International Journal of Numerical Methods for Heat & Fluid Flow最新文献

{"title":"Casson-Williamson ternary hybrid nanofluid flow over a yawed cylinder with the impacts of multiple slips","authors":"Prabhugouda Mallanagouda Patil, Bharath Goudar, Ebrahim Momoniat","doi":"10.1108/hff-03-2024-0176","DOIUrl":"https://doi.org/10.1108/hff-03-2024-0176","url":null,"abstract":"<h3>Purpose</h3>\u0000<p>Many industries use non-Newtonian ternary hybrid nanofluids (THNF) because of how well they control rheological and heat transport. This being the case, this paper aims to numerically study the Casson-Williamson THNF flow over a yawed cylinder, considering the effects of several slips and an inclined magnetic field. The THNF comprises Al<sub>2</sub>O<sub>3</sub>-TiO<sub>2</sub>-SiO<sub>2</sub> nanoparticles because they improve heat transmission due to large thermal conductivity.</p><!--/ Abstract__block -->\u0000<h3>Design/methodology/approach</h3>\u0000<p>Applying suitable nonsimilarity variables transforms the coupled highly dimensional nonlinear partial differential equations (PDEs) into a system of nondimensional PDEs. To accomplish the goal of achieving the solution, an implicit finite difference approach is used in conjunction with Quasilinearization. With the assistance of a script written in MATLAB, the numerical results and the graphical representation of those solutions were ascertained.</p><!--/ Abstract__block -->\u0000<h3>Findings</h3>\u0000<p>As the Casson parameter <span>\u0000<mml:math display=\"inline\" xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></span> increases, there is an improvement in the velocity profiles in both chord and span orientations, while the gradients <span>\u0000<mml:math display=\"inline\" xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mrow><mml:mi>R</mml:mi><mml:msup><mml:mi>e</mml:mi><mml:mrow><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:msup><mml:msub><mml:mi>C</mml:mi><mml:mi>f</mml:mi></mml:msub><mml:mo>,</mml:mo><mml:mtext> </mml:mtext><mml:mi>R</mml:mi><mml:msup><mml:mi>e</mml:mi><mml:mrow><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:msup><mml:msub><mml:mover accent=\"true\"><mml:mi>C</mml:mi><mml:mo>¯</mml:mo></mml:mover><mml:mi>f</mml:mi></mml:msub></mml:mrow></mml:math></span> reduce for the same variations of <span>\u0000<mml:math display=\"inline\" xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mi>β</mml:mi></mml:math></span>. The velocities of Casson THNF are greater than those of Casson-Williamson THNF. Approximately, a 202% and a 32% ascension are remarked in the magnitudes of <span>\u0000<mml:math display=\"inline\" xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mrow><mml:mi>R</mml:mi><mml:msup><mml:mi>e</mml:mi><mml:mrow><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:msup><mml:msub><mml:mi>C</mml:mi><mml:mi>f</mml:mi></mml:msub></mml:mrow></mml:math></span> and <span>\u0000<mml:math display=\"inline\" xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"><mml:mrow><mml:mi>R</mml:mi><mml:msup><mml:mi>e</mml:mi><mml:mrow><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:msup><mml:msub><mml:mover accent=\"true\"><mml:mi>C</mml:mi><mml:mo>¯</mml:mo></mml:mover><mml:mi>f</mml:mi></mml:msub></mml:mrow></mml:math></span> for Casson-Williamson THNF than the Casson THNF only. When velocity slip attribute ","PeriodicalId":14263,"journal":{"name":"International Journal of Numerical Methods for Heat & Fluid Flow","volume":"13 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142276056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermally radiative nanofluid heat transfer analysis inside a closed chamber with gyrotactic microorganisms","authors":"Paluru Sreedevi, P. Sudarsana Reddy","doi":"10.1108/hff-02-2024-0146","DOIUrl":"https://doi.org/10.1108/hff-02-2024-0146","url":null,"abstract":"<h3>Purpose</h3>\u0000<p>This paper aims to numerically examine the impact of gyrotactic microorganisms and radiation on heat transport features of magnetic nanoliquid within a closed cavity. Thermophoresis, chemical reaction and Brownian motion are also considered in flow geometry for the moment of nanoparticles.