fields. Heterogeneity in the permeability field is generated with sequential Gaussian simulation. Using the averaged dissolved CO2 and dissolution fluxes for each case, we could determine the onset of different dissolution regimes and behaviors of dissolution fluxes in CO2–N2 mixture dissolution processes. The results show that there is a notable difference between the pure cases and impure cases. Additionally, a failure to recognize the changes in the diffusion matrix and cross-diffusion effects can result in significant errors in the dissolution process. At lower temperatures, the N2 impurity decreases the amount and flux of CO2 dissolution; however, at higher temperatures, sequestrating the CO2–N2 mixture would be a more reasonable choice due to enhancing the dissolution behavior and lowering the project costs. The results of the heterogeneous cases indicate that heterogeneity, in most cases, reduces the averaged dissolved CO2, and dissolution flux and impedes the onset of convection. We believe that the results of this study set a basis for future studies regarding the CO2–N2 mixture sequestration in saline aquifers.

Fast 3D kernel computation method for positron range correction in PET

Objective. The positron range is a fundamental, detector-independent physical limitation to spatial resolution in positron emission tomography (PET) as it causes a significant blurring of underlying activity distribution in the reconstructed images. A major challenge for positron range correction methods is to provide accurate range kernels that inherently incorporate the generally inhomogeneous stopping power, especially at tissue boundaries. In this work, we propose a novel approach to generate accurate three-dimensional (3D) blurring kernels both in homogenous and heterogeneous media to improve PET spatial resolution. Approach. In the proposed approach, positron energy deposition was approximately tracked along straight paths, depending on the positron stopping power of the underlying material. The positron stopping power was derived from the attenuation coefficient of 511 keV gamma photons according to the available PET attenuation maps. Thus, the history of energy deposition is taken into account within the range of kernels. Special emphasis was placed on facilitating the very fast computation of the positron annihilation probability in each voxel. Results. Positron path distributions of 18F in low-density polyurethane were in high agreement with Geant4 simulation at an annihilation probability larger than 10−2 ∼ 10−3 of the maximum annihilation probability. The Geant4 simulation was further validated with measured 18F depth profiles in these polyurethane phantoms. The tissue boundary of water with cortical bone and lung was correctly modeled. Residual artifacts from the numerical computations were in the range of 1%. The calculated annihilation probability in voxels shows an overall difference of less than 20% compared to the Geant4 simulation. Significance. The proposed method is expected to significantly improve spatial resolution for non-standard isotopes by providing sufficiently accurate range kernels, even in the case of significant tissue inhomogeneities.

Photoreactivity of new rose bengal-SiO2 heterogeneous photocatalysts with and without a magnetite core for drug degradation and disinfection

The main drawback of homogeneous photocatalysis is the difficult separation of the photocatalysts from the reaction media after treatment completion; thus, heterogeneous photocatalysis represents a step forward in this technology. Moreover, heterogeneous catalysts incorporating magnetic properties further facilitate their separation and recovery. In this context, some photocatalyst of Rose Bengal (RB) on heterogeneous supports have been synthesized but how derivatization influences its mechanism of action against organic pollutants degradation and water disinfection still deserves a deeper investigation. In this context, new heterogeneous nanosized photocatalysts incorporating Rose Bengal (RB) have been prepared. The first one was based on the covalent anchoring to SiO2 nanoparticles and the second one incorporates a magnetite core. They have demonstrated to efficiently achieve photodegradation of ACF, DCF, and OFX under visible-light irradiation, with greater efficiency in the case of DCF. Interestingly, the photostability of RB is higher in heterogeneous than in homogeneous media. The presence of magnetite core in the heterogeneous photocatalyst facilitates its recovery from the medium but the photophysical properties of RB remain unchanged. These new photocatalysts also show a great efficiency in the photoinactivation of Enterococcus faecalis Gram-positive bacteria but not for the Gram-negative Escherichia coli and Pseudomonas aeruginosa. Analysis of all constants involving the photosensitized degradations of ACF, DCF, and OFX has evidenced that electron transfer process between RB, in homogeneous solutions and as a heterogeneous photocatalyst, and the three drugs is the initial step of their oxidations. In view of the results achieved, we believe that they could be used as a starting point for the development of new RB heterogeneous photocatalyst with adjustable oxidizing properties.

