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A conservative wavelet upwind scheme for compressible flows
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作者 Bing Yang Xiaojing Liu +1 位作者 Youhe Zhou Jizeng Wang 《Acta Mechanica Sinica》 2025年第7期149-167,共19页
In this paper,we develop a fourth-order conservative wavelet-based shock-capturing scheme.The scheme is constructed by combining a wavelet collocation upwind method with the monotonic tangent of hyperbola for interfac... In this paper,we develop a fourth-order conservative wavelet-based shock-capturing scheme.The scheme is constructed by combining a wavelet collocation upwind method with the monotonic tangent of hyperbola for interface capturing(THINC)technique.We employ boundary variation diminishing(BVD)reconstruction to enhance the scheme’s effectiveness in handling shocks.First,we prove that wavelet collocation upwind schemes based on interpolating wavelets can be reformulated into a conservative form within the framework of wavelet theory,forming the foundation of the proposed scheme.The new fourthorder accurate scheme possesses significantly better spectral resolution than the fifth-and even seventh-order WENO-Z(weighted essentially non-oscillatory)schemes over the entire wave-number range.Moreover,the inherent low-pass filtering property of the wavelet bases allows them to filter high-frequency numerical oscillations,endowing the wavelet upwind scheme with robustness and accuracy in solving problems under extreme conditions.Notably,due to the wavelet multiresolution approximation,the proposed scheme possesses a distinctive shape-preserving property absent in the WENO-Z schemes and the fifth-order schemes with BVD reconstruction based on polynomials.Furthermore,compared to the fifth-order scheme with BVD reconstruction based on polynomials—which is significantly superior to the WENO schemes—the proposed scheme further enhances the ability to capture discontinuities. 展开更多
关键词 Conservative wavelet upwind scheme Boundary variation diminishing THINC scheme HIGH-RESOLUTION Compressible flows
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A MIXED FINITE ELEMENT AND UPWIND MIXED FINITE ELEMENT MULTI-STEP METHOD FOR THE THREE-DIMENSIONAL POSITIVE SEMI-DEFINITE DARCY-FORCHHEIMER MISCIBLE DISPLACEMENT PROBLEM
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作者 Yirang YUAN Changfeng LI +1 位作者 Huailing SONG Tongjun SUN 《Acta Mathematica Scientia》 2025年第2期715-736,共22页
In this paper,a composite numerical scheme is proposed to solve the threedimensional Darcy-Forchheimer miscible displacement problem with positive semi-definite assumptions.A mixed finite element is used for the fow e... In this paper,a composite numerical scheme is proposed to solve the threedimensional Darcy-Forchheimer miscible displacement problem with positive semi-definite assumptions.A mixed finite element is used for the fow equation.The velocity and pressure are computed simultaneously.The accuracy of velocity is improved one order.The concentration equation is solved by using mixed finite element,multi-step difference and upwind approximation.A multi-step method is used to approximate time derivative for improving the accuracy.The upwind approximation and an expanded mixed finite element are adopted to solve the convection and diffusion,respectively.The composite method could compute the diffusion flux and its gradient.It possibly becomes an eficient tool for solving convection-dominated diffusion problems.Firstly,the conservation of mass holds.Secondly,the multi-step method has high accuracy.Thirdly,the upwind approximation could avoid numerical dispersion.Using numerical analysis of a priori estimates and special techniques of differential equations,we give an error estimates for a positive definite problem.Numerical experiments illustrate its computational efficiency and feasibility of application. 展开更多
关键词 Darcy-Forchheimer fow three-dimensional positive semi-definite problem upwind mixed finite element multi-step method conservation of mass convergence analysis
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基于Upwind差分格式的电缆故障测距仿真系统 被引量:3
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作者 黄俊彦 刘永强 +1 位作者 马士超 谢萍 《光纤与电缆及其应用技术》 2010年第3期22-26,共5页
波反射法是目前电力电缆故障测距的主要方法,而波反射法采集到的故障波形复杂多变,分析较为困难。因此利用电缆的传输线模型,在分析偏微分方程数值解理论的基础上,提出了基于Upwind差分格式来进行传输线时域分析,并由此建立电缆故障测... 波反射法是目前电力电缆故障测距的主要方法,而波反射法采集到的故障波形复杂多变,分析较为困难。因此利用电缆的传输线模型,在分析偏微分方程数值解理论的基础上,提出了基于Upwind差分格式来进行传输线时域分析,并由此建立电缆故障测距仿真系统。检修人员通过仿真软件,学习分析电缆故障测距中可能出现的各种波形,可以提高工程实际中故障点的判断能力。仿真结果表明,仿真波形与工程实际中测试到的故障波形基本一致,能够很好地用于对电缆故障检修人员进行培训。 展开更多
关键词 波反射法 故障测距 upwind 传输线时域分析
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APPLICATIONS OF HIGHER-ORDER UPWIND SCHEME FOR PROJECTILES IN TRANSONIC FLOW
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作者 鞠玉涛 郑亚 武晓松 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共3页
针对弹丸跨音速粘性绕流流场进行了数值仿真研究,并与实验进行了对比。数值仿真的控制方程为雷诺平均的Navier-Stokes方程,湍流模型采用Baldwin-Lomax模型,应用了四阶的MUSCL TVD格式。结果表明,该方法可以取得高清晰度的流场结构。
关键词 TVD格式 NAVIER-STOKES方程 弹丸流动 APPLICATIONS OF HIGHER-ORDER upwind SCHEME FOR
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PARALLELIZED UPWIND FLUX SPLITTING SCHEME FOR SUPERSONIC REACTING FLOWS ON UNSTRUCTURED HYBRID MESHES
