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Effects of Radiations and Heat Source/Sink on a Casson Fluid Flow over Nonlinear Stretching Sheet 被引量:1
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作者 Chenna Sumalatha Shankar Bandari 《World Journal of Mechanics》 2015年第12期257-265,共9页
The present study deals with the flow over a nonlinearly stretching sheet of Casson fluid with the effects of radiation and heat source/sink. The Casson fluid model is used to characterize the non-Newtonian fluid beha... The present study deals with the flow over a nonlinearly stretching sheet of Casson fluid with the effects of radiation and heat source/sink. The Casson fluid model is used to characterize the non-Newtonian fluid behaviour. With the help of justified similarity transformations the governing equations were reduced to couple nonlinear ordinary differential equations. The effective numerical technique Keller Box method is used to solve these equations. The variations in velocity, temperature profiles were presented with the various values of nonlinear stretching parameter n and Casson parameter β. The nature of Skinfriction and Local nusselt number has presented. Effects of radiation and heat source/sink on temperature profiles have been discussed. 展开更多
关键词 nonlinear STRETCHING Sheet Casson Fluid Keller BOX Method Radiation Heat source/sink
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Influence of temperature dependent heat source/sink on transient MHD free convective flow in an infinite rigid impermeable vertical cylinder with chemical reaction
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作者 Naveen Dwivedi Ashok Kumar Singh Nirmal C.Sacheti 《Propulsion and Power Research》 SCIE 2023年第4期568-583,共16页
It is increasingly apparent that the inclusion of mass transfer aspects,together with certain thermal conditions,in the momentum and energy equations governing MHD flows leads to a numbers of real life applications.Ke... It is increasingly apparent that the inclusion of mass transfer aspects,together with certain thermal conditions,in the momentum and energy equations governing MHD flows leads to a numbers of real life applications.Keeping this in view,we have attempted an exact analysis of heat and mass transfer aspects in transient hydromagnetic free convective flow of an incompressible viscous fluid through a vertical pipe under an externally applied magnetic field,assuming presence of chemical reaction and heat source/sink.The governing PDEs,which simplify to a set of 3 linear ODEs in the physical set up considered here,have been solved using Laplace transform technique,with solutions for key physical variables presented in the term of Bessel and modified Bessel functions.The influence of governing non-dimensional parameters,namely,Hartmann number,Schmidt number,source/sink parameter,Prandtl number and chemical reaction parameter,has been illustrated on the developing velocity and some concentration profiles.Some important quantities of engineering interest-surface skin friction and volumetric flow rates-have been computed too and analysed.Some notable finding worth mentioning are:(a)heat source presence causes higher fluid velocity as compared to the heat sink;(b)all important surface shear stress can be suitably controlled,among others,by chemical reaction parameter and Schmidt number.The key challenge of this study has been to obtain exact closed-form solutions of the field equations,including cumbersome Laplace inverses.This study finds innovative applications in the emerging fields such as magnetic materials processing,chemical processes,solar energy systems,etc. 展开更多
关键词 Circular cylinder Hydromagnetic transient flow Chemical reaction source/sink Free convection
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Slip flow of micropolar fluid through a permeable wedge due to the effects of chemical reaction and heat source/sink with Hall and ionslip currents:an analytic approach 被引量:1