</p><!--/ Abstract__block -->\u0000<h3>Design/methodology/approach</h3>\u0000<p>Finite element method (FEM) was depleted to numerically approximate the temperature, momentum, concentration and microorganisms concentration of the nanoliquid. The present simulation was unsteady state, and the resulting transformed equations are simulated by FEM-based Mathematica algorithm.</p><!--/ Abstract__block -->\u0000<h3>Findings</h3>\u0000<p>It has been found that isotherm patterns get larger with increasing values of the magnetic field parameter. Additionally, numerical codes for rate of heat transport impedance inside the cavity with an increasing Brownian motion parameter values.</p><!--/ Abstract__block -->\u0000<h3>Originality/value</h3>\u0000<p>To the best of the authors’ knowledge, the research work carried out in this paper is new, and no part is copied from others’ works.</p><!--/ Abstract__block -->","PeriodicalId":14263,"journal":{"name":"International Journal of Numerical Methods for Heat & Fluid Flow","volume":"37 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142276073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational study on cilia transport of Prandtl nanofluid (blood-Fe3O4) enhancing convective heat transfer along microorganisms under electroosmotic effects in wavy capillaries","authors":"Madiha Ajmal, Rashid Mehmood, Noreen Sher Akbar, Taseer Muhammad","doi":"10.1108/hff-07-2024-0503","DOIUrl":"https://doi.org/10.1108/hff-07-2024-0503","url":null,"abstract":"<h3>Purpose</h3>\u0000<p>This study aims to focuse on the flow behavior of a specific nanofluid composed of blood-based iron oxide nanoparticles, combined with motile gyrotactic microorganisms, in a ciliated channel with electroosmosis.</p><!--/ Abstract__block -->\u0000<h3>Design/methodology/approach</h3>\u0000<p>This study applies a powerful mathematical model to examine the combined impacts of bio convection and electrokinetic forces on nanofluid flow. The presence of cilia, which are described as wave-like motions on the channel walls, promotes fluid propulsion, which improves mixing and mass transport. The velocity and dispersion of nanoparticles and microbes are modified by the inclusion of electroosmosis, which is stimulated by an applied electric field. This adds a significant level of complexity.</p><!--/ Abstract__block -->\u0000<h3>Findings</h3>\u0000<p>To ascertain their impact on flow characteristics, important factors such as bio convection Rayleigh number, Grashoff number, Peclet number and Lewis number are varied. The results demonstrate that while the gyrotactic activity of microorganisms contributes to the stability and homogeneity of the nanofluid distribution, electroosmotic forces significantly enhance fluid mixing and nanoparticle dispersion. This thorough study clarifies how to take advantage of electroosmosis and bio convection in ciliated micro channels to optimize nanofluid-based biomedical applications, such as targeted drug administration and improved diagnostic processes.</p><!--/ Abstract__block -->\u0000<h3>Originality/value</h3>\u0000<p>First paper discussed “Numerical Computation of Cilia Transport of Prandtl Nanofluid (Blood-Fe₃O₄) Enhancing Convective Heat Transfer along Micro Organisms under Electroosmotic effects in Wavy Capillaries”.</p><!