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On the Motion of Controllable Mechanical Systems Having Variable Mass 被引量:1
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作者 朱海平 吴惠彬 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1994年第2期122-130,共9页
The differential equations of motion of a comtlaint system with parameters and variable mass, of a system with variable mass and servo constraints and those for the control problem on the forced motion of constraint s... The differential equations of motion of a comtlaint system with parameters and variable mass, of a system with variable mass and servo constraints and those for the control problem on the forced motion of constraint systems with variable mass are given respectively. Finally, an example is presented. 展开更多
关键词 variable mass systems/controllable mechanical system servo constraint forced motion
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A New Heat Transfer Model for Multi-Gradient Drilling with Hollow Sphere Injection
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作者 Jiangshuai Wang Chuchu Cai +3 位作者 Pan Fu Jun Li Hongwei Yang Song Deng 《Fluid Dynamics & Materials Processing》 EI 2024年第3期537-546,共10页
Multi-gradient drilling is a new offshore drilling method.The accurate calculation of the related wellbore temperature is of great significance for the prediction of the gas hydrate formation area and the precise cont... Multi-gradient drilling is a new offshore drilling method.The accurate calculation of the related wellbore temperature is of great significance for the prediction of the gas hydrate formation area and the precise control of the wellbore pressure.In this study,a new heat transfer model is proposed by which the variable mass flow is properly taken into account.Using this model,the effects of the main factors influencing the wellbore temperature are analyzed.The results indicate that at the position where the separation injection device is installed,the temperature increase of the fluid in the drill pipe is mitigated due to the inflow/outflow of hollow spheres,and the temperature drop of the fluid in the annulus also decreases.In addition,a lower separation efficiency of the device,a shallower installation depth and a smaller circulating displacement tend to increase the temperature near the bottom of the annulus,thereby helping to reduce the hydrate generation area and playing a positive role in the prevention and control of hydrates in deepwater drilling. 展开更多
关键词 Multi-gradient drilling wellbore temperature HYDRATE separate injection device variable mass
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Exact Invariants and Adiabatic Invariants of Nonholonomic Variable Mass Systems
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作者 陈向炜 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期131-137,共7页
By the theory of symmetries and conserved quantities, the exact invariants and adiabatic invariants of nonholonomic variable mass systems are studied. The perturbation problem of symmetries for the nonholonomic variab... By the theory of symmetries and conserved quantities, the exact invariants and adiabatic invariants of nonholonomic variable mass systems are studied. The perturbation problem of symmetries for the nonholonomic variable mass systems under small excitation is discussed. The concept of high order adiabatic invariant is presented, and the form of exact invariants and adiabatic invariants as well as the conditions for their existence are given. Then the corresponding inverse problem is studied. 展开更多
关键词 analytical mechanics variable mass PERTURBATION adiabatic invariant
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Unified symmetry of nonholonomic mechanical systems with variable mass 被引量:7
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作者 夏丽莉 李元成 +1 位作者 后其宝 王静 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第5期903-906,共4页
Based on the total time derivative along the trajectory of the system the definition and the criterion for a unified symmetry of nonholonomic mechanical system with variable mass are presented in this paper. A new con... Based on the total time derivative along the trajectory of the system the definition and the criterion for a unified symmetry of nonholonomic mechanical system with variable mass are presented in this paper. A new conserved quantity, as well as the Noether conserved quantity and the Hojman conserved quantity, deduced from the unified symmetry, are also obtained, An example is given to illustrate the application of the results. 展开更多
关键词 variable mass nonholonomic mechanical system unified symmetry conserved quantity
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Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion 被引量:5
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作者 张美玲 孙现亭 +2 位作者 王肖肖 解银丽 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期19-22,共4页
Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion are studied. The determining equation of Lie symmetry of Nielsen equations for a ... Lie symmetry and the generalized Hojman conserved quantity of Nielsen equations for a variable mass holonomic system of relative motion are studied. The determining equation of Lie symmetry of Nielsen equations for a variable mass holonomic system of relative motion under the infinitesimal transformations of groups is given. The expression of generalized Hojman conserved quantity deduced directly from Lie symmetry for a variable mass holonomic system of relative motion is obtained. An example is given to illustrate the application of the results. 展开更多
关键词 variable mass relative motion Lie symmetry generalized Hojman conserved quantity
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Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system of relative motion 被引量:3