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作者 Khilap Singh Alok Kumar Pandey Manoj Kumar 《Propulsion and Power Research》 SCIE 2020年第3期289-303,共15页
This study focuses on the combined impact of heat source/sink and chemical reaction on slip flow of micropolar fluid through a permeable wedge in the existence of Hall and ion-slip currents.The governing highly non-li... This study focuses on the combined impact of heat source/sink and chemical reaction on slip flow of micropolar fluid through a permeable wedge in the existence of Hall and ion-slip currents.The governing highly non-lincar PDEs were altered into a set of non-linear coupled ODEs by using similarity transformations.Differential transformation method(DTM)has been implemented in transformed ODEs equations.The comparison with previous literatures was performed and the data of this study was found to be in accordance with each other.The analytical solutions for skin-friction coefficients(surface drag forces),Nussclt and Sherwood numbers are depicted through graphs and tables.The study of boundary layer flow over a wedge surface plays an imperative role in the field of aerodynamics,heat exchanger,ground water pollution and geothermal system etc. 展开更多
关键词 Chemical reaction Differential transformation method(DTM) Hall current and ion slip Heat source/sink Micropolar fluid Slip velocity
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Nonlinear three-dimensional stretched flow of an Oldroyd-B fluid with convective condition, thermal radiation, and mixed convection
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作者 B. MAHANTHESH B. J. GIREESHA +2 位作者 S.A. SHEHZAD F.M. ABBASI R. S. R. GORLA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第7期969-980,共12页
The effect of non-linear convection in a laminar three-dimensional Oldroyd-B fluid flow is addressed. The heat transfer phenomenon is explored by considering the non-linear thermal radiation and heat generation/absorp... The effect of non-linear convection in a laminar three-dimensional Oldroyd-B fluid flow is addressed. The heat transfer phenomenon is explored by considering the non-linear thermal radiation and heat generation/absorption. The boundary layer as- sumptions are taken into account to govern the mathematical model of the flow analy- sis. Some suitable similarity variables are introduced to transform the partial differen- tial equations into ordinary differential systems. fifth-order techniques with the shooting method The Runge-Kutta-Fehlberg fourth- and are used to obtain the solutions of the dimensionless velocities and temperature. The effects of various physical parameters on the fluid velocities and temperature are plotted and examined. A comparison with the exact and homotopy perturbation solutions is made for the viscous fluid case, and an excellent match is noted. The numerical values of the wall shear stresses and the heat transfer rate at the wall are tabulated and investigated. The enhancement in the values of the Deborah number shows a reverse behavior on the liquid velocities. The results show that the temperature and the thermal boundary layer are reduced when the non- linear convection parameter increases. The values of the Nusselt number are higher in the non-linear radiation situation than those in the linear radiation situation. 展开更多
关键词 nonlinear thermal convection nonlinear thermal radiation Oldroyd-B fluid convective boundary condition heat source/sink
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Numerical study of a dissipative micropolar fluid flow past an inclined porous plate with heat source/sink 被引量:2
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作者 Shamshuddin MD Thirupathi Thumma 《Propulsion and Power Research》 SCIE 2019年第1期56-68,共13页
