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971.
有限变形粘弹性接触的数学规划方法 总被引:2,自引:0,他引:2
研究有限变形粘弹性物体间的接触问题,同时考虑了刚体位移和摩擦等因素,导得该问题数学规划解法的标准形式,极易利用现有算法求解。 相似文献
972.
The Reynolds model is a reduced Stokes model, valid for narrow lubrication regions. In order to be able to handle locally non‐narrow regions such as pits or grooves, often displaying rapid geometrical variations, there is a need to be able to transit to the more accurate Stokes model. A fundamental problem is how to couple the two models in a numerical simulation, preferably allowing for different meshes in the different domains. In this paper, we present a weak coupling method for Reynolds and Stokes models for lubrication computations, including the possibility of cavitation in the different regions. The paper concludes with a numerical example. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
973.
This paper considers the treatment of fluid–solid interaction problems under shock wave loading, where the solid experiences large bulk Lagrangian displacements. This work addresses the issues associated with using a level set as a generalized interface for fluid–solid coupling where the fluid–solid interface is embedded in an unstructured fluid grid. We outline the formulation used for the edge‐based unstructured‐grid Euler solver. The identification of the fluid–solid interface on the unstructured fluid mesh uses a super‐sampled ??2 projection technique, which in conjunction with a Lagrangian interface position, permits fast identification of the interface and the concomitant imposition of boundary conditions. The use of a narrow‐band approach for the identification of the wetted interface is presented with the details of the construction of interface conditions. A series of two and three‐dimensional shock‐body computations are presented to demonstrate the validity of the current approach on problems with static and dynamic interfaces, including projectile/shock interaction simulations. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
974.
We present a cavitation model based on the Stokes equation and formulate adaptive finite element methods for its numerical solution. A posteriori error estimates and adaptive algorithms are derived, and numerical examples illustrating the theory are supplied, in particular with comparison to the simplified Reynolds model of lubrication. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
975.
An adaptive mixed least squares Galerkin/Petrov finite element method (FEM) is developed for stationary conduction convection problems. The mixed least squares Galerkin/Petrov FEM is consistent and stable for any combination of discrete velocity and pressure spaces without requiring the Babuska-Brezzi stability condition. Using the general theory of Verfürth, the posteriori error estimates of the residual type are derived. Finally, numerical tests are presented to illustrate the effectiveness of the method. 相似文献
976.
This paper proposes a new collocation method for initial value problems of second order ODEs based on the Laguerre-Gauss interpolation. It provides the global numerical solutions and possesses the spectral accuracy. Numerical results demonstrate its high efficiency. 相似文献
977.
丁协平 《应用数学和力学(英文版)》2001,22(2):160-172
IntroductionLetXandYbenonemptysetsand2 XbethefamilyofallsubsetsofX .LetT :X→Ybeasingle_valuedmapping ,A :X→ 2 Xbeaset_valuedmapping ,ψ :X×Y×X→R∪ ±∞ andf:X×Y→R∪ ±∞ betwofunctions.Thegeneralquasi_equilibriumproblemGQEP (T ,A ,ψ)istofind ^x∈Xsuchthat^x∈A( ^x) ,ψ( ^x ,T^x ,y)≤ 0… 相似文献
978.
IntroductionWeconsidertheextendedlinearcomplementarityproblem (XLCP)introducedbyMangasarianandPang[1](alsoseeYe[2 ]) :Findavector(x ,y) ∈R2nsuchthatMx-Ny∈K ,xTy=0 , x≥ 0 ,y≥ 0 ,( 1 )whereM ,N ∈Rm×naregiven ,andKisapolyhedralsetinRmdefinedbyK :=u∈Rm|Gu≥g , G∈Rl×m,g∈Rl.Thispro… 相似文献
979.
IntroductionAnumberofmaterialsinengineeringcanbeclassifiedinthecatalogofviscoelasticity ,includingrock ,soil,polymer,andER MRmaterialsetc .[Christensen 1 982 [1],TAO 1 999[2 ]] .Thedynamicanalysisofviscoelasticproblemsisrelatedtothetimedependentsolutions.Eventhoughdi… 相似文献
980.
Theauthorsstudiedaclassofsingularlyperturbedproblemsin [1 ] -[7] .Nowweraiseaclassofsingularlyperturbedproblemsonapartofdomain .Considerthefollowinginitialboundaryvalueproblemforthereactiondiffusionequations ut-λε(x) ( μ(u)ux) x Kx(u) f(x ,t,u) =0 ,(t,x) ∈ ( 0 ,T)× ( ( 0 ,α) ∪ (… 相似文献