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作者 王江峰 伍贻兆 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第3期218-224,共7页
A parallelized upwind flux splitting scheme for supersonic reacting flows on hybrid meshes is presented. The complexity of super/hyper-sonic combustion flows makes it necessary to establish solvers with higher resolut... A parallelized upwind flux splitting scheme for supersonic reacting flows on hybrid meshes is presented. The complexity of super/hyper-sonic combustion flows makes it necessary to establish solvers with higher resolution and efficiency for multi-component Euler/N-S equations. Hence, a spatial second-order van Leer type flux vector splitting scheme is established by introducing auxiliary points in interpolation, and a domain decomposition method used on unstructured hybrid meshes for obtaining high calculating efficiency. The numerical scheme with five-stage Runge-Kutta time step method is implemented to the simulation of combustion flows, including the supersonic hydrogen/air combustion and the normal injection of hydrogen into reacting flows. Satisfying results are obtained compared with limited references. 展开更多
关键词 supersonic combustion chemical reaction upwind scheme PARALLELIZATION
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NUMERICAL METHOD OF MIXED FINITE VOLUME-MODIFIED UPWIND FRACTIONAL STEP DIFFERENCE FOR THREE-DIMENSIONAL SEMICONDUCTOR DEVICE TRANSIENT BEHAVIOR PROBLEMS 被引量:5
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作者 袁益让 杨青 +1 位作者 李长峰 孙同军 《Acta Mathematica Scientia》 SCIE CSCD 2017年第1期259-279,共21页
Transient behavior of three-dimensional semiconductor device with heat conduc- tion is described by a coupled mathematical system of four quasi-linear partial differential equations with initial-boundary value conditi... Transient behavior of three-dimensional semiconductor device with heat conduc- tion is described by a coupled mathematical system of four quasi-linear partial differential equations with initial-boundary value conditions. The electric potential is defined by an ellip- tic equation and it appears in the following three equations via the electric field intensity. The electron concentration and the hole concentration are determined by convection-dominated diffusion equations and the temperature is interpreted by a heat conduction equation. A mixed finite volume element approximation, keeping physical conservation law, is used to get numerical values of the electric potential and the accuracy is improved one order. Two con- centrations and the heat conduction are computed by a fractional step method combined with second-order upwind differences. This method can overcome numerical oscillation, dispersion and decreases computational complexity. Then a three-dimensional problem is solved by computing three successive one-dimensional problems where the method of speedup is used and the computational work is greatly shortened. An optimal second-order error estimate in L2 norm is derived by using prior estimate theory and other special techniques of partial differential equations. This type of mass-conservative parallel method is important and is most valuable in numerical analysis and application of semiconductor device. 展开更多
关键词 three dimensional transient behavior of heat conduction problem mixed finitevolume element modified upwind fractional step difference second-order error
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UPWIND LOCAL DIFFERENTIAL QUADRATURE METHOD FOR SOLVING COUPLED VISCOUS FLOW AND HEAT TRANSFER EQUATIONS 被引量:1
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作者 A.S.J.Al-Saif 朱正佑 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第10期1130-1138,共9页
The differential quadrature method (DQM) has been applied successfully to solve numerically many problems in the fluid mechanics. But it is only limited to the flow problems in regular regions. At the same time, here ... The differential quadrature method (DQM) has been applied successfully to solve numerically many problems in the fluid mechanics. But it is only limited to the flow problems in regular regions. At the same time, here is no upwind mechanism to deal with the convective property of the fluid flow in traditional DQ method. A local differential quadrature method owning upwind mechanism (ULDQM) was given to solve the coupled problem of incompressible viscous flow and heat transfer in an irregular region. For the problem of flow past a contraction channel whose boundary does not parallel to coordinate direction, the satisfactory numerical solutions were obtained by using ULDQM with a few grid points. The numerical results show that the ULDQM possesses advantages including well convergence, less computational workload and storage as compared with the low-order finite difference method. 展开更多
关键词 upwind locall DQM Navier-Stokes equation heat equation
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Streamline upwind finite element method using 6-node triangular element with adaptive remeshing technique for convective-diffusion problems 被引量:1
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作者 Niphon Wansophark Pramote Dechaumphai 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第11期1439-1450,共12页