--/ Abstract__block -->","PeriodicalId":14263,"journal":{"name":"International Journal of Numerical Methods for Heat & Fluid Flow","volume":"243 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142234508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Monotonic unbounded schemes transformer (MUST): an approach to remove undershoots and overshoots in family of unbounded schemes using finite-volume method","authors":"Y.F. Yap, J.C. Chai","doi":"10.1108/hff-04-2024-0293","DOIUrl":"https://doi.org/10.1108/hff-04-2024-0293","url":null,"abstract":"<h3>Purpose</h3>\u0000<p>This paper presents a Monotonic Unbounded Schemes Transformer (MUST) approach to bound/monotonize (remove undershoots and overshoots) unbounded spatial differencing schemes automatically, and naturally. Automatically means the approach (1) captures the critical cell Peclet number when an unbounded scheme starts to produce physically unrealistic solution automatically, and (2) removes the undershoots and overshoots as part of the formulation without requiring human interventions. Naturally implies, all the terms in the discretization equation of the unbounded spatial differencing scheme are retained.</p><!--/ Abstract__block -->\u0000<h3>Design/methodology/approach</h3>\u0000<p>The authors do not formulate new higher-order scheme. MUST transforms an unbounded higher-order scheme into a bounded higher-order scheme.</p><!--/ Abstract__block -->\u0000<h3>Findings</h3>\u0000<p>The solutions obtained with MUST are identical to those without MUST when the cell Peclet number is smaller than the critical cell Peclet number. For cell Peclet numbers larger than the critical cell Peclet numbers, MUST sets the nodal values to the limiter value which can be derived for the problem at-hand. The authors propose a way to derive the limiter value. The authors tested MUST on the central differencing scheme, the second-order upwind differencing scheme and the QUICK differencing scheme. In all cases tested, MUST is able to (1) capture the critical cell Peclet numbers; the exact locations when overshoots and undershoots occur, and (2) limit the nodal value to the value of the limiter values. These are achieved by retaining all the discretization terms of the respective differencing schemes naturally and accomplished automatically as part of the discretization process. The authors demonstrated MUST using one-dimensional problems. Results for a two-dimensional convection–diffusion problem are shown in Appendix to show generality of MUST.</p><!--/ Abstract__block -->\u0000<h3>Originality/value</h3>\u0000<p>The authors present an original approach to convert any unbounded scheme to bounded scheme while retaining all the terms in the original discretization equation.</p><!--/ Abstract__block -->","PeriodicalId":14263,"journal":{"name":"International Journal of Numerical Methods for Heat & Fluid Flow","volume":"14 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142234471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetohydrodynamic double diffusion natural convection of power-law Non-Newtonian Nano-Encapsulated phase change materials in a trapezoidal enclosure","authors":"Khairunnahar Suchana, Md. Mamun Molla","doi":"10.1108/hff-02-2024-0170","DOIUrl":"https://doi.org/10.1108/hff-02-2024-0170","url":null,"abstract":"&lt;h3&gt;Purpose&lt;/h3&gt;\u0000&lt;p&gt;The present numerical investigation examines the magnetohydrodynamic (MHD) double diffusion natural convection of power-law non-Newtonian nano-encapsulated phase change materials (NEPCMs) in a trapezoidal cavity.&lt;/p&gt;&lt;!--/ Abstract__block --&gt;\u0000&lt;h3&gt;Design/methodology/approach&lt;/h3&gt;\u0000&lt;p&gt;The governing Navier-Stokes, energy and concentration equations based on the Cartesian curvilinear coordinates are solved using the collocated grid arrangement’s finite volume method. The in-house FORTRAN code is validated with the different benchmark problems. The NEPCM nanoparticles consist of a core-shell structure with Phase Change Material (PCM) at the core. The enclosure, shaped as a trapezoidal hollow, features a warmed (&lt;em&gt;T&lt;sub&gt;h&lt;/sub&gt;&lt;/em&gt;) left wall and a cold (&lt;em&gt;T&lt;sub&gt;c&lt;/sub&gt;&lt;/em&gt;) right wall. Various parameters are considered, including the power law index (0.6 ≤ &lt;em&gt;n&lt;/em&gt; ≤ 1.4), Hartmann number (0 ≤ &lt;em&gt;Ha&lt;/em&gt; ≤ 30), Rayleigh number (10&lt;sup&gt;4&lt;/sup&gt; ≤ &lt;em&gt;Ra&lt;/em&gt; ≤ 10&lt;sup&gt;5&lt;/sup&gt;) and fixed variables such as buoyancy ratio (&lt;em&gt;Br&lt;/em&gt; = 0.8), Prandtl number (&lt;em&gt;Pr&lt;/em&gt; = 6.2), Lewis number (&lt;em&gt;Le&lt;/em&gt; = 5), fusion temperature (Θ&lt;sub&gt;&lt;em&gt;f&lt;/em&gt;&lt;/sub&gt; = 0.5) and volume fraction (ϕ = 0.04).