Pub Date : 2023-11-03DOI: 10.1142/s0217984924501008
Shajar Abbas, Mudassar Nazar, Syeda Farzeen Fatima Gillani, Muhammad Naveed, Mushtaq Ahmad, Zaib Un Nisa
A fractional technique is used to evaluate the temperature, mass, and velocity flow of single and double wall CNTs over a vertical plate. Slip boundary conditions and applied magnetic force are addressed. Human blood is used to examine how base fluid behaves. Applying the proper dimensionless variables results in the dimensionless formulation of initial and boundary conditions related to the governed dimensional concentration, momentum, and energy equations. The Laplace transform technique is used to resolve the dimensionless governing partial differential equations and get the solutions. The constant proportional Caputo (CPC) time-fractional derivative is a unique class of fractional model used in the simulation technique. The fundamental definitions are used to support the said model first. Using MWCNTs and SWCNTs in comparison to the flow characteristics, a thermal and mass study is given. The heat and mass transfer processes for single-walled carbon nanotubes (SWCNTs) have been shown to typically be progressive. The momentum profile decreases as the fractional variables rise. Multi-walled carbon nanotubes (MWCNTs) show more progressive velocity control as a result of the magnetic parameter. Graphs demonstrate the influence of embedding factors on the velocity, energy, and concentration profiles.
{"title":"A CPC fractional model of the heat and mass transport mechanism in Carbon nanotubes with slip effects on velocity","authors":"Shajar Abbas, Mudassar Nazar, Syeda Farzeen Fatima Gillani, Muhammad Naveed, Mushtaq Ahmad, Zaib Un Nisa","doi":"10.1142/s0217984924501008","DOIUrl":"https://doi.org/10.1142/s0217984924501008","url":null,"abstract":"A fractional technique is used to evaluate the temperature, mass, and velocity flow of single and double wall CNTs over a vertical plate. Slip boundary conditions and applied magnetic force are addressed. Human blood is used to examine how base fluid behaves. Applying the proper dimensionless variables results in the dimensionless formulation of initial and boundary conditions related to the governed dimensional concentration, momentum, and energy equations. The Laplace transform technique is used to resolve the dimensionless governing partial differential equations and get the solutions. The constant proportional Caputo (CPC) time-fractional derivative is a unique class of fractional model used in the simulation technique. The fundamental definitions are used to support the said model first. Using MWCNTs and SWCNTs in comparison to the flow characteristics, a thermal and mass study is given. The heat and mass transfer processes for single-walled carbon nanotubes (SWCNTs) have been shown to typically be progressive. The momentum profile decreases as the fractional variables rise. Multi-walled carbon nanotubes (MWCNTs) show more progressive velocity control as a result of the magnetic parameter. Graphs demonstrate the influence of embedding factors on the velocity, energy, and concentration profiles.","PeriodicalId":18570,"journal":{"name":"Modern Physics Letters B","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135873441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-03DOI: 10.1142/s0217984924501173
Yu. V. Knyazev, A. V. Lukoyanov, Yu. I. Kuz’min
The optical properties of bulk AuCu 3 -type ordered superconducting binary compounds ScGa 3 and LuGa 3 have been experimentally investigated for the first time in the wide spectral range and explained in terms of the band structure. First-principles calculations of electronic densities of states and optical conductivities are performed within the framework of LSDA+U method using the LMTO-ASA software package. The measured dielectric functions spectra for both materials exhibit a strong absorption region above ∼ 1[Formula: see text]eV, which are in a reasonable agreement with the calculated metal-like energy structures of compounds. Features of quantum light absorption are discussed on the basis of a comparative analysis of experimental and theoretical spectra of interband optical conductivity. Plasma and relaxation frequencies of conduction electrons are determined.