Extracting reference voltages from measurement voltages for oil-water two-phase flow measurement of electrical impedance tomography

To apply electrical impedance tomography (EIT) for heterogeneous two-phase flow measurement, reference voltages have to be measured, which requires the entire pipeline filled with a homogeneous medium. Such process is often time-consuming, costly and infeasible in some cases. Reference voltages acquired initially could not be used later, because of electrical conductivity change of two-phase flow caused by temperature change or chemical reaction. It will be ideal if reference voltages could be extracted from measurement voltages. In this paper, a novel multiple measurements (MMs) method is proposed by data fitting and empirical formula to establish the mapping model from measurement voltages to reference voltages, and the effectiveness of the method is proved by the oil-water two-phase flow experiment. Compared with the measurement-scale feature (MSF) and best homogeneous (BH) methods, the proposed MMs method achieves 6.38% average relative error (RE) and 4.96% average volume fraction relative error (VFRE) in the test set. The work enables the accurate estimation of the reference voltage and thus the accurate measurement of the volume fraction of oil-water two-phase flows, which will broaden the application of EIT in the field of two-phase flow measurement.

MAGNETOHYDRODYNAMIC FLOW AND HEAT TRANSFER THROUGH A CIRCULAR TUBE FILLED WITH HOMOGENEOUS AND HETEROGENEOUS POROUS MEDIUM

In this paper, we study the laminar steady flow of incompressible viscous magnetohydrodynamic (MHD) fluid inside a circular tube filled with homogeneous/heterogeneous porous medium. A transverse uniform/nonuniform magnetic field is applied, along with a uniform heat flux boundary condition. The Brinkman equation is used to model the flow through the saturated porous medium. Exact solutions of velocity and temperature fields, friction factor, and Nusselt number (&lt;i&gt;Nu&lt;/i&gt;) in terms of the shape parameter (&amp;sigma;) and Hartmann number (&lt;i&gt;M&lt;/i&gt;) are presented. In the limit of the zero shape parameter and the absence of magnetic field, the Brinkman model results converge to the Hagen-Poiseuille flow solution of circular pipe flow. In the opposite limit of the infinite shape parameter and the absence of magnetic field, the solutions approach the Darcy model results. In terms of the hydro-thermal characteristics of the flow, the Poiseuille flow results and the Darcy model results are shown to serve as the lower and upper bounds, respectively. A significant increase in the heat transfer in heterogeneous porous medium with the nonuniform magnetic field (highest &lt;i&gt;Nu&lt;/i&gt; &amp;#61; 12) compared to homogeneous porous medium with uniform magnetic field is identified (highest &lt;i&gt;Nu&lt;/i&gt; &amp;#61; 8). We also validate the results of homogeneous and heterogeneous porous medium with uniform/nonuniform magnetic field using numerical solutions.

SOLUTION OF COUNTER-CURRENT IMBIBITION PHENOMENON IN FLUID FLOW THROUGH INCLINED POROUS MEDIA BY REDUCED DIFFERENTIAL TRANSFORM METHOD

This study presents the mathematical model of the counter-current imbibition phenomenon that occurs through inclined homogeneous and heterogeneous porous media. The effect of relative permeability, capillarity, and heterogeneity of porous materials such as glass beads, touchet silt loam, and fragmented mixture on the saturation rate of a reservoir is investigated and discussed. A variety of different types of sand have been considered for various lengths of time and distances in the current model in order to compare saturation levels between homogeneous and heterogeneous porous media. The reduced differential transform method (RDTM) is used to obtain an approximate analytical solution to the proposed model. The findings, illustrated both numerically and graphically, are presented for the distance and time variables.

Tensor- and spinor-valued random fields with applications to continuum physics and cosmology

In this paper, we review the history, current state-of-art, and physical applications of the spectral theory of two classes of random functions. One class consists of homogeneous and isotropic random fields defined on a Euclidean space and taking values in a real finite-dimensional linear space. In applications to continuum physics, such a field describes the physical properties of a homogeneous and isotropic continuous medium in the situation, when a microstructure is attached to all medium points. The range of the field is the fixed point set of a symmetry class, where two compact Lie groups act by orthogonal representations. The material symmetry group of a homogeneous medium is the same at each point and acts trivially, while the group of physical symmetries may act nontrivially. In an isotropic random medium, the rank 1 (resp., rank 2) correlation tensors of the field transform under the action of the group of physical symmetries according to the above representation (resp., its tensor square), making the field isotropic. Another class consists of isotropic random cross-sections of homogeneous vector bundles over a coset space of a compact Lie group. In applications to cosmology, the coset space models the sky sphere, while the random cross-section models a cosmic background. The Cosmological Principle ensures that the cross-section is isotropic. For the convenience of the reader, a necessary material from multilinear algebra, representation theory, and differential geometry is reviewed in Appendix.