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作者 张美玲 王肖肖 +1 位作者 韩月林 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第10期17-21,共5页
Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system of relative motion are studied.The definition and criterion of the Mei symmetry of Appell equations for a variable mass ... Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system of relative motion are studied.The definition and criterion of the Mei symmetry of Appell equations for a variable mass holonomic system of relative motion under the infinitesimal transformations of groups are given.The structural equation of Mei symmetry of Appell equations and the expression of Mei conserved quantity deduced directly from Mei symmetry for a variable mass holonomic system of relative motion are gained.Finally,an example is given to illustrate the application of the results. 展开更多
关键词 variable mass relative motion Appell equations Mei conserved quantity
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Mei Symmetry and Noether Symmetry of the Relativistic Variable Mass System 被引量:2
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作者 FANGJian-Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期349-352,共4页
The definition and criterion of the Mei symmetry of a relativistic variable mass system are given. The relation between the Mei symmetry and the Noether symmetry of the system is found under infinitesimal transformati... The definition and criterion of the Mei symmetry of a relativistic variable mass system are given. The relation between the Mei symmetry and the Noether symmetry of the system is found under infinitesimal transformations of groups. The conserved quantities to which the Mei symmetry and Noether symmetry of the system lead are obtained.An example is given to illustrate the application of the result. 展开更多
关键词 RELATIVITY variable mass system Mei symmetry Noether symmetry conserved quantity relativistic variable mass system
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Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system 被引量:2
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作者 崔金超 张耀宇 +1 位作者 杨新芳 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第3期31-35,共5页
Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system are investi- gated. Appell equations and differential equations of motion for a variable mass holonomic system are estab... Mei symmetry and Mei conserved quantity of Appell equations for a variable mass holonomic system are investi- gated. Appell equations and differential equations of motion for a variable mass holonomic system are established. A new expression of the total first derivative of the function with respect of time t along the systematic motional track curve, and the definition and the criterion of Mei symmetry for Appell equations under the infinitesimal transformations of groups are given. The expressions of the structural equation and Mei conserved quantity for Mei symmetry in Appell are obtained. An example is given to illustrate the application of the results. 展开更多
关键词 variable mass holonomic system Appell equation Mei symmetry Mei conserved quan-tity
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Variable mass and thermal properties in three-dimensional viscous flow: Application of Darcy law 被引量:2
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作者 Iffat JABEEN Muhammad FAROOQ Nazir A. MIR 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第5期1271-1282,共12页
This article concentrates on the properties of three-dimensional magneto-hydrodynamic flow of a viscous fluid saturated with Darcy porous medium deformed by a nonlinear variable thickened surface.Analysis of flow is d... This article concentrates on the properties of three-dimensional magneto-hydrodynamic flow of a viscous fluid saturated with Darcy porous medium deformed by a nonlinear variable thickened surface.Analysis of flow is disclosed in the neighborhood of stagnation point.Features of heat transport are characterized with Newtonian heating and variable thermal conductivity.Mass transport is carried out with first order chemical reaction and variable mass diffusivity.Resulting governing equations are transformed by implementation of appropriate transformations.Analytical convergent series solutions are computed via homotopic technique.Physical aspects of numerous parameters are discussed through graphical data.Drag force coefficient,Sherwood and Nusselt numbers are illustrated through graphs corresponding to various pertinent parameters.Graphical discussion reveals that conjugate and constructive chemical reaction parameters enhance the temperature and concentration distributions,respectively. 展开更多
关键词 Newtonian heating chemical reaction variable mass diffusivity Darcy law
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FIRST INTEGRALS AND INTEGRAL INVARIANTS FOR VARIABLE MASS NONHOLONOMIC SYSTEM IN NONINERTIAL REFERENCE FRAMES 被引量:2
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作者 罗绍凯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第2期147-154,共8页
The first integrals and their conditions of existence for variable massnonholonomic system in noninertial relerence frames are obtained,and the canonicalequations and the variation equations of the system are extended... The first integrals and their conditions of existence for variable massnonholonomic system in noninertial relerence frames are obtained,and the canonicalequations and the variation equations of the system are extended. It is proved that using the first integral we can construct the integral invariant of the system.Finally,a series of deductions and an example are given. 展开更多
关键词 analytical mechanics.nonholonomic constraint variable mass noninertial reference frame first integral.integral invanant