{"title":"Electronic structure and optical properties of superconducting compounds ScGa<sub>3</sub> and LuGa<sub>3</sub>","authors":"Yu. V. Knyazev, A. V. Lukoyanov, Yu. I. Kuz’min","doi":"10.1142/s0217984924501173","DOIUrl":"https://doi.org/10.1142/s0217984924501173","url":null,"abstract":"The optical properties of bulk AuCu 3 -type ordered superconducting binary compounds ScGa 3 and LuGa 3 have been experimentally investigated for the first time in the wide spectral range and explained in terms of the band structure. First-principles calculations of electronic densities of states and optical conductivities are performed within the framework of LSDA+U method using the LMTO-ASA software package. The measured dielectric functions spectra for both materials exhibit a strong absorption region above ∼ 1[Formula: see text]eV, which are in a reasonable agreement with the calculated metal-like energy structures of compounds. Features of quantum light absorption are discussed on the basis of a comparative analysis of experimental and theoretical spectra of interband optical conductivity. Plasma and relaxation frequencies of conduction electrons are determined.","PeriodicalId":18570,"journal":{"name":"Modern Physics Letters B","volume":"27 24","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135873442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-03DOI: 10.1142/s0217984924500982
Reem K. Alhefthi, Y. Vinod, K. R. Raghunatha, G. Pallavi, Mustafa Inc
The combined heat and mass transfer, the so-called thermosolutal convective problem, has become an attractive field of research in many diversified areas. In this paper, for the first time, oscillatory flow analysis has been carried out for triple diffusive viscoelastic fluid flow in a porous medium. A comprehensive model is developed for the modified Darcy–Brinkman–Oldroyd-B fluid, porous medium, Boussinesq approximation, heat and mass transfer across a finite temperature and concentration difference in the chemical potential of two salts. Triple diffusive viscoelastic fluid flows through porous media have grown significantly as this situation occurs in more than a few applications such as improved oil recovery filtration, liquid complex molding, solidification of liquid crystals, cooling of metallic plate in a bath, exotic lubricants and colloidal solutions, polymer processing, chemical and bioengineering industries, among others. The governing coupled nonlinear partial differential equations with boundary constraints represent the modeled flow problem. In addition, these equations are converted into non-dimensional form by employing suitable non-dimensionalizing quantities. The impacts of the pertinent parameters and related dimensionless numbers on the dimensionless velocity, temperature, concentrations, shear stress, heat and mass transfer are examined for both suction and injection cases. It has been found that when the injection level on the heated plate is increased, the shear rate increases for each channel plate. Furthermore, we recognized that the viscoelastic parameters exhibit an opposite kind of behavior on the velocity, temperature, and concentrations fields.
{"title":"Viscoelastic effect on the triple diffusive oscillatory flow in a fluid-saturated porous layer","authors":"Reem K. Alhefthi, Y. Vinod, K. R. Raghunatha, G. Pallavi, Mustafa Inc","doi":"10.1142/s0217984924500982","DOIUrl":"https://doi.org/10.1142/s0217984924500982","url":null,"abstract":"The combined heat and mass transfer, the so-called thermosolutal convective problem, has become an attractive field of research in many diversified areas. In this paper, for the first time, oscillatory flow analysis has been carried out for triple diffusive viscoelastic fluid flow in a porous medium. A comprehensive model is developed for the modified Darcy–Brinkman–Oldroyd-B fluid, porous medium, Boussinesq approximation, heat and mass transfer across a finite temperature and concentration difference in the chemical potential of two salts. Triple diffusive viscoelastic fluid flows through porous media have grown significantly as this situation occurs in more than a few applications such as improved oil recovery filtration, liquid complex molding, solidification of liquid crystals, cooling of metallic plate in a bath, exotic lubricants and colloidal solutions, polymer processing, chemical and bioengineering industries, among others. The governing coupled nonlinear partial differential equations with boundary constraints represent the modeled flow problem. In addition, these equations are converted into non-dimensional form by employing suitable non-dimensionalizing quantities. The impacts of the pertinent parameters and related dimensionless numbers on the dimensionless velocity, temperature, concentrations, shear stress, heat and mass transfer are examined for both suction and injection cases. It has been found that when the injection level on the heated plate is increased, the shear rate increases for each channel plate. Furthermore, we recognized that the viscoelastic parameters exhibit an opposite kind of behavior on the velocity, temperature, and concentrations fields.","PeriodicalId":18570,"journal":{"name":"Modern Physics Letters B","volume":"27 23","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135873443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-03DOI: 10.1142/s0217984923502512