Land subsidence due to natural gas extraction in the Thrace basin (NW Turkey) and its influence on the North Anatolian fault under the Marmara Sea

We map surface deformation in the Thrace region of Turkey using the Sentinel-1 Synthetic Aperture Radar (SAR) data. Interferometric Synthetic Aperture Radar (InSAR) time series analysis of the SAR data acquired between 2014 and 2020 on ascending and descending orbits reveals large-scale subsidence (~110 × 60 km) with rates reaching up to 10 ± 1.5 mm/yr. We relate this deformation to natural gas reservoir operations, such as gas exploitation and extraction activities that have been taking place in the region for decades, an inference being supported by the strong correlation between the InSAR time series and the variation in natural gas production during the same time period in the Thrace region reported by the Energy Market Regulation Authority of Turkey. Assuming that the observed subsidence is caused by compaction of sediments in the natural gas reservoirs, we construct a triangulated surface enveloping roughly at the bottom of the gas extraction wells and use it to invert the amount of negative opening (hence volume loss) on triangular elements that are assumed to be buried in an elastic and homogeneous medium. Coulomb stress changes caused by this volume change on the North Anatolian Fault at the Sea of Marmara are found to be insignificant (less than 10?5 Mega-Pascal) to perturb the state of the stress around the Marmara seismic gap. Yet, the large-scale subsidence revealed in this study needs to be taken into consideration when assessing hazards for the infrastructures, settlements, and other engineering structures, particularly in case of a large earthquake in the Marmara Seismic Gap.

Observation of Aulter–Townes splitting in subwavelength grating metamaterial ring resonators

Subwavelength grating metamaterial (SGM) waveguide is typically treated as a homogeneous medium without considering intra-waveguide reflection. However, this approximation is not always valid, especially in resonators. In this paper, we show that the reflection-induced mutual coupling between the clock-wise and counter-clock-wise resonant modes in a subwavelength grating metamaterial waveguide ring resonator (SGMRR) breaks the degeneracy of the two modes, leading to the formation of Autler–Townes splitting. This phenomenon could be leveraged to improve the detection limit of SGMRR-based sensors.

Исследование изменения электромагнитных параметров в управляемых асинхронных специальных электрических приводах

The article researches the changes in the electromagnetic parameters of controlled asynchronous special electric drives. Special asynchronous electric drives are controlled cascade electric drives of cylindrical and axial designs. The study of the dynamics of parameter changes is carried out on the basis of the method of electromagnetic energy conversion and the theory of electromagnetic circuits. As a result, for new mathematical models of the electromagnetic system of the studied asynchronous electric drives, the parameters of the electromagnetic field of a closed coil of one coil of an electric winding with electric current in a homogeneous medium are determined. The solved problem is spatial, since the distribution of electromagnetic induction in a coil of a given shape of an electromagnetic coil is determined. The obtained conclusions for determining the electromagnetic parameters of cylindrical and axial motors of special electric drives allow us to correctly solve the problems of modeling, designing and improving the efficiency of the studied electric drives and electromechanical energy converters of cylindrical and axial designs. The results of the study are applicable to create a computer-aided design system for the research asynchronous electric drives and solve modeling and design problems. The conducted research allows creating electric drives with optimal weight, size and energy indicators.

Use of the repeated integral transformation method to describe the transport of solute in soil

Predicting the fate and transport of contaminants in soil or groundwater systems using analytical or numerical models is crucial for environmental researchers. While the analytical models are a flexible approach to quantifying the subsurface contamination and remediation because they are non-susceptible to numerical dispersions, economical and handier; two-dimensional analytical models that describe a bilateral flow coupled with both sink and decay factors are rarely reported. Motivated by the case of a non-bare soil ridge with constant point-solute source lying internally but parallel to the longitudinal flow direction, a (2 + 1) dimensional Advection-Diffusion-Reaction Equation (ADRE) of bilateral flow coupled with the linear sorption, decay, and sink is formulated to model the transport of dissolved solute in a homogenous and isotropic non-fractured porous medium. Then, a brief review of exact and analytical methods for solving the ADRE is conducted to establish the right solution methods. The Repeated Integral Transformation Method (RITM) is employed to derive the approximate analytical solutions for the formulated model, maintaining the model's original terms for the efficient sensitivity analysis. The RITM uses Laplace and Fourier transforms with a wide range of computed results. We compare the approximate solutions with numerical simulations in COMSOL to verify the accuracy of the approximate analytical models. Then, the application of the solutions is demonstrated through a systematic analysis of the effect on solute transport of advection-diffusion, reaction, sorption, retardation, sink, and pore water velocity. Results show that the presence of sink, mimicked by plant-root uptake activity, and decay tend to reduce the solute concentration in the medium. While both the retardation and sorption factors affect the movement of the dissolved solutes, water content and pore-water velocity promote the spreading of dissolved solutes. Solute concentration in the medium increases at low Peclet numbers, signifying the influence of diffusive coefficients. The current proposed RITM-based solutions can characterize contamination in the soil, and should be useful to environmental researchers.

