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Why the Expansion of the Universe Appears to Accelerate
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作者 Paul Smeulders 《Journal of Modern Physics》 2013年第6期780-783,共4页
A Speed of Light falling over time inversely proportional to the expansion of the Universe leads to an experimentally observed exponential changing of the Red Shift over time. It is necessary to re-define the Angular ... A Speed of Light falling over time inversely proportional to the expansion of the Universe leads to an experimentally observed exponential changing of the Red Shift over time. It is necessary to re-define the Angular Impulse Momentum in order to get a consistent expansion of space on all levels. Conservation of Energy and this newly defined Angular Impulse Momentum then leads to the requirement that all clocks slow down in time inversely proportional to the Red Shift, independent of whether the Speed of Light is constant or not. From the Lorentz equation it then follows that Expansion occurs over space-time and not over space alone. A steady state expansion in true time is then transformed into an exponential expansion for an observer with a local clock. A finite lifetime of the Universe is transformed to an infinite lifetime for these observers including elementary particles. 展开更多
关键词 acceleration of expansion expansion of SPACE-TIME EXPONENTIAL expansion CONSERVATION LAWS DARK Energy
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Including Space-Time in the Extended Group Cl3* of Relativistic Form-Invariance
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作者 Claude Daviau Jacques Bertrand 《Journal of Modern Physics》 CAS 2022年第8期1147-1156,共10页
The inclusion of space-time in the extended group of relativistic form-invariance, Cl<sub>3</sub>*</sup>, is specified as the inclusion of the whole space-time manifold in this multiplicative Lie gro... The inclusion of space-time in the extended group of relativistic form-invariance, Cl<sub>3</sub>*</sup>, is specified as the inclusion of the whole space-time manifold in this multiplicative Lie group. First physical results presented here are: the geometric origin of the time arrow, a better understanding of the non-simultaneity in optics and a mainly geometric origin for the universe expansion, and its recent acceleration. 展开更多
关键词 Space-Time Manifold Invariance Group Standard Model acceleration of expansion
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Evidences for Varying Speed of Light with Time 被引量:1
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作者 Giuseppe Pipino 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第2期395-411,共17页
Aims: The paper explores the hypothesis that the speed of light c is decreasing over time at rate (dc/dt)=-H? c, H being the Hubble constant. This hypothesis differs from the so-called tired light, in which the veloci... Aims: The paper explores the hypothesis that the speed of light c is decreasing over time at rate (dc/dt)=-H? c, H being the Hubble constant. This hypothesis differs from the so-called tired light, in which the velocity c is supposed to vary during the journey of photons in the empty space for some frictional mechanism. In the hypothesis of the author the speed c, during this journey, is assumed constant. In this way the problems of the tired hypothesis are overcome. Methods: The paper links the variation dc/dt with the Hubble constant and infers a value of dc/dt from the difference between the value of the variation of the Earth-Moon distance measured by the Lunar Laser Ranging Experiment and the tidal effect. Results: Under the hypothesis c time varying, we explain: 1) The cosmological redshift. 2) The anomalous acceleration ap ≈ -8 × 10-10 m?sec-2, measured for some spacecrafts. 3) The high redshift of supernovae Ia, which seems to evidence an acceleration of the expansion of the universe. 4) The peripheral motion of stars in galaxies around their rotational centre. 5) The dilation of the light curves observed for supernovae Ia. 展开更多
关键词 Lunar Laser RANGING Experiment DILATION of Light Curves of SUPERNOVAE Ia REDSHIFT Hubble’s Law Dark Matter Abnormal acceleration acceleration of expansion of UNIVERSE
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Variable Speed of Light with Time and General Relativity
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作者 Giuseppe Pipino 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第2期742-760,共19页
In a previous article entitled: “Evidences for varying speed of light with time” [1], a series of observational evidence was presented in favor of the hypothesis that the speed of light varies with time according to... In a previous article entitled: “Evidences for varying speed of light with time” [1], a series of observational evidence was presented in favor of the hypothesis that the speed of light varies with time according to the relationship d<i>c</i>/d<i>t</i> = -<i>Hc</i>, where <i>H</i> is the Hubble constant which is considered a universal constant. In this paper we propose to elaborate on the observational evidence supporting the hypothesis, and to probe the consequences of this relationship on General Relativity. Also we will provide a theoretical justification of the previous relationship and we will show how from it we can deduce galactic velocity curves. We can deduce the important empirical Tully-Fisher relation linking these curves to the baryonic mass of the galaxy and we can justify the apparent accelerated expansion of the universe without intervening elusive entities such as dark matter and dark energy. 展开更多
关键词 Abnormal acceleration Modified Newtonian Dynamic Tully-Fisher Relation REDSHIFT Hubble’s Law Dark Matter Dilation of Light Curves of Supernovae Ia acceleration of expansion of Universe General Relativity
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吸积的宇宙
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作者 庄得新 《中原工学院学报》 CAS 2003年第B08期157-159,共3页