Romaisa Iqbal, Malika Rani, Aqeel Ahmad Shah, Rabia Siddiqui, Alidad Chandio, Muhammad Nawaz Sharif, Waseem Abbas, M. Ajmal Khan
In this study, a novel Al-MOFs was hydrothermally synthesized using organic linker (benzene-1,3,5-tricarboxylic acid, i.e. trimesic acid) because of its thermal and chemical stability as well as the versatile capability of Aluminum (Al) to form multifaceted structures. The material was targeted for applications in supercapacitor, energy storage, sensing and biomedical sciences like Far-UVC device applications. The morphological structure and bandgap of the Benzene Tricarboxylic Acid (BTC)-Aluminum based MOFs samples underwent characterization using a range of techniques, such as X-ray Diffraction (XRD) analysis, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Raman spectroscopy, and UV–Vis spectroscopy. The XRD investigation confirmed the successful fabrication of MOF layered structure on Al-MOFs with an average crystallinity of 2.155[Formula: see text]nm. SEM identified the hexagonal structure of Al-MOFs nanocrystals and showed strong agglomeration with a grain size of 186[Formula: see text]nm. EDX analysis confirms the existence of aluminum peaks along with carbon peaks (as organic linkers), indicating the presence of organic linkers in the framework, which is the key component of MOF’s porosity. The Raman spectroscopy results evidenced the synthesis of Al-MOFs structure. The optical bandgap was evaluated using UV–Vis spectrophotometry and estimated as [Formula: see text][Formula: see text]eV, indicating the materials stability for photovoltaic and some Far-UVC devices. Overall, the results suggest that the synthesized Al-MOFs nanomaterial is a promising candidate for various applications including Far-UVC device applications.
{"title":"Facile synthesis and characterization of Al-MOFs using benzene-1,3,5-tricarboxylic acid as a new class of materials for Far-UVC applications","authors":"Romaisa Iqbal, Malika Rani, Aqeel Ahmad Shah, Rabia Siddiqui, Alidad Chandio, Muhammad Nawaz Sharif, Waseem Abbas, M. Ajmal Khan","doi":"10.1142/s0217984923502512","DOIUrl":"https://doi.org/10.1142/s0217984923502512","url":null,"abstract":"In this study, a novel Al-MOFs was hydrothermally synthesized using organic linker (benzene-1,3,5-tricarboxylic acid, i.e. trimesic acid) because of its thermal and chemical stability as well as the versatile capability of Aluminum (Al) to form multifaceted structures. The material was targeted for applications in supercapacitor, energy storage, sensing and biomedical sciences like Far-UVC device applications. The morphological structure and bandgap of the Benzene Tricarboxylic Acid (BTC)-Aluminum based MOFs samples underwent characterization using a range of techniques, such as X-ray Diffraction (XRD) analysis, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Raman spectroscopy, and UV–Vis spectroscopy. The XRD investigation confirmed the successful fabrication of MOF layered structure on Al-MOFs with an average crystallinity of 2.155[Formula: see text]nm. SEM identified the hexagonal structure of Al-MOFs nanocrystals and showed strong agglomeration with a grain size of 186[Formula: see text]nm. EDX analysis confirms the existence of aluminum peaks along with carbon peaks (as organic linkers), indicating the presence of organic linkers in the framework, which is the key component of MOF’s porosity. The Raman spectroscopy results evidenced the synthesis of Al-MOFs structure. The optical bandgap was evaluated using UV–Vis spectrophotometry and estimated as [Formula: see text][Formula: see text]eV, indicating the materials stability for photovoltaic and some Far-UVC devices. Overall, the results suggest that the synthesized Al-MOFs nanomaterial is a promising candidate for various applications including Far-UVC device applications.","PeriodicalId":18570,"journal":{"name":"Modern Physics Letters B","volume":"27 18","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135873448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, a three-point bending test was carried out to determine the mechanical properties of hexagonal-shaped honeycomb core sandwich panels made of jute yarn with two distinct fiber orientations. A custom-made handloom was used to weave the unidirectional jute mat, and hand-layup with the cold press process was applied to fabricate the hexagonal honeycomb sandwich panel. To explore the effectiveness of different natural fibers for producing honeycomb core sandwich panels, a Finite Element Method (FEM) analysis was performed on different natural fibers with different fiber orientations. The resistance to environmental deterioration of bending properties was also investigated. Overall, this work offers perceptive information about the mechanical characteristics of sandwich panels made of jute honeycomb core and their behavior under various climatic circumstances, which may be relevant in a variety of engineering applications. Finally, it is noteworthy that the mechanical properties of jute fibers are anisotropic, which implies that their strength varies with the direction of loading. Sandwich panels with horizontal fiber orientation of hexagonal honeycomb core withstand a 36% higher bending strength than those with vertical fiber orientation.
