Pramana最新文献

筛选
英文 中文
Stagnation point of the triple nanoparticle nanofluid flow through the spinning sphere with radiation absorption 带有辐射吸收的三重纳米粒子纳米流体流经旋转球的停滞点
IF 1.9 4区 物理与天体物理
Pramana Pub Date : 2024-07-11 DOI: 10.1007/s12043-024-02768-5
Kotha Gangadhar, Naga Chandrika G, Saeed Dinarvand
{"title":"Stagnation point of the triple nanoparticle nanofluid flow through the spinning sphere with radiation absorption","authors":"Kotha Gangadhar,&nbsp;Naga Chandrika G,&nbsp;Saeed Dinarvand","doi":"10.1007/s12043-024-02768-5","DOIUrl":"10.1007/s12043-024-02768-5","url":null,"abstract":"<div><p>Heat absorption and thermal radiation have significant roles in engineering and research. These two principles have applications in thermal transportation, gas turbines, nuclear power plants, electrical fuel, aerospace engineering, projectiles and renewable energy. The present work analyses the stagnation point ternary nanofluid motion over a circulating sphere in the presence of a magnetic field and radiation absorption. The nonlinear controlling equations are replaced by ordinary differential equations by applying a suitable comparison factor. The bvp4c process was used to establish numerical outcomes of the partial differential equations. This mathematical numerical findings are presented graphically. The results of ternary nanoparticles (Cu–Ag–CuO/water), hybrid nanoparticles (Cu–Ag/water) and copper (Cu) nanoparticles have also been compared, and this comparison suggests that ternary nanoparticles (Cu–Ag–CuO/water) are more effective at attenuating hemodynamic factors (such as wall shear stress and heat transfer) than hybrid and copper (Cu) nanoparticles. Comparison with previous literature results is also done and the results are found to be in very good agreement with those published earlier.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"98 3","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141588508","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}
引用次数: 0
Resonance behaviour for a bistable system driven by random-phase square-wave signal-modulated noise and multiplicative noise 由随机相位方波信号调制噪声和乘法噪声驱动的双稳态系统的共振行为
IF 1.9 4区 物理与天体物理
Pramana Pub Date : 2024-07-11 DOI: 10.1007/s12043-024-02807-1
Feng Guo, Cheng-Yin Zhu, Qiang-Ming Cai, Jian-Wei Wang
{"title":"Resonance behaviour for a bistable system driven by random-phase square-wave signal-modulated noise and multiplicative noise","authors":"Feng Guo,&nbsp;Cheng-Yin Zhu,&nbsp;Qiang-Ming Cai,&nbsp;Jian-Wei Wang","doi":"10.1007/s12043-024-02807-1","DOIUrl":"10.1007/s12043-024-02807-1","url":null,"abstract":"<div><p>The stochastic resonance (SR) phenomenon for a bistable system subject to signal-modulated noise and to multiplicative and additive noise is investigated. The signal is modelled as a random-phase asymmetric square-wave one. Based on adiabatic approximation condition and two-state theory, the system output signal-to-noise ratio (SNR) is deduced. It is found that double SR phenomenon occurs when the SNR varies with the asymmetry of the square-wave signal. One resonance peak appears when the SNR changes with the amplitude of the square-wave signal. Traditional SR can be observed on the curves of the SNRs vs. the strength of the signal-modulated noise and vs. the intensities of the multiplicative and additive noise. The non-monotonous dependence of the SNR on the system parameter is discussed.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"98 3","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141588630","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}
引用次数: 0
Enhancing heat transfer on the free convection of conducting hybrid nanofluid through stretching/shrinking surface 通过拉伸/收缩表面增强导电混合纳米流体的自由对流传热
IF 1.9 4区 物理与天体物理
Pramana Pub Date : 2024-07-11 DOI: 10.1007/s12043-024-02762-x
Ram Prakash Sharma, P K Pattnaik, S R Mishra, Seema Tinker, Subba Rao Allipudi