&lt;/p&gt;&lt;!--/ Abstract__block --&gt;\u0000&lt;h3&gt;Findings&lt;/h3&gt;\u0000&lt;p&gt;The findings indicate a decrease in local Nusselt (&lt;em&gt;Nu&lt;/em&gt;) and Sherwood (&lt;em&gt;Sh&lt;/em&gt;) numbers with increasing Hartmann numbers (&lt;em&gt;Ha&lt;/em&gt;). Additionally, for a shear-thinning fluid (&lt;em&gt;n&lt;/em&gt; = 0.6) results in the maximum local &lt;em&gt;Nu&lt;/em&gt; and &lt;em&gt;Sh&lt;/em&gt; values. As the Rayleigh number (&lt;em&gt;Ra&lt;/em&gt;) increases from 10&lt;sup&gt;4&lt;/sup&gt; to 10&lt;sup&gt;5&lt;/sup&gt;, the structured vortex in the streamline pattern is disturbed. Furthermore, for different &lt;em&gt;Ra&lt;/em&gt; values, an increase in &lt;em&gt;n&lt;/em&gt; from 0.6 to 1.4 leads to a 67.43% to 76.88% decrease in average &lt;em&gt;Nu&lt;/em&gt; and a 70% to 77% decrease in average &lt;em&gt;Sh&lt;/em&gt;.&lt;/p&gt;&lt;!--/ Abstract__block --&gt;\u0000&lt;h3&gt;Research limitations/implications&lt;/h3&gt;\u0000&lt;p&gt;This research is for two-dimensioal laminar flow only.&lt;/p&gt;&lt;!--/ Abstract__block --&gt;\u0000&lt;h3&gt;Practical implications&lt;/h3&gt;\u0000&lt;p&gt;PCMs represent a class of practical substances that behave as a function of temperature and have the innate ability to absorb, release and store heated energy in the form of hidden fusion enthalpy, or heat. They are valuable in these systems as they can store significant energy at a relatively constant temperature through their latent heat phase change.&lt;/p&gt;&lt;!--/ Abstract__block --&gt;\u0000&lt;h3&gt;Originality/value&lt;/h3&gt;\u0000&lt;p&gt;As per the literature review and the authors’ understanding, an examination has never been conducted on MHD double diffusion natural convection of power-law non-Newtonian NEPCMs within a trapezoidal enclosure. The current work is innovative since it combines NEPCMs with the effect of magnetic field Double diffusion Natural Convection of power-law non-Newtonian NEPCMs in a Trapezoidal enclosure. This outcome can be used to improve thermal management in energy storage systems, increasing safety","PeriodicalId":14263,"journal":{"name":"International Journal of Numerical Methods for Heat & Fluid Flow","volume":"52 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142170867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bright and dark optical solitons in optical metamaterials using a variety of distinct schemes for a generalized Schrodinger equation","authors":"Suheil Khuri, Abdul-Majid Wazwaz","doi":"10.1108/hff-05-2024-0408","DOIUrl":"https://doi.org/10.1108/hff-05-2024-0408","url":null,"abstract":"<h3>Purpose</h3>\u0000<p>The purpose of this study is to investigate the nonlinear Schrödinger equation (NLS) incorporating spatiotemporal dispersion and other dispersive effects. The goal is to derive various soliton solutions, including bright, dark, singular, periodic and exponential solitons, to enhance the understanding of soliton propagation dynamics in nonlinear metamaterials (MMs) and contribute new findings to the field of nonlinear optics.</p><!--/ Abstract__block -->\u0000<h3>Design/methodology/approach</h3>\u0000<p>The research uses a range of powerful mathematical approaches to solve the NLS. The proposed methodologies are applied systematically to derive a variety of optical soliton solutions, each demonstrating unique optical behaviors and characteristics. The approach ensures that both the theoretical framework and practical implications of the solutions are thoroughly explored.</p><!--/ Abstract__block -->\u0000<h3>Findings</h3>\u0000<p>The study successfully derives several types of soliton solutions using the aforementioned mathematical approaches. Key findings include bright optical envelope solitons, dark optical envelope solitons, periodic solutions, singular solutions and exponential solutions. These results offer new insights into the behavior of ultrashort solitons in nonlinear MMs, potentially aiding further research and applications in nonlinear wave studies.