{"title":"Experimental investigation with FE analysis on flexural strength of hexagonal-shaped honeycomb sandwich panel","authors":"Fatema Ferdous, Md. Foisal Hossain, Muhammed Sohel Rana, Md. Shafiul Ferdous","doi":"10.1142/s0217984924500945","DOIUrl":"https://doi.org/10.1142/s0217984924500945","url":null,"abstract":"In this study, a three-point bending test was carried out to determine the mechanical properties of hexagonal-shaped honeycomb core sandwich panels made of jute yarn with two distinct fiber orientations. A custom-made handloom was used to weave the unidirectional jute mat, and hand-layup with the cold press process was applied to fabricate the hexagonal honeycomb sandwich panel. To explore the effectiveness of different natural fibers for producing honeycomb core sandwich panels, a Finite Element Method (FEM) analysis was performed on different natural fibers with different fiber orientations. The resistance to environmental deterioration of bending properties was also investigated. Overall, this work offers perceptive information about the mechanical characteristics of sandwich panels made of jute honeycomb core and their behavior under various climatic circumstances, which may be relevant in a variety of engineering applications. Finally, it is noteworthy that the mechanical properties of jute fibers are anisotropic, which implies that their strength varies with the direction of loading. Sandwich panels with horizontal fiber orientation of hexagonal honeycomb core withstand a 36% higher bending strength than those with vertical fiber orientation.","PeriodicalId":18570,"journal":{"name":"Modern Physics Letters B","volume":"27 15","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135873451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-03DOI: 10.1142/s0217984923502536
Elmira Sartipi, Seyed Mohammad Elahi, Mohammad Reza Hantehzadeh, Arash Boochani, Mahmood Ghoranneviss
The mechanical, electronic, magneto-optic and thermoelectric properties of CeBiPt compound have been calculated based on density functional theory (DFT) calculations. This compound has ground state point in the ferromagnetic phase with elastic stability by large bulk modulus of 88.565[Formula: see text]GPa. Poisson’s coefficient of 0.257 represents the ionic bonds between atoms, while the anisotropy coefficient indicates the elastic isotropic nature of this compound. Also, phonon dispersion emphasizes to the dynamic stability of this compound. By the mBJ approximation, this case exhibits ferromagnetic behavior with a magnetic moment of 0.98[Formula: see text][Formula: see text]. Based on the magnetic behavior of this crystal, the Kerr effect angles ([Formula: see text]) are 3.6 ∘ at 3[Formula: see text]eV and [Formula: see text] at 5.4[Formula: see text]eV, respectively, therefore, the rotation angle of the ellipse light polarization ([Formula: see text]) in the edge of ultraviolet region shows a large polarization of light in the visible region. The negative Seebeck coefficient of CeBiPt compound at low temperature refers to the hole transfer, also the magnitude of the power factor at higher temperatures indicates this compound is suitable for use in power generator applications.