{"title":"Enhancing heat transfer on the free convection of conducting hybrid nanofluid through stretching/shrinking surface","authors":"Ram Prakash Sharma,&nbsp;P K Pattnaik,&nbsp;S R Mishra,&nbsp;Seema Tinker,&nbsp;Subba Rao Allipudi","doi":"10.1007/s12043-024-02762-x","DOIUrl":"10.1007/s12043-024-02762-x","url":null,"abstract":"<div><p>A study is carried out for the flow of a steady two-dimensional hybrid nanofluid through an exponentially expanding/shrinking surface under the influence of a magnetic field. Further, the impact of thermal buoyancy is also incorporated into the momentum equation. The model is developed using the rheological properties of hybrid nanofluid, such as viscosity, conductivity, specific heat, etc. that develop the physical significance of nanofluid. The principal equations for the motion are re-constructed to their dimensionless form by implementing similarity transformation and these are handled numerically using Runge–Kutta fourth-order. The crux of the problem is that the dual solution is obtained for the particular flow parameters. Further, the simulation is carried out by setting the characterising parameters, and their characteristics are explained briefly. The important outcomes of the study are: for the enhanced volume concentration the velocity profile enhances significantly in the case of the first solution and the impact is opposite in the case of the second solution.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"98 3","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141586880","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}
引用次数: 0
Numerical investigation of tunable and switchable refractive index-based mid-infrared metamaterial absorber 基于折射率的可调谐和可切换中红外超材料吸收器的数值研究
IF 1.9 4区 物理与天体物理
Pramana Pub Date : 2024-07-11 DOI: 10.1007/s12043-024-02789-0
Nikita Choudhary, Anjani Kumar Tiwari
{"title":"Numerical investigation of tunable and switchable refractive index-based mid-infrared metamaterial absorber","authors":"Nikita Choudhary,&nbsp;Anjani Kumar Tiwari","doi":"10.1007/s12043-024-02789-0","DOIUrl":"10.1007/s12043-024-02789-0","url":null,"abstract":"<div><p>In this paper, we numerically investigate a tunable and switchable metamaterial absorber operating in the mid-infrared region. The metamaterial structure comprises an array of metal–dielectric concentric nanodisks and a metal square patch on a substrate coated with thin dielectric and metal layers. The two dielectric regions induce two absorption bands, which can be independently tuned by changing the refractive index and geometrical parameters of the dielectric layers. In an optimised geometry, a dual-band to a single-band switchable frequency response is achieved by interchanging the refractive index of the dielectric layers. The origin of the resonant absorptions is traced to the simultaneous excitation of electric and magnetic fields in the dielectric regions. Due to architectural symmetry, the investigated structure is polarisation-insensitive and exhibits high absorption over a wide range of angles.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"98 3","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141586882","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}
引用次数: 0
Universal relations of dyonic ModMax and Taub-NUT black holes thermodynamics and central charge dyonic ModMax 和 Taub-NUT 黑洞热力学与中心电荷的普遍关系
IF 1.9 4区 物理与天体物理
Pramana Pub Date : 2024-07-08 DOI: 10.1007/s12043-024-02783-6
F Khosravani, J Sadeghi, S Noori Gashti
{"title":"Universal relations of dyonic ModMax and Taub-NUT black holes thermodynamics and central charge","authors":"F Khosravani,&nbsp;J Sadeghi,&nbsp;S Noori Gashti","doi":"10.1007/s12043-024-02783-6","DOIUrl":"10.1007/s12043-024-02783-6","url":null,"abstract":"<div><p>In this paper, we studied the thermodynamic quantities of dyonic ModMax and Taub-NUT black holes (BHs) to investigate their universal relations, viz. that product formulas are mass-independent. So, we calculated the thermodynamic parameters of these BHs in the inner and outer event horizons. We also obtained information about the left and right central charges. We showed that the central charges are not independent of the mass, i.e., they do not correspond to the conformal field theory (CFT). Also, we showed that the two sides of the central charge for the Taub-NUT BH are the same. These results play an important role in improving AdS/CFT and holography and thermodynamic studies. Finally, we compared our results with the other works in the literature.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"98 3","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141570020","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}