A streamline upwind finite element method using 6-node triangular element is presented. The method is applied to the convection term of the governing transport equation directly along local streamlines. Several convec... A streamline upwind finite element method using 6-node triangular element is presented. The method is applied to the convection term of the governing transport equation directly along local streamlines. Several convective-diffusion examples are used to evaluate efficiency of the method. Results show that the method is monotonic and does not produce any oscillation. In addition, an adaptive meshing technique is combined with the method to further increase accuracy of the solution, and at the same time, to minimize computational time and computer memory requirement. 展开更多
关键词 streamline upwind finite element method convective-diffusion problem
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Streamline upwind finite element method for conjugate heat transfer problems 被引量:3
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作者 Niphon Wansophark Atipong Malatip Pramote Dechaumphai 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第5期436-443,共8页
This paper presents a combined finite element method for solving conjugate heat transfer problems where heat conduction in a solid is coupled with heat convection in viscous fluid flow. The streamline upwind finite el... This paper presents a combined finite element method for solving conjugate heat transfer problems where heat conduction in a solid is coupled with heat convection in viscous fluid flow. The streamline upwind finite element method is used for the analysis of thermal viscous flow in the fluid region, whereas the analysis of heat conduction in solid region is performed by the Galerkin method. The method uses the three-node triangular element with equal-order interpolation functions for all the variables of the velocity components, the pressure and the temperature. The main advantage of the proposed method is to consistently couple heat transfer along the fluid-solid interface. Three test cases, i.e. conjugate Couette flow problem in parallel plate channel, counter-flow in heat exchanger, and conjugate natural convection in a square cavity with a conducting wall, are selected to evaluate the efficiency of the present method. 展开更多
关键词 Streamline upwind.Conjugate heat transfer.Finite element method
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Third-Order Upwind Schemes for Convection Equations
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作者 丁丽娟 《Journal of Beijing Institute of Technology》 EI CAS 1999年第1期31-36,共6页
Aim To construct a third order upwind scheme for convection equation. Methods Upwind Lagrange interpolation was used. Results and Conclusion The schemes L p stability for p∈ is proved. Numerical exam... Aim To construct a third order upwind scheme for convection equation. Methods Upwind Lagrange interpolation was used. Results and Conclusion The schemes L p stability for p∈ is proved. Numerical examples show that performance of the third order upwind scheme is better than that of most second order schemes. 展开更多
关键词 upwind scheme convection equation L p stability
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Numerical Analysis of Upwind Difference Schemes for Two-Dimensional First-Order Hyperbolic Equations with Variable Coefficients 被引量:1
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作者 Yanmeng Sun Qing Yang 《Engineering(科研)》 2021年第6期306-329,共24页
In this paper, we consider the initial-boundary value problem of two-dimensional first-order linear hyperbolic equation with variable coefficients. By using the upwind difference method to discretize the spatial deriv... In this paper, we consider the initial-boundary value problem of two-dimensional first-order linear hyperbolic equation with variable coefficients. By using the upwind difference method to discretize the spatial derivative term and the forward and backward Euler method to discretize the time derivative term, the explicit and implicit upwind difference schemes are obtained respectively. It is proved that the explicit upwind scheme is conditionally stable and the implicit upwind scheme is unconditionally stable. Then the convergence of the schemes is derived. Numerical examples verify the results of theoretical analysis. 展开更多
关键词 Two-Dimensional First-Order Hyperbolic Equation Variable Coefficients upwind Difference Schemes Fourier Method Stability and Error Estimation
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The Error Estimates of Direct Discontinuous Galerkin Methods Based on Upwind-Baised Fluxes 被引量:1
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作者 Hui Bi Yixin Chen 《Journal of Applied Mathematics and Physics》 2020年第12期2964-2970,共7页
<div style="text-align:justify;"> In this paper, we study the error estimates for direct discontinuous Galerkin methods based on the upwind-biased fluxes. We use a newly global projection to obtain the... <div style="text-align:justify;"> In this paper, we study the error estimates for direct discontinuous Galerkin methods based on the upwind-biased fluxes. We use a newly global projection to obtain the optimal error estimates. The numerical experiments imply that <em>L</em><sup>2 </sup>norms error estimates can reach to order <em>k</em> + 1 by using time discretization methods. </div> 展开更多