{"title":"Giant magneto-optical Kerr effect and thermoelectric properties in CeBiPt half-Heusler by DFT","authors":"Elmira Sartipi, Seyed Mohammad Elahi, Mohammad Reza Hantehzadeh, Arash Boochani, Mahmood Ghoranneviss","doi":"10.1142/s0217984923502536","DOIUrl":"https://doi.org/10.1142/s0217984923502536","url":null,"abstract":"The mechanical, electronic, magneto-optic and thermoelectric properties of CeBiPt compound have been calculated based on density functional theory (DFT) calculations. This compound has ground state point in the ferromagnetic phase with elastic stability by large bulk modulus of 88.565[Formula: see text]GPa. Poisson’s coefficient of 0.257 represents the ionic bonds between atoms, while the anisotropy coefficient indicates the elastic isotropic nature of this compound. Also, phonon dispersion emphasizes to the dynamic stability of this compound. By the mBJ approximation, this case exhibits ferromagnetic behavior with a magnetic moment of 0.98[Formula: see text][Formula: see text]. Based on the magnetic behavior of this crystal, the Kerr effect angles ([Formula: see text]) are 3.6 ∘ at 3[Formula: see text]eV and [Formula: see text] at 5.4[Formula: see text]eV, respectively, therefore, the rotation angle of the ellipse light polarization ([Formula: see text]) in the edge of ultraviolet region shows a large polarization of light in the visible region. The negative Seebeck coefficient of CeBiPt compound at low temperature refers to the hole transfer, also the magnitude of the power factor at higher temperatures indicates this compound is suitable for use in power generator applications.","PeriodicalId":18570,"journal":{"name":"Modern Physics Letters B","volume":"28 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135873598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-03DOI: 10.1142/s0217984924500969
Priya Mathur, S. R. Mishra
The recent applications in industrial products and engineering need high thermal efficiency for the betterment of the shape of the products, the concept of hybrid nanofluid is significant in comparison to nanofluid and pure fluid. Therefore, this analysis focuses on the flow of a micropolar hybrid nanofluid over a vertical permeable plate. The study considers free convection of an electrically conducting fluid, incorporating metal and oxide components with a water-based hybrid nanofluid. Further, the conjunction of dissipative and radiating heat with generative/absorptive heat enhances the thermal properties. The use of standard transformation rules gives rise to converting the nondimensional form of concerned PDEs to ODEs. Moreover to get rid of the solution, for the nondimensional set of equations, a shooting-based numerical technique like Runge–Kutta (RK)-fourth-order is adopted for the standard values of several components within their range. The effectiveness of these parameters is studied and displayed through graphs. The computed result of the rate coefficients at the surface is depicted in tabular form. The comparative analysis with earlier work studied by considering the base liquid shows a good correlation in particular cases. However, the important outcomes are, the magnetized nano as well as hybrid nanoparticles produces a thicker momentum boundary layer thickness whereas it enhances the fluid temperature.
{"title":"Control of radiating heat on the heat transfer of polar hybrid nanofluid flow through a vertical permeable plate","authors":"Priya Mathur, S. R. Mishra","doi":"10.1142/s0217984924500969","DOIUrl":"https://doi.org/10.1142/s0217984924500969","url":null,"abstract":"The recent applications in industrial products and engineering need high thermal efficiency for the betterment of the shape of the products, the concept of hybrid nanofluid is significant in comparison to nanofluid and pure fluid. Therefore, this analysis focuses on the flow of a micropolar hybrid nanofluid over a vertical permeable plate. The study considers free convection of an electrically conducting fluid, incorporating metal and oxide components with a water-based hybrid nanofluid. Further, the conjunction of dissipative and radiating heat with generative/absorptive heat enhances the thermal properties. The use of standard transformation rules gives rise to converting the nondimensional form of concerned PDEs to ODEs. Moreover to get rid of the solution, for the nondimensional set of equations, a shooting-based numerical technique like Runge–Kutta (RK)-fourth-order is adopted for the standard values of several components within their range. The effectiveness of these parameters is studied and displayed through graphs. The computed result of the rate coefficients at the surface is depicted in tabular form. The comparative analysis with earlier work studied by considering the base liquid shows a good correlation in particular cases. However, the important outcomes are, the magnetized nano as well as hybrid nanoparticles produces a thicker momentum boundary layer thickness whereas it enhances the fluid temperature.","PeriodicalId":18570,"journal":{"name":"Modern Physics Letters B","volume":"27 22","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135873444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-02DOI: 10.1142/s0217984923410191
Muhammad Arslan Khan, Muhammad Atif, Sohail Ahmad, Fuad A. Awwad, Emad A. A. Ismail
This document introduces a novel concept involving an Omni-Directional Guided Vane (ODGV) encompassing a vertical axis wind turbine (VAWT) with the goal of improving its overall performance. Extensive three-dimensional computational analysis of the airfoils used in this novel ODGV structure is conducted to investigate the impact of various geometric parameters. Diverse geometric configurations of the ODGV are explored to analyze wind flow behavior across the turbine utilizing a well-validated computational fluid dynamics (CFD) model. The numerical investigations employ the Reynolds Averaged Navier–Stokes (RANS) modeling approach with the k-epsilon turbulence model. The steady state governing equations are solved using the validated CFD solver STAR CCM+. The study considers three distinct inlet velocities: 3, 6, and 9[Formula: see text]m/s, with the aim of improving flow behavior and velocity through the ODGV. Four different modifications of the ODGV are examined, and the accuracy of the CFD model is affirmed through comparison with NACA airfoil data. Integration of the ODGV results in an enhanced self-starting behavior of the VAWT, leading to a reduction in the cut-in speed. Validation results demonstrate a strong agreement with the data obtained from CFD simulations. These results suggest that most shape ratios, except for 0.3 and 0.4 at Tip Speed Ratio (TSR) of 1.3 and 3, contribute to enhancing power and torque coefficients. Furthermore, the findings indicate that with a Sharpe ratio of 0.56, both torque and power coefficients could be improved by up to 48% and 58%, respectively.