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Non-Noether Conserved Quantity for Relativistic Nonholonomic System with Variable Mass 被引量:1
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作者 QIAOYong-Fen LIRen-Jie MAYong-Sheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期197-200,共4页
Using form invariance under special infinitesimal transformations in which time is not variable, the non-Noether conserved quantity of the relativistic nonholonomic system with variable mass is studied. The differenti... Using form invariance under special infinitesimal transformations in which time is not variable, the non-Noether conserved quantity of the relativistic nonholonomic system with variable mass is studied. The differential equations of motion of the system are established. The definition and criterion of the form invariance of the system under infinitesimal transformations are studied. The necessary and sufficient. condition under which the form invariance is a Lie symmetry is given. The condition under which the form invariance can be led to a non-Noether. conserved quantity and the form of the conserved quantity are obtained. Finally, an example is given to illustrate the application of the result. 展开更多
关键词 analytical mechanics RELATIVITY nonholonomic system variable mass non-Noether conserved quantity
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Mei Symmetries and Lie Symmetries for Nonholonomic Controllable Mechanical Systems with Relativistic Rotational Variable Mass 被引量:1
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作者 XIA Li-Li LI Yuan-Cheng WANG Xian-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第6期1073-1077,共5页
The Mei symmetries and the Lie symmetries for nonholonomic controllable mechanical systems with relativistic rotational variable mass are studied. The differential equations of motion of the systems are established. ... The Mei symmetries and the Lie symmetries for nonholonomic controllable mechanical systems with relativistic rotational variable mass are studied. The differential equations of motion of the systems are established. The definition and criterion of the Mei symmetries and the Lie symmetries of the system are studied respectively. The necessary and sufficient condition under which the Mei symmetry is Lie symmetry is given. The condition under which the Mei symmetries can be led to a new kind of conserved quantity and the form of the conserved quantity are obtained. An example is given to illustrate the application of the results. 展开更多
关键词 relativity rotation nonholonomic controllable mechanical system variable mass conserved quantity
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Conformal invariance and conserved quantities of a general holonomic system with variable mass 被引量:1
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作者 夏丽莉 蔡建乐 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期25-30,共6页
Conformal invariance and conserved quantities of a general holonomic system with variable mass are studied. The definition and the determining equation of conformal invariance for a general holonomic system with varia... Conformal invariance and conserved quantities of a general holonomic system with variable mass are studied. The definition and the determining equation of conformal invariance for a general holonomic system with variable mass are provided. The conformal factor expression is deduced from conformal invariance and Lie symmetry. The relationship between the conformal invariance and the Lie symmetry is discussed, and the necessary and sufficient condition under which the conformal invariance would be the Lie symmetry of the system under an infinitesimal oneparameter transformation group is deduced. The conserved quantities of the system are given. An example is given to illustrate the application of the result. 展开更多
关键词 variable mass conformal invariance conformal factor conserved quantity
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The Lie symmetries and Noether conserved quantities of discrete mechanical systems with variable mass 被引量:1
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作者 施沈阳 傅景礼 +2 位作者 黄晓虹 陈立群 张晓波 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期754-758,共5页
This paper studies the Lie symmetries and Noether conserved quantities of discrete mechanical systems with variable mass. The discrete Euler-Lagrange equation and energy evolution equation are derived by using a total... This paper studies the Lie symmetries and Noether conserved quantities of discrete mechanical systems with variable mass. The discrete Euler-Lagrange equation and energy evolution equation are derived by using a total variational principle. The invariance of discrete equations under infinitesimal transformation groups is defined to be Lie symmetry. The condition of obtaining the Noether conserved quantities from the Lie symmetries is also presented. An example is discussed for applications of the results. 展开更多
关键词 discrete mechanics variable mass system Lie symmetry Noether conserved quantity
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Symmetry of Lagrangians of a holonomic variable mass system 被引量:1
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作者 吴惠彬 梅凤翔 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期335-338,共4页
The symmetry of Lagrangians of a holonomic variable mass system is studied. Firstly, the differential equations of motion of the system are established. Secondly, the definition and the criterion of the symmetry of th... The symmetry of Lagrangians of a holonomic variable mass system is studied. Firstly, the differential equations of motion of the system are established. Secondly, the definition and the criterion of the symmetry of the system are presented. Thirdly, the conditions under which there exists a conserved quantity deduced by the symmetry are obtained. The form of the conserved quantity is the same as that of the constant mass Lagrange system. Finally, an example is shown to illustrate the application of the result. 展开更多