Micropolar theories present an excellent mechanism for exploring new non-Newtonian materials processing provides a stimulating area for process engineering simulation.Motivated by area for process engineering applicat... Micropolar theories present an excellent mechanism for exploring new non-Newtonian materials processing provides a stimulating area for process engineering simulation.Motivated by area for process engineering applications,the present article presents the scope offinite element method in solving a mathematical model for magnetohydrodynamic,incom-pressible,dissipative and chemically reacting micropolar fluid flow and heat and mass transferthrough a porous medium from an inclined plate with heat sourcelsink has been investigated.For this purpose,the set of governing equations have been reframed and put into adimensionless form under the assumption of low Reynolds number with appropriatedimensionless quantities that can fit into the finite element fommulation.In addition tohighlighting the operational aspects of weighted residual scheme,a detailed investigation hasbeen camied out on the associated flow stnucture,heat and mass transfer.The evolution ofmany multi-physical parameters in these variables is illustrated graphically.Finite elementcode is benchmarked with the results reported in the literature to check the validity andaccuracy under some limiting cases and excellent agreement is seen with published solutionsand results of skin friction coefficient,couple stress coefficient,Nusselt number and Sherwoodnumber for invoked parameter are tabulated which shows that increasing heat sourcelsinkparameter elevates temperature.Chemical reaction parameter reduces velocity and concentra-tion gradients.Sherwood number enhances as chemical reaction parameter increases but reverse phenomena is observed in case of inclination of angle.Furthermore,a gridindependency test has been caried out for different grid sizes which has proven this methodis adequate. 展开更多
关键词 Heat source/sink Chemical reaction Inclined porousplate Micropolar fluid Finite elementmethod(FEM)
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一维土柱试验的数学模型 被引量:2
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作者 李功胜 姚德 +3 位作者 秦惠增 杨富贵 刘洪亮 王孝勤 《山东理工大学学报(自然科学版)》 CAS 2007年第3期1-6,共6页
主要讨论了一维土柱试验模型及其反问题.考虑到溶质在土壤及地下水中迁移的非线性行为,认为通常模型中的阻滞因子应改为与溶质浓度相关的泛函,而零阶产出项应为与时间、空间及溶质浓度相关的非线性项,进而提出了一类新的描述一维土柱试... 主要讨论了一维土柱试验模型及其反问题.考虑到溶质在土壤及地下水中迁移的非线性行为,认为通常模型中的阻滞因子应改为与溶质浓度相关的泛函,而零阶产出项应为与时间、空间及溶质浓度相关的非线性项,进而提出了一类新的描述一维土柱试验的非线性数学模型.对于模型参数的识别问题,给出了两类典型的确定阻滞因子与源(汇)项系数的土柱试验反问题.最后,以淄博张店孝妇河-张冉原状土柱试验为例,应用所建立的数学模型对试验结果做了初步的阐释. 展开更多
关键词 一维土柱试验 数学模型 非线性吸附 非线性源(汇)项作用 反问题
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大气中甲烷的化学行为 被引量:4
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作者 张剑波 《环境科学研究》 EI CAS CSCD 1996年第4期10-15,共6页
甲烷作为重要的温室气体,其化学行为日益引起人们的关注。稻田排放、牲畜排放和沼泽排放等是大气甲烷重要的源;与OH自由基的反应是其主要的汇。甲烷在大气中的浓度以每年1%的速度增长,其不仅影响气候的变化,而且引起大气中OH,O_3等浓度... 甲烷作为重要的温室气体,其化学行为日益引起人们的关注。稻田排放、牲畜排放和沼泽排放等是大气甲烷重要的源;与OH自由基的反应是其主要的汇。甲烷在大气中的浓度以每年1%的速度增长,其不仅影响气候的变化,而且引起大气中OH,O_3等浓度的变化,是非常重要的化学物种。 展开更多
关键词 大气甲烷 源和汇 化学反应 排放
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关于半拉格朗日半隐式大气模式的时步问题 被引量:1
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作者 胡志晋 史月琴 《大气科学》 CSCD 北大核心 2006年第1期1-10,共10页
讨论半拉格朗日半隐式大气模式中时步的限制,展示时步过大时用一般的首尾两点平均方案计算非线性源汇项的严重误差,提出精确的源汇项计算格式并作了特例计算和比较,讨论了被模拟的大气过程和波动的特征对时步的要求,指出柯朗数NC=C.Δt/... 讨论半拉格朗日半隐式大气模式中时步的限制,展示时步过大时用一般的首尾两点平均方案计算非线性源汇项的严重误差,提出精确的源汇项计算格式并作了特例计算和比较,讨论了被模拟的大气过程和波动的特征对时步的要求,指出柯朗数NC=C.Δt/ΔX是大气模式时空步长匹配的重要参数。指出云降水和大气化学过程特征时间对相应的正定变量的计算时步的限制。 展开更多
关键词 半拉格朗日半隐式格式 非线性源汇项 时步
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具有非线性Neumann边界条件的非局部反应扩散方程解的爆破时间的下界估计
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作者 方钟波 杨蕊 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2016年第1期145-148,共4页
侧重研究具有非局部源和非线性Neumann边界条件的反应扩散方程解的爆破现象。适当的辅助函数构造法与微分不等式技巧相结合,建立了解发生爆破时爆破时间的下界。
关键词 反应扩散方程 非局部源 非线性Neumann边界 爆破时间的下界
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一类具非线性源扩散方程的熄灭和非熄灭行为 被引量:1
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作者 周森 杨作东 《数学物理学报(A辑)》 CSCD 北大核心 2016年第3期531-542,共12页
该文研究一类具非线性源的快扩散方程解的熄灭性质,借助积分模估计和上下解方法给出了解在有限时刻熄灭的充分条件,给出了解的衰退估计,并且给出了在某些参数条件下的数值模拟结果.