{"title":"Numerical analysis of airfoils used in an omni-directional-guide vane structure of vertical axis wind turbine for high-rise buildings","authors":"Muhammad Arslan Khan, Muhammad Atif, Sohail Ahmad, Fuad A. Awwad, Emad A. A. Ismail","doi":"10.1142/s0217984923410191","DOIUrl":"https://doi.org/10.1142/s0217984923410191","url":null,"abstract":"This document introduces a novel concept involving an Omni-Directional Guided Vane (ODGV) encompassing a vertical axis wind turbine (VAWT) with the goal of improving its overall performance. Extensive three-dimensional computational analysis of the airfoils used in this novel ODGV structure is conducted to investigate the impact of various geometric parameters. Diverse geometric configurations of the ODGV are explored to analyze wind flow behavior across the turbine utilizing a well-validated computational fluid dynamics (CFD) model. The numerical investigations employ the Reynolds Averaged Navier–Stokes (RANS) modeling approach with the k-epsilon turbulence model. The steady state governing equations are solved using the validated CFD solver STAR CCM+. The study considers three distinct inlet velocities: 3, 6, and 9[Formula: see text]m/s, with the aim of improving flow behavior and velocity through the ODGV. Four different modifications of the ODGV are examined, and the accuracy of the CFD model is affirmed through comparison with NACA airfoil data. Integration of the ODGV results in an enhanced self-starting behavior of the VAWT, leading to a reduction in the cut-in speed. Validation results demonstrate a strong agreement with the data obtained from CFD simulations. These results suggest that most shape ratios, except for 0.3 and 0.4 at Tip Speed Ratio (TSR) of 1.3 and 3, contribute to enhancing power and torque coefficients. Furthermore, the findings indicate that with a Sharpe ratio of 0.56, both torque and power coefficients could be improved by up to 48% and 58%, respectively.","PeriodicalId":18570,"journal":{"name":"Modern Physics Letters B","volume":"61 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135975460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-31DOI: 10.1142/s0217984924500830
Chu A. Kwang-Hua, Zhiqin Qiao, Zhi-Hui Li, Yingchao Xiao
Using similarity methods with general physical assumptions and sufficient mathematical relations, researchers can obtain approximate solutions ready for experimental confirmation. Singh et al. claimed to have analyzed the second-kind self-similar motion of converging cylindrical shock waves in magnetogasdynamics. However, we found the dominated equation (11) and relevant equations of Singh et al. [Chin. Phys. Lett. 28(9) (2011) 094701] as well as the dominated equation (12) and relevant equations of Singh et al. [AIAA J. 48(11) (2010) 2523] being not correct. We show the correct mathematical derivations in details. It seems to us corresponding equations as well as illustrations by Singh et al. are of doubt due to above-mentioned issues. Our results imply the similarity exponent [Formula: see text] obtained by Singh et al. will be close to that for the converging spherical shock waves.