关键词 Holonomic system variable mass system symmetry of Lagrangians conserved quantity
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THE LIE SYMMETRIES AND CONSERVED QUANTITIES OF VARIABLE-MASS NONHOLONOMIC SYSTEM OF NON-CHETAEV'S TYPE IN PHASE SPACE
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作者 方建会 赵嵩卿 焦志勇 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第10期1215-1220,共6页
The Lie symmetries and the conserved quantities of a variable mass nonholonomic system of non-Chetaev's type are studied by introducing the infinitesimal transformations of groups in phase space. By using the inva... The Lie symmetries and the conserved quantities of a variable mass nonholonomic system of non-Chetaev's type are studied by introducing the infinitesimal transformations of groups in phase space. By using the invariance of the differential equations of motion under the infinitesmal transformations of groups, the determining equations and the restriction equations of the Lie symmetries of the system are established, and the structure equations and the conserved quantities are obtained. An example is given to illustrate the application of the result. 展开更多
关键词 nonholonomic system phase space analytic mechanics variable mass Lie symmetry conserved quantity
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A New Type of Conserved Quantity of Mei Symmetry for Relativistic Variable Mass Mechanical System in Phase Space
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作者 ZHANG Xiao-Ni FANG Jian-Hui LIN Peng PANG Ting 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1145-1147,共3页
In this paper, a new type of conserved quantity directly deduced from the Mei symmetry for relativistic variable mass system in phase space is studied. The definition and the criterion of the Mei symmetry for the syst... In this paper, a new type of conserved quantity directly deduced from the Mei symmetry for relativistic variable mass system in phase space is studied. The definition and the criterion of the Mei symmetry for the system are given. The conditions for existence and the form of the new conserved quantity are obtained. Finally, an example is given to illustrate the application of the results. 展开更多
关键词 RELATIVITY variable mass system phase space Mei symmetry new conserved quantity
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Form Invariance and Conserved Quantity for Non-holonomic Systems with Variable Mass and Unilateral Constraints
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作者 WANG Jing LI Yuan-Cheng HOU Qi-Bao XIA Li-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期213-216,共4页
The paper studies the form invariance and a type of non-Noether conserved quantity called Mei conserved quantity for non-holonomic systems with variable mass and unilateral constraints. Acoording to the invariance of ... The paper studies the form invariance and a type of non-Noether conserved quantity called Mei conserved quantity for non-holonomic systems with variable mass and unilateral constraints. Acoording to the invariance of the form of differential equations of motion under infinitesimal transformations, this paper gives the definition and criterion of the form invariance for non-holonomic systems with variable mass and unilateral constraints. The condition under which a form invariance can lead to Mei conservation quantity and the form of the conservation quantity are deduced. An example is given to illustrate the application of the results. 展开更多
关键词 variable mass unilateral constraint non-holonomic system form invaxiance conserved quantity
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THE PRINCIPLES OF LEAST ACTION OF VARIABLE MASS NONHOLONOMIC NONCONSERVATIVE SYSTEM IN NONINERTIAL REFERENCE FRAMES
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作者 罗绍凯 梅凤翔 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第9期851-859,共9页
This paper presents the generalized principles of least action of variable mass nonholonomic nonconservative system in noninertial reference frame, proves the equivalence between Holder form and Suslov form, and then ... This paper presents the generalized principles of least action of variable mass nonholonomic nonconservative system in noninertial reference frame, proves the equivalence between Holder form and Suslov form, and then obtains differential equations of motion of variable mass nonholonomic nonconservative system in noninertial reference frame. 展开更多
关键词 analytical mechanics variable mass system nonholonomic constraints noninertial reference frame variational method principle of least action
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GIBBS-APPELL’S EQUATIONS OF VARIABLE MASS NONLINEAR NONHOLONOMIC MECHANICAL SYSTEMS
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作者 乔永芬 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第10期973-983,共11页
In this paper, the Gibbs-Appell's equations of motion are extended to the most general variable mass nonholonomie mechanical systems. Then the Gibbs-Appell's equations of motion in terms of generalized coordin... In this paper, the Gibbs-Appell's equations of motion are extended to the most general variable mass nonholonomie mechanical systems. Then the Gibbs-Appell's equations of motion in terms of generalized coordinates or quasi-coordinates and an integral variational principle of variable mass nonlinear nonholonomie mechanical systems are obtained. Finally, an example is given. 展开更多
关键词 variable mass nonholonomic system Gibbs-Appell's equation integral variational principle quasi-velocity
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