关键词 反应扩散方程 非线性源 熄灭 非熄灭
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南海神狐海域水合物发育区浅表层沉积物甲烷周转定量模拟
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作者 胡廷苍 张艳平 +2 位作者 胡钰 罗敏 陈多福 《海洋地质与第四纪地质》 CAS CSCD 北大核心 2020年第3期99-108,共10页
在天然气水合物发育区海底沉积物中甲烷厌氧氧化作用(AOM)是碳循环的重要组成部分。通过定量计算表层沉积物中甲烷迁移转化通量,可以更准确评估甲烷来源碳对沉积物碳库和海洋深部碳库影响。本文利用反应―运移模型对采集于南海神狐水合... 在天然气水合物发育区海底沉积物中甲烷厌氧氧化作用(AOM)是碳循环的重要组成部分。通过定量计算表层沉积物中甲烷迁移转化通量,可以更准确评估甲烷来源碳对沉积物碳库和海洋深部碳库影响。本文利用反应―运移模型对采集于南海神狐水合物发育区两个站位(SH-W19-PC、SH-W23-PC)采集的孔隙水SO42-、溶解无机碳(DIC)、Ca2+剖面进行拟合,同时对DIC碳同位素进行分析,确定近海底沉积物中的碳循环。研究显示两个站位孔隙水中SO42-和Ca2+浓度在剖面上随深度呈线性减少,DIC浓度随深度逐渐增加,其δ13CDIC值随深度逐渐降低至约-25‰,表明两个站位存在一定程度的AOM。模拟计算两个站位沉积物孔隙水溶解甲烷向上的通量分别为25.9和18.4 mmol·m^-2 a^-1,AOM作用产生的DIC分别占其总DIC量的70.7%和60%。由沉积物向海水中释放的DIC通量占DIC汇的约60%。因此,在天然气水合物发育区向海底渗漏甲烷大部分以DIC的形式进入上覆海水,这些具有极负碳同位素值的甲烷来源的DIC可能对局部深海碳库产生一定的影响。 展开更多
关键词 天然气水合物发育区 甲烷周转 反应―运移模型 DIC源汇 碳循环 南海
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A new mathematical model for soil-column experiment and parameter identification
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作者 Gongsheng LI De YAO +2 位作者 Fugui YANG Xiaoqin WANG Hongliang LIU 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期210-210,共1页
关键词 土壤实验 非线性 数学模型 地下水 浓缩 土壤化学
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源汇分布法求解非对称剖面水动力系数 被引量:3
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作者 孙晓雅 宋竞正 林焰 《大连海事大学学报》 CAS CSCD 北大核心 2006年第2期106-110,共5页
在线性切片理论中水动力系数的计算剖面按对称剖面处理,而在大幅波浪中剖面非对称的影响不容忽视,为此提出了一种基于源汇分布法的二维非对称剖面水动力系数的求解方法.首先在二维柱体周界表面上连续分布强度待定的脉动点源,然后使流场... 在线性切片理论中水动力系数的计算剖面按对称剖面处理,而在大幅波浪中剖面非对称的影响不容忽视,为此提出了一种基于源汇分布法的二维非对称剖面水动力系数的求解方法.首先在二维柱体周界表面上连续分布强度待定的脉动点源,然后使流场速度势及流函数满足除物面条件以外的全部边界条件,再通过流函数物面条件的满足来求解出待定的源强,进而由流场的辐射势计算水动力系数.经与有关文献数据和实验数据的比较,验证了该方法计算的有效性.且实算表明,剖面非对称性对某些水动力系数的影响较大. 展开更多
关键词 波浪理论 源汇分布法 非线性理论 水动力系数 非对称剖面
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溶质传输问题的一个经济差分格式
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作者 张健青 谢伟伟 +1 位作者 邹婉平 温永艳 《山东大学学报(理学版)》 CAS CSCD 北大核心 2013年第6期75-79,86,共6页
将求解线性对流扩散方程的特怔线修正交替方向有限差分格式推广到含非线性扩散项和源汇项的溶质传输问题。对流项采用沿着特征线修正的差分结合插值技术进行离散,每个时间步顺序求解两个空间方向上的一维问题,证明了格式的稳定性和收敛性。
关键词 溶质传输 非线性扩散 非线性源汇项 交替方向 特征线修正技术
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带有局部化反应源和非局部边界条件的非线性抛物型方程组解的全局存在性和爆破性
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作者 黄小萍 曾有栋 《福州大学学报(自然科学版)》 CAS CSCD 北大核心 2013年第1期6-11,共6页
使用上下解的方法解决了带局部化反应源的非线性抛物型方程组在非局部边界条件下正解的全局存在性和爆破性问题,得到一定条件下解的全局存在性和解在有限时间内爆破.
关键词 非线性抛物方程组 局部化反应源 非局部边界条件 全局存在 爆破
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