关键词 Direct Discontinuous Galerkin Methods Global Projection Error Estimates The upwind-Biased Fluxes
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UPWIND SPLITTING SCHEME FOR CONVECTION-DIFFUSION EQUATIONS
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作者 梁栋 芮洪兴 程爱杰 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第1期45-54,共10页
WT5,5”BX] A new class of numerical schemes is proposed to solve convection diffusion equations by combining the upwind technique and the method of operator splitting. For every time step, the multi dimensional approx... WT5,5”BX] A new class of numerical schemes is proposed to solve convection diffusion equations by combining the upwind technique and the method of operator splitting. For every time step, the multi dimensional approximation is performed in several independent directions alternatively, while the upwind technique is applied to treat the convection term in every individual direction. This scheme possesses maximum principle. Stability and convergence are analysed by energy method.[WT5,5”HZ] 展开更多
关键词 CONVECTION diffusion EQUATIONS upwind SPLITTING scheme maximum PRINCIPLE stability and CONVERGENCE .
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THE UPWIND OPERATOR SPLITTING FINITE DIFFERENCE METHOD FOR COMPRESSIBLE TWO-PHASE DISPLACEMENT PROBLEM AND ANALYSIS
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作者 袁益让 《Acta Mathematica Scientia》 SCIE CSCD 2002年第4期489-499,共11页
For compressible two-phase displacement problem, a kind of upwind operator splitting finite difference schemes is put forward and make use of operator splitting, of calculus of variations, multiplicative commutation r... For compressible two-phase displacement problem, a kind of upwind operator splitting finite difference schemes is put forward and make use of operator splitting, of calculus of variations, multiplicative commutation rule of difference operators, decomposition of high order difference operators and prior estimates are adopted. Optimal order estimates in L 2 norm are derived to determine the error, in the approximate solution. 展开更多
关键词 two-phase displacement two-dimensional compressibility upwind operator splitting finite difference schemes convergence analysis
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THE UPWIND FINITE DIFFERENCE METHOD FOR MOVING BOUNDARY VALUE PROBLEM OF COUPLED SYSTEM
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作者 袁益让 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期857-881,共25页
Coupled system of multilayer dynamics of fluids in porous media is to describe the history of oil-gas transport and accumulation in basin evolution.It is of great value in rational evaluation of prospecting and exploi... Coupled system of multilayer dynamics of fluids in porous media is to describe the history of oil-gas transport and accumulation in basin evolution.It is of great value in rational evaluation of prospecting and exploiting oil-gas resources.The mathematical model can be described as a coupled system of nonlinear partial differential equations with moving boundary values.The upwind finite difference schemes applicable to parallel arithmetic are put forward and two-dimensional and three-dimensional schemes are used to form a complete set.Some techniques,such as change of variables,calculus of variations, multiplicative commutation rule of difference operators,decomposition of high order difference operators and prior estimates,are adopted.The estimates in l~2 norm are derived to determine the error in the approximate solution.This method was already applied to the numerical simulation of migration-accumulation of oil resources. 展开更多
关键词 multilayer coupled system moving boundary values upwind finite difference method CONVERGENCE numerical simulation of energy sources
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AN IMPLICIT-EXPLICIT UPWIND ALGORITHM FOR THE PARABOLIZED NAVIER-STOKES EQUATIONS
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作者 刘铁刚 王汝权 宋松和 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1994年第2期129-135,共7页
In this paper, a second-order implicit-explicit upwind algorithm has been developed for three-dimensional Parabolized Navier-Stokes(PNS) equations. The agreement between the results of the new upwind algorithm and tho... In this paper, a second-order implicit-explicit upwind algorithm has been developed for three-dimensional Parabolized Navier-Stokes(PNS) equations. The agreement between the results of the new upwind algorithm and those of the im- plicit upwind algorithm and its ability in marching a long distance along the stream- wise direction have been shown for the supersonic viscous flow past a sphere-cone body. The CPU time is greatly reduced. 展开更多
关键词 Parabolized Navier-Stokes (PNS) equations supersonic viscous flow upwind(TVD) algoritm space marching
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Upwind finite difference method for miscible oil and water displacement problem with moving boundary values
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作者 袁益让 李长峰 +1 位作者 杨成顺 韩玉笈 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第11期1365-1378,共14页