IDENTIFICATION OF GEOMECHANICAL AND GEOTECHNICAL STRUCTURES USING THE VIBROACOUSTIC METHOD FOR AUTOMATED STABILITY MONITORING SYSTEMS OF GROUND BUILDINGS AND MINE WORKINGS

Purpose. Identification of geomechanical and geotechnical structures by vibroacoustic method to improve reliability and automation level of ground buildings and mine working stability monitoring. Methods. Classical wave theory, experimental studies in laboratory and field conditions. Results. The most important feature of acoustic wave propagation in fractured media is the complexity of the wave pattern, since at each boundary between adjacent layers four new waves are formed – two reflected (longitudinal and transverse) and two refracted, each of them, when falling on another boundary, will cause a similar process. In the near-surface layer, classical acoustic waveguides are formed – sections of rock limited in one or two directions by voids, cracks or other media. As a result, the divergence of waves to the sides is eliminated or reduced, so their propagation along the layers occurs with less attenuation than in an unbounded homogeneous or inhomogeneous medium. To control elements of geomechanical and geotechnical structures, normal waves (modes) propagated in such acoustic waveguides without changing their structure should be used. When upper limit of the frequency range for recording acoustic signal of the response of a plane-parallel or block structure to the applied shock is lowered, the range of possible sounding bases expands. Within this range, the first mode of normal resonant oscillations is registered, and its limits shift towards an increase of the absolute value. The identification of geomechanical and geotechnical structures for systems of automated vibroacoustic control of stability of the mine workings was carried out. Originality. It is established that system control is ensured by identifying local geomechanical objects as the systems with lumped parameters, and changes in the load of the system elements should be controlled by analyzing the compliance between parameters of the system’s response to the exciting stimulation and the quasi-stationary criterion. In contrast to the known methods, automated control should be carried out with taking into account the stages of the oscillatory process development. Practical implications. The research results contribute to improvement of reliability and automation of the ground buildings and mine working stability monitoring. Keywords: vibroacoustic methods, identification of geomechanical structures, ground buildings and mine workings stability, automation of mine workings stability monitoring.

Entropy production with the flow of nanomaterials through the permeable stretched surface with heterogeneous-homogenous chemical reaction.

In various thermodynamic procedures and the optimisation of thermal manipulation, nanofluids flowing through porous media represent an emerging perspective. The main objective of this study, from the perspective of thermal applications, was the investigation of the flow of nanofluid over a horizontal stretched surface embedded in a porous medium. The effects of the chemical reactions on the surface, magnetic field, and thermal radiations were invoked in the mathematical formulation. The non-Darcy model examines the fluid flow in the porous media. The principles of thermodynamics were employed to integrate entropy optimisation methods with the established theoretical approach to analyse the thermal behaviour of nanomaterials in the chemical reactive diffusion processes. Using the Tiwari-Das nanofluid model, the volume fraction of the nanomaterials was merged in the mathematical equation for the flow model. Water was taken as a base fluid and nanoparticles composed of aluminium oxide (Al2O3) and silver (Ag) were used. The significance of radiation, heat production, and ohmic heating were included in the energy equation. Furthermore, an innovative mathematical model for the diffusion of the autocatalytic reactive species in the boundary layer flow was developed for a linear horizontally stretched surface embedded in a homogeneous non-Darcy porous medium saturated with the nanofluid. The computer-based built-in bvp5c method was used to compute numerically these equations for varied parameters. It is clear that the magnetic parameter has a reversal influence on the entropy rate and velocity. Temperature and velocity are affected in the opposite direction from a higher volume fraction estimate. Thermal field and entropy were increased when the radiation action intensified. The inclusion of nanoparticle fraction by the volume fraction of nanoparticles and Brinkman number also enhances the system entropy. Entropy production can be minimized with the involvement of the porosity factor within the surface.