引用次数: 0
Correction: The optimal values of Greenwald density limit and plasma safety factor in inductive and non-inductive operation modes 更正:感应和非感应运行模式下格林沃尔德密度极限和等离子体安全系数的最佳值
IF 1.9 4区 物理与天体物理
Pramana Pub Date : 2024-07-08 DOI: 10.1007/s12043-024-02800-8
F Sharifi, S M Motevalli, F Fadaei
{"title":"Correction: The optimal values of Greenwald density limit and plasma safety factor in inductive and non-inductive operation modes","authors":"F Sharifi,&nbsp;S M Motevalli,&nbsp;F Fadaei","doi":"10.1007/s12043-024-02800-8","DOIUrl":"10.1007/s12043-024-02800-8","url":null,"abstract":"","PeriodicalId":743,"journal":{"name":"Pramana","volume":"98 3","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141666560","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}
引用次数: 0
Oblique corrections when (m_W ne m_Z cos {theta _W}) at tree level 当 $$m_W ne m_Z cos {theta _W}$ 在树级时的斜向修正
IF 1.9 4区 物理与天体物理
Pramana Pub Date : 2024-07-08 DOI: 10.1007/s12043-024-02771-w
Simonas Draukšas, Vytautas Dūdėnas, Luís Lavoura
{"title":"Oblique corrections when (m_W ne m_Z cos {theta _W}) at tree level","authors":"Simonas Draukšas,&nbsp;Vytautas Dūdėnas,&nbsp;Luís Lavoura","doi":"10.1007/s12043-024-02771-w","DOIUrl":"10.1007/s12043-024-02771-w","url":null,"abstract":"<div><p>The parametrization of the oblique corrections through <i>S</i>, <i>T</i>, and <i>U</i> – later extended by <i>V</i>, <i>W</i> and <i>X</i> – is a convenient way of comparing the predictions for various electroweak observables at the one-loop level between the Standard Model and its extensions. That parametrization assumes that the extensions under consideration have <span>({SU(2)times U(1)})</span> gauge symmetry <i>and</i> the tree-level relation <span>(m_W = m_Z cos {theta _W})</span> between the Weinberg angle and the gauge-boson masses. In models where that relation does not hold at the Lagrangian level, the parameter <i>T</i> is not ultraviolet-finite, making the parametrization inadequate. We present expressions that parametrize the difference of the various predictions of two models with <span>(m_W ne m_Z cos {theta _W})</span> in terms of oblique parameters. The parameter <i>T</i> does not play a role in those expressions. Conveniently, they may be reached from the ones that were derived for models with tree-level <span>(m_W = m_Z cos {theta _W})</span>, by performing a simple substitution for <i>T</i>. We also discuss the difficulties in using oblique parameters when comparing a model with <span>(m_W ne m_Z cos {theta _W})</span> to the Standard Model. Finally, we compute the relevant five oblique parameters <i>S</i>, <i>U</i>, <i>V</i>, <i>W</i> and <i>X</i> in the SM extended by both, hypercharge <span>(Y=0)</span> and <span>(Y=1)</span>, triplet scalars.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"98 3","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141570049","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}
引用次数: 0
Energy and charge radii of Li isotopes in a two-body configuration 双体构型锂同位素的能量和电荷半径
IF 1.9 4区 物理与天体物理
Pramana Pub Date : 2024-07-04 DOI: 10.1007/s12043-024-02779-2
Nasrin Malekinezhad, Mohammadreza Shojaei, Cristian Massimi
{"title":"Energy and charge radii of Li isotopes in a two-body configuration","authors":"Nasrin Malekinezhad,&nbsp;Mohammadreza Shojaei,&nbsp;Cristian Massimi","doi":"10.1007/s12043-024-02779-2","DOIUrl":"10.1007/s12043-024-02779-2","url":null,"abstract":"<div><p>The study of the static properties of isotopes, such as ground-state energy of the system and the energy spectra, electric quadrupole, as well as charge radii and so many others, is one of the significant areas of interest in nuclear physics. Therefore, in this field, the ground-state energy of a nucleus is an essential part of the study. In addition, understanding the nuclear force depends critically on understanding the nuclear charge radii. In this work, we considered Li isotopes in the study of two-body system configuration, and then we calculated the ground-state energy and charge radii for some of them.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"98 3","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141552358","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}
引用次数: 0