The research of the miscible oil and water displacement problem with moving boundary values is of great value to the history of oil-gas transport and accumulation in the basin evolution as well as to the rational eval... The research of the miscible oil and water displacement problem with moving boundary values is of great value to the history of oil-gas transport and accumulation in the basin evolution as well as to the rational evaluation in prospecting and exploiting oil-gas resources. The mathematical model can be described as a coupled system of nonlinear partial differential equations with moving boundary values. For the twodimensional bounded region, the upwind finite difference schemes are proposed. Some techniques, such as the calculus of variations, the change of variables, and the theory of a priori estimates, are used. The optimal orderl2-norm estimates are derived for the errors in the approximate solutions. The research is important both theoretically and practically for the model analysis in the field, the model numerical method, and the software development. 展开更多
关键词 compressible displacement moving boundary upwind finite difference frac-tional steps l2 error estimate
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Modeling Convection Diffusion with Exponential Upwinding
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作者 Humberto C. Godinez Valipuram S. Manoranjan 《Applied Mathematics》 2013年第8期80-88,共9页
This paper shows the usefulness of the exponential upwinding technique in convection diffusion computations. In particular, it is demonstrated that, even when convection is dominant, if exponential upwinding is employ... This paper shows the usefulness of the exponential upwinding technique in convection diffusion computations. In particular, it is demonstrated that, even when convection is dominant, if exponential upwinding is employed in conjunction with either the Jacobi or the Gauss-Seidel iteration process, one can obtain computed solutions that are accurate and free of unphysical 展开更多
关键词 CONVECTION Dominated Diffusion EXPONENTIAL upwindING ITERATION Matrix CONVERGENCE Spectral RADIUS
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Upwind Finite-Volume Solution of Stochastic Burgers’ Equation
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作者 Mohamed A. El-Beltagy Mohamed I. Wafa Osama H. Galal 《Applied Mathematics》 2012年第11期1818-1825,共8页
In this paper, a stochastic finite-volume solver based on polynomial chaos expansion is developed. The upwind scheme is used to avoid the numerical instabilities. The Burgers’ equation subjected to deterministic boun... In this paper, a stochastic finite-volume solver based on polynomial chaos expansion is developed. The upwind scheme is used to avoid the numerical instabilities. The Burgers’ equation subjected to deterministic boundary conditions and random viscosity is solved. The solution uncertainty is quantified for different values of viscosity. Monte-Carlo simulations are used to validate and compare the developed solver. The mean, standard deviation and the probability distribution function (p.d.f) of the stochastic Burgers’ solution is quantified and the effect of some parameters is investigated. The large sparse linear system resulting from the stochastic solver is solved in parallel to enhance the performance. Also, Monte-Carlo simulations are done in parallel and the execution times are compared in both cases. 展开更多
关键词 POLYNOMIAL Chaos Expansion Stochastic Burgers’ Equation upwind FINITE-VOLUME Technique
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Central Upwind Scheme for Solving Multivariate Cell Population Balance Models
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作者 Shahzadi Mubeen ur Rehman Nadia Kiran Shamsul Qamar 《Applied Mathematics》 2014年第8期1187-1201,共15页
Microbial cultures are comprised of heterogeneous cells that differ according to their size and intracellular concentrations of DNA, proteins and other constituents. Because of the included level of details, multi-var... Microbial cultures are comprised of heterogeneous cells that differ according to their size and intracellular concentrations of DNA, proteins and other constituents. Because of the included level of details, multi-variable cell population balance models (PBMs) offer the most general way to describe the complicated phenomena associated with cell growth, substrate consumption and product formation. For that reason, solving and understanding of such models are essential to predict and control cell growth in the processes of biotechnological interest. Such models typically consist of a partial integro-differential equation for describing cell growth and an ordinary integro-differential equation for representing substrate consumption. However, the involved mathematical complexities make their numerical solutions challenging for the given numerical scheme. In this article, the central upwind scheme is applied to solve the single-variate and bivariate cell population balance models considering equal and unequal partitioning of cellular materials. The validity of the developed algorithms is verified through several case studies. It was found that the suggested scheme is more reliable and effective. 展开更多
关键词 CELL Population BALANCE CELL Growth Substrate CONSUMPTION CENTRAL upwind Scheme Equal and Unequal Partitioning of Cells
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