</p><!--/ Abstract__block -->\u0000<h3>Originality/value</h3>\u0000<p>This study makes an original contribution to nonlinear optics by deriving new soliton solutions for the NLS with spatiotemporal dispersion. The diversity of solutions, including bright, dark, periodic, singular and exponential solitons, adds substantial value to the existing body of knowledge. The use of distinct and reliable methodologies to obtain these solutions underscores the novelty and potential applications of the research in advancing optical technologies. The originality lies in the novel approaches used to obtain these diverse soliton solutions and their potential impact on the study and application of nonlinear waves in MMs.</p><!--/ Abstract__block -->","PeriodicalId":14263,"journal":{"name":"International Journal of Numerical Methods for Heat & Fluid Flow","volume":"6 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142166245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study on the behavior of a polymeric MHD nanofluid: entropy optimization and thermal analysis","authors":"Razi Khan","doi":"10.1108/hff-02-2024-0144","DOIUrl":"https://doi.org/10.1108/hff-02-2024-0144","url":null,"abstract":"<h3>Purpose</h3>\u0000<p>Analyzing and reducing entropy generation is useful for enhancing the thermodynamic performance of engineering systems. This study aims to explore how polymers and nanoparticles in the presence of Lorentz forces influence the fluid behavior and heat transfer characteristics to lessen energy loss and entropy generation.</p><!--/ Abstract__block -->\u0000<h3>Design/methodology/approach</h3>\u0000<p>The dispersion model is initially used to examine the behavior of polymer additives over a magnetized surface. The governing system of partial differential equations (PDEs) is subsequently reduced through the utilization of similarity transformation techniques. Entropy analysis is primarily performed through the implementation of numerical computations on a non-Newtonian polymeric FENE-P model.</p><!--/ Abstract__block -->\u0000<h3>Findings</h3>\u0000<p>The numerical simulations conducted in the presence of Lorentz forces provide significant insights into the consequences of adding polymers to the base fluid. The findings suggest that such an approach minimizes entropy in the flow region. Through the utilization of polymer-MHD (magnetohydrodynamic) interactions, it is feasible to reduce energy loss and improve the efficiency of the system.</p><!--/ Abstract__block -->\u0000<h3>Originality/value</h3>\u0000<p>This study’s primary motivation and novelty lie in examining the significance of polymer additives as agents that reduce entropy generation on a magnetic surface. The author looks at how nanofluids affect the development of entropy and the loss of irreversibility. To do this, the author uses the Lorentz force, the Soret effect and the Dufour effect to minimize entropy. The findings contribute to fluid mechanics and thermodynamics by providing valuable insights for engineering systems to increase energy efficiency and conserve resources.</p><!--/ Abstract__block -->","PeriodicalId":14263,"journal":{"name":"International Journal of Numerical Methods for Heat & Fluid Flow","volume":"133 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142158798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Finite element method (FEM) analysis of heat transfer by natural convection in a circular cavity containing a corrugated hollow cylinder","authors":"Abdelhak Daiz, Rachid Hidki, Redouane Fares, Zouhair Charqui","doi":"10.1108/hff-04-2024-0292","DOIUrl":"https://doi.org/10.1108/hff-04-2024-0292","url":null,"abstract":"<h3>Purpose</h3>\u0000<p>The purpose of this study is to analyze the free convection phenomena arising from a temperature disparity between a cold circular cylinder and a heated corrugated cylinder.</p><!