Uncertain effects of thermal radiation and magnetic field in the micropolar fluid flow through porous channel walls with hybrid nanoparticles 热辐射和磁场在微极性流体流经多孔通道壁与混合纳米颗粒中的不确定效应
IF 1.9 4区 物理与天体物理
Pramana Pub Date : 2024-07-04 DOI: 10.1007/s12043-024-02758-7
Ajay Kumar, Ramakanta Meher
{"title":"Uncertain effects of thermal radiation and magnetic field in the micropolar fluid flow through porous channel walls with hybrid nanoparticles","authors":"Ajay Kumar,&nbsp;Ramakanta Meher","doi":"10.1007/s12043-024-02758-7","DOIUrl":"10.1007/s12043-024-02758-7","url":null,"abstract":"<div><p>This work considers a micropolar hybrid nanofluid flow through a resistive porous media between channel walls to study the uncertain effects of thermal radiation and magnetic field on the velocity and thermal profiles by considering distinctly shaped nanoparticles such as copper (Cu) and hybrid nanoparticles such as copper–alumina (Cu–Al<span>(_{2})</span>O<span>(_{3}))</span>. Three different forms of the nanoparticles, spherical, cylindrical and blade are examined considering the flow’s heat radiation and magnetic field impact. \u0000Here, the volume fractions of nanoparticles are expressed with the triangular fuzzy number ranging from 0 to 2.5% to examine its uncertain effects on the velocity and thermal profiles by employing a double parameter-based homotopy approach. The homotopy analytical approach has proven its efficacy in approximating solutions to diverse nonlinear problems owing to its rapid solution convergence. The obtained results are validated with the available results in crisp cases, and a graphical with numerical illustration has been made to study the behaviour of the fuzzy velocity, microrotation, temperature and concentration profiles under the effect of distinct parameters. The findings of this study indicate that, despite micropolar effects and porosity, the heat transmission rate is improved in hybrid nanofluids and blade-shaped nanoparticles compared to cylindrical and spherical-shaped nanoparticles.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"98 3","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141552359","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}
引用次数: 0
Monte Carlo solution of the reflected systems’ criticality problems with Anlı–Güngör, Inönü and tetra-anisotropic kernels for both fission and scattered neutrons 使用安勒-贡格尔、伊诺和四各向异性核对裂变中子和散裂中子的反射系统临界问题的蒙特卡洛解法
IF 1.9 4区 物理与天体物理
Pramana Pub Date : 2024-07-04 DOI: 10.1007/s12043-024-02781-8
Bahram R Maleki
{"title":"Monte Carlo solution of the reflected systems’ criticality problems with Anlı–Güngör, Inönü and tetra-anisotropic kernels for both fission and scattered neutrons","authors":"Bahram R Maleki","doi":"10.1007/s12043-024-02781-8","DOIUrl":"10.1007/s12043-024-02781-8","url":null,"abstract":"<div><p>Different deterministic solution methods are being used to solve the criticality problem of the reflected systems with different anisotropic behaviours for both fission neutrons and neutrons undergoing scattering. In the present study, the criticality problem is simulated using the developed Monte Carlo algorithm. Different angular distributions, such as Inönü, Anlı–Güngör and tetra-anisotropic kernels are taken into account. For each anisotropic kernel, the sampling method of the direction cosine of either newborn fission neutrons or scattered neutrons is presented by extracting the required probability distribution function (PDF). The simulation starts with an initial guess and following the presented procedure, the criticality thickness of the system is estimated with a certain convergence criterion. Different variance reduction methods, such as implicit capture, Russian-roulette and splitting, are also implemented to get more precise results with a reasonable computational time cost. The validity of the presented method is verified by comparing with the results of different deterministic methods. Finally, using an exact scattering function, the three considered kernels are compared with each other. It is seen that the tetra-anisotropic kernel is the best among the considered kernels.</p></div>","PeriodicalId":743,"journal":{"name":"Pramana","volume":"98 3","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141552357","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}
引用次数: 0
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信