利用具有一般物理假设和充分数学关系的相似方法，研究人员可以得到可供实验验证的近似解。Singh等人声称在磁气动力学中分析了会聚圆柱激波的第二类自相似运动。然而，我们找到了Singh等人的支配方程(11)和相关方程。理论物理。Lett. 28(9)(2011) 094701]以及Singh等人的主导方程(12)和相关方程[AIAA J. 48(11)(2010) 2523]不正确。我们详细地给出了正确的数学推导。在我们看来，由于上述问题，相应的方程以及Singh等人的插图似乎存在疑问。我们的结果表明Singh等人得到的相似指数[公式:见文本]将接近于收敛球形激波的相似指数。
{"title":"Note on Landau–Stanyukovich rule and the similarity parameter of converging shock waves","authors":"Chu A. Kwang-Hua, Zhiqin Qiao, Zhi-Hui Li, Yingchao Xiao","doi":"10.1142/s0217984924500830","DOIUrl":"https://doi.org/10.1142/s0217984924500830","url":null,"abstract":"Using similarity methods with general physical assumptions and sufficient mathematical relations, researchers can obtain approximate solutions ready for experimental confirmation. Singh et al. claimed to have analyzed the second-kind self-similar motion of converging cylindrical shock waves in magnetogasdynamics. However, we found the dominated equation (11) and relevant equations of Singh et al. [Chin. Phys. Lett. 28(9) (2011) 094701] as well as the dominated equation (12) and relevant equations of Singh et al. [AIAA J. 48(11) (2010) 2523] being not correct. We show the correct mathematical derivations in details. It seems to us corresponding equations as well as illustrations by Singh et al. are of doubt due to above-mentioned issues. Our results imply the similarity exponent [Formula: see text] obtained by Singh et al. will be close to that for the converging spherical shock waves.","PeriodicalId":18570,"journal":{"name":"Modern Physics Letters B","volume":"25 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135814177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The phenomenon of natural convection in rectangular cavities of different aspect ratios is considered. The water is considered a base fluid associated with copper nanoparticles. The flow is induced only due to buoyancy force that arises by heating the right side of the cavity. The left side is set cold while the other walls are assumed to be at zero flux temperature. The governing equations of the present communication are simulated by the finite difference method. This study explores the impacts of Rayleigh number (Ra), Prandtl number (Pr), nanoparticles volume fraction ([Formula: see text]), and aspect ratio (A). Different combinations of these parameters are investigated. Compared to other parameters, Rayleigh number (10[Formula: see text]), aspect ratio ([Formula: see text]), and volume fraction of nanoparticles ([Formula: see text]), A is found more effective on the flow field and isotherms. Regression curves are determined for the mean Nusselt number (Nu avg ) as a function of Ra for different cases. It is found that Nu avg more precisely fits the exponential function. Also, it is found that Nu avg decreases as the values of A increase. But, [Formula: see text], shows the opposite behavior. It is noticed that when the A of the cavity grows, so does the mean heat transfer Nu. With rising Ra, the local heat transfer Nu L decreases and the heat transfer rises. In the case of the square cavity, the regression coefficient for Nu avg is found to be 0.3673 and 0.2514 for an exponential function.
{"title":"A meticulous study of aspect ratio impacts on flow and heat of nanofluid in a cavity: Finite difference-based computations","authors":"Ijaz Ahmad, Shafee Ahmad, Afraz Hussain Majeed, Tarik Lamoudan, Imran Siddique","doi":"10.1142/s0217984924500933","DOIUrl":"https://doi.org/10.1142/s0217984924500933","url":null,"abstract":"The phenomenon of natural convection in rectangular cavities of different aspect ratios is considered. The water is considered a base fluid associated with copper nanoparticles. The flow is induced only due to buoyancy force that arises by heating the right side of the cavity. The left side is set cold while the other walls are assumed to be at zero flux temperature. The governing equations of the present communication are simulated by the finite difference method. This study explores the impacts of Rayleigh number (Ra), Prandtl number (Pr), nanoparticles volume fraction ([Formula: see text]), and aspect ratio (A). Different combinations of these parameters are investigated. Compared to other parameters, Rayleigh number (10[Formula: see text]), aspect ratio ([Formula: see text]), and volume fraction of nanoparticles ([Formula: see text]), A is found more effective on the flow field and isotherms. Regression curves are determined for the mean Nusselt number (Nu avg ) as a function of Ra for different cases. It is found that Nu avg more precisely fits the exponential function. Also, it is found that Nu avg decreases as the values of A increase. But, [Formula: see text], shows the opposite behavior. It is noticed that when the A of the cavity grows, so does the mean heat transfer Nu. With rising Ra, the local heat transfer Nu L decreases and the heat transfer rises. In the case of the square cavity, the regression coefficient for Nu avg is found to be 0.3673 and 0.2514 for an exponential function.","PeriodicalId":18570,"journal":{"name":"Modern Physics Letters B","volume":"55 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135813676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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