--/ Abstract__block -->\u0000<h3>Design/methodology/approach</h3>\u0000<p>Numerical simulations were used to analyze the convection patterns. The inner cylinder, made of a thermally conductive solid material, was heated through its inner surface, while the space between the cylinders was filled with air. The governing equations for velocity, pressure and temperature were solved using a Galerkin finite element method-based solver for partial differential equations.</p><!--/ Abstract__block -->\u0000<h3>Findings</h3>\u0000<p>The study explored various parameters affecting the dynamic and thermal structure of the flow, including the Rayleigh number (10³ ≤ Ra ≤ 10⁶), the number of corrugations of the inner cylinder (3 ≤ <em>N</em> ≤ 18), the thermal conductivity of the hollow cylinder (1 ≤ <em>K</em> ≤ 200) and the angle of inclination of the inner cylinder (0° ≤ <em>φ</em> ≤ 90°). Results indicated a notable sensitivity of flow intensity to changes in the Rayleigh number and the inner cylinder’s inclination angle <em>φ</em>. Particularly, for Ra = 10⁶, the average heat transfer rate increased by 203% with a <em>K</em> ratio increment from 1 to 100 but decreased by 16.3% as the number of corrugations increased from 3 to 18.</p><!--/ Abstract__block -->\u0000<h3>Originality/value</h3>\u0000<p>This research contributes to understanding the complex interplay between geometry, thermal properties and flow dynamics in natural convection systems involving cylindrical geometries. The findings offer useful insights for improving the transfer of heat procedures in real-world situations.</p><!--/ Abstract__block -->","PeriodicalId":14263,"journal":{"name":"International Journal of Numerical Methods for Heat & Fluid Flow","volume":"38 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142131003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal radiation, Soret and Dufour effects on MHD mixed convective Maxwell hybrid nanofluid flow under porous medium: a numerical study","authors":"J. Jayaprakash, Vediyappan Govindan, S.S. Santra, S.S. Askar, Abdelaziz Foul, Susmay Nandi, Syed Modassir Hussain","doi":"10.1108/hff-03-2024-0229","DOIUrl":"https://doi.org/10.1108/hff-03-2024-0229","url":null,"abstract":"<h3>Purpose</h3>\u0000<p>Scientists have been conducting trials to find ways to reduce fuel consumption and enhance heat transfer rates to make heating systems more efficient and cheaper. Adding solid nanoparticles to conventional liquids may greatly improve their thermal conductivity, according to the available evidence. This study aims to examine the influence of external magnetic flux on the flow of a mixed convective Maxwell hybrid non-Newtonian nanofluid over a linearly extending porous flat plate. The investigation considers the effects of thermal radiation, Dufour and Soret.</p><!--/ Abstract__block -->\u0000<h3>Design/methodology/approach</h3>\u0000<p>The mathematical model is formulated based on the fundamental assumptions of mass, energy and momentum conservation. The implicit models are epitomized by a set of interconnected nonlinear partial differential equations, which include a suitable and comparable adjustment. The numerical solution to these equations is assessed for approximate convergence by the Runge−Kutta−Fehlberg method based on the shooting technique embedded with the MATLAB software.</p><!--/ Abstract__block -->\u0000<h3>Findings</h3>\u0000<p>The findings are presented through graphical representations, offering a visual exploration of the effects of various dynamic parameters on the flow field. These parameters encompass a wide range of factors, including radiation, thermal and Brownian diffusion parameters, Eckert, Lewis and Soret numbers, magnetic parameters, Maxwell fluid parameters, Darcy numbers, thermal and solutal buoyancy factors, Dufour and Prandtl numbers. Notably, the authors observed that nanoparticles with a spherical shape exerted a significant influence on the stream function, highlighting the importance of nanoparticle geometry in fluid dynamics. Furthermore, the analysis revealed that temperature profiles of nanomaterials were notably affected by their shape factor, while concentration profiles exhibited an opposite trend, providing valuable insights into the behavior of nanofluids in porous media.</p><!--/ Abstract__block -->\u0000<h3>Originality/value</h3>\u0000<p>A distinctive aspect of the research lies in its novel exploration of the impact of external magnetic flux on the flow of a mixed convective Maxwell hybrid non-Newtonian nanofluid over a linearly extending porous flat plate. By considering variables such as solar radiation, external magnetic flux, thermal and Brownian diffusion parameters and nanoparticle shape factor, the authors ventured into uncharted territory within the realm of fluid dynamics. These variables, despite their significant relevance, have not been extensively studied in previous research, thus underscoring the originality and value of the authors’ contribution to the field.</p><!--/ Abstract__block -->","PeriodicalId":14263,"journal":{"name":"International Journal of Numerical Methods for Heat & Fluid Flow","volume":"36 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142118070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel localized waves and dynamics analysis for a generalized (3+1)-dimensional breaking soliton equation","authors":"Jingfeng Quan, Xiaoyan Tang","doi":"10.1108/hff-04-2024-0298","DOIUrl":"https://doi.org/10.1108/hff-04-2024-0298","url":null,"abstract":"<h3>Purpose</h3>\u0000<p>This paper aims to explore new variable separation solutions for a new generalized (3 + 1)-dimensional breaking soliton equation, construct novel nonlinear excitations and discuss their dynamical behaviors that may exist in many realms such as fluid dynamics, optics and telecommunication.</p><!--/ Abstract__block -->\u0000<h3>Design/methodology/approach</h3>\u0000<p>By means of the multilinear variable separation approach, variable separation solutions for the new generalized (3 + 1)-dimensional breaking soliton equation are derived with arbitrary low dimensional functions with respect to {<em>y</em>, <em>z</em>, <em>t</em>}. The asymptotic analysis is presented to represent generally the evolutions of rogue waves.</p><!--/ Abstract__block -->\u0000<h3>Findings</h3>\u0000<p>Fixing several types of explicit expressions of the arbitrary function in the potential field U, various novel nonlinear wave excitations are fabricated, such as hybrid waves of kinks and line solitons with different structures and other interesting characteristics, as well as interacting waves between rogue waves, kinks, line solitons with translation and rotation.</p><!--/ Abstract__block -->\u0000<h3>Research limitations/implications</h3>\u0000<p>The paper presents that a variable separation solution with an arbitrary function of three independent variables has great potential to describe localized waves.</p><!--/ Abstract__block -->\u0000<h3>Practical implications</h3>\u0000<p>The roles of parameters in the chosen functions are ascertained in this study, according to which, one can understand the amplitude, shape, background and other characteristics of the localized waves.</p><!--/ Abstract__block -->\u0000<h3>Social implications</h3>\u0000<p>The work provides novel localized waves that might be used to explain some nonlinear phenomena in fluids, plasma, optics and so on.</p><!--/ Abstract__block -->\u0000<h3>Originality/value</h3>\u0000<p>The study proposes a new generalized (3 + 1)-dimensional breaking soliton equation and derives its nonlinear variable separation solutions. It is demonstrated that a variable separation solution with an arbitrary function of three independent variables provides a treasure-house of nonlinear waves.</p><!--/ Abstract__block -->","PeriodicalId":14263,"journal":{"name":"International Journal of Numerical Methods for Heat & Fluid Flow","volume":"51 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142101977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}