 提出一个新的宇宙起源模型.在该模型中,认为我们居住其中的宇宙外面仍然是一个物质的世界,可称之为广义宇宙.在广义宇宙中,我们的宇宙可以看作是其中的一个吸积黑洞.从广义宇宙的概念和宇宙是吸积的概念出发,可以得出宇宙由于本身引...  提出一个新的宇宙起源模型.在该模型中,认为我们居住其中的宇宙外面仍然是一个物质的世界,可称之为广义宇宙.在广义宇宙中,我们的宇宙可以看作是其中的一个吸积黑洞.从广义宇宙的概念和宇宙是吸积的概念出发,可以得出宇宙由于本身引力势能的原因在加速膨胀,不需要所谓的排斥能或暗能量,也回答了宇宙起源的问题. 展开更多
关键词 宇宙起源模型 吸积 膨胀势能场 黑洞 宇宙模型 加速膨胀 暗能量
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On a Fractal Version of Witten’s M-Theory 被引量:12
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作者 Mohamed S. El Naschie 《International Journal of Astronomy and Astrophysics》 2016年第2期135-144,共10页
Starting from Witten’s eleven dimensional M-theory, the present work develops in an analogous way a corresponding dimensional fractal version where . Subsequently, the new fractal formalism is utilized to determine t... Starting from Witten’s eleven dimensional M-theory, the present work develops in an analogous way a corresponding dimensional fractal version where . Subsequently, the new fractal formalism is utilized to determine the measured ordinary energy density of the cosmos which turns out to be intimately linked to the new theory’s fractal dimension via non-integer irrational Lorentzian-like factor: where is Hardy’s probability of quantum entanglement. Consequently, the energy density is found from a limiting classical kinetic energy to be Here, is ‘tHooft’s renormalon of dimensional regularization. The immediate logical, mathematical and physical implication of this result is that the dark energy density of the cosmos must be in astounding agreement with cosmic measurements and observations. 展开更多
关键词 M-THEORY E-Infinity Theory Hardy’s Quantum Entanglement Transfinite Turing Computer Dark Energy accelerated Cosmic expansion Noncommutative Geometry Superstring Theory Scale Relativity Cantorian-Fractal Spacetime Witten’s Theory ‘tHooft Renormalon Pure Gravity Penrose Tiling
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Cosmic Dark Energy Density from Classical Mechanics and Seemingly Redundant Riemannian Finitely Many Tensor Components of Einstein’s General Relativity 被引量:8
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作者 Mohamed El Naschie 《World Journal of Mechanics》 2014年第6期153-156,共4页
We determine the limit of the ratio formed by the independent components of the Riemann tensor to the non-zero component as space dimensionality tends to infinity and find it to be 12. Subsequently we use this result ... We determine the limit of the ratio formed by the independent components of the Riemann tensor to the non-zero component as space dimensionality tends to infinity and find it to be 12. Subsequently we use this result in conjunction with Newtonian classical mechanics to show that the ordinary measurable cosmic energy density is given by while the dark energy density is obviously the Legendre transformation dual energy E(D) = 1 -?E(O). The result is in complete agreement with the COBE, WMAP and type 1a supernova measurements. 展开更多
关键词 Semi Classical Quantum Systems Dark Energy accelerated COSMIC expansion RIEMANNIAN TENSOR Infinite Dimensional Topology NONLOCAL Elasticity
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Cantorian-Fractal Kinetic Energy and Potential Energy as the Ordinary and Dark Energy Density of the Cosmos Respectively 被引量:4
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作者 Mohamed S. El Naschie 《Natural Science》 2016年第12期511-540,共30页
In a one-dimension Mauldin-Williams Random Cantor Set Universe, the Sigalotti topological speed of light is  where . It follows then that the corresponding topological acceleration must be a golden mean downscali... In a one-dimension Mauldin-Williams Random Cantor Set Universe, the Sigalotti topological speed of light is  where . It follows then that the corresponding topological acceleration must be a golden mean downscaling of c namely . Since the maximal height in the one-dimensional universe must be where is the unit interval length and note that the topological mass (m) and topological dimension (D) where m = D = 5 are that of the largest unit sphere volume, we can conclude that the potential energy of classical mechanics translates to . Remembering that the kinetic energy is , then by the same logic we see that  when m = 5 is replaced by for reasons which are explained in the main body of the present work. Adding both expressions together, we find Einstein’s maximal energy . As a general conclusion, we note that within high energy cosmology, the sharp distinction between potential energy and kinetic energy of classical mechanics is blurred on the cosmic scale. Apart of being an original contribution, the article presents an almost complete bibliography on the Cantorian-fractal spacetime theory. 展开更多
关键词 Potential Dark Energy Kinetic Ordinary Energy Motion as Illusion Zenonparadoxa E-Infinity Theory Noncommutative Geometry Topological acceleration Cantorian Universe accelerated Cosmic expansion
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From a Dual Einstein-Kaluza Spacetime to ‘tHooft Renormalon and the Reality of Accelerated Cosmic Expansion 被引量:4
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作者 Mohamed S. El Naschie 《Journal of Modern Physics》 2017年第8期1319-1329,共11页
We use a dual Einstein-Kaluza spacetime to calculate the exact energy density of dark energy and dark matter using a novel topological computation method. Starting from the said spacetime and ‘tHooft’s topological r... We use a dual Einstein-Kaluza spacetime to calculate the exact energy density of dark energy and dark matter using a novel topological computation method. Starting from the said spacetime and ‘tHooft’s topological renormalon as well as the corresponding symmetry group, we show how the zero set quantum particle and the empty set quantum wave interact with the vacuum and give rise to pure dark energy and pure dark matter all along with ordinary energy density of the cosmos. The consistency of the exact calculation and the accurate observations attests to the reality of ‘tHooft’s renormalon dark matter, pure dark energy and accelerated cosmic expansion. 展开更多
关键词 accelerated COSMIC expansion tHooft Renormalon Cantorian SPACETIME DARK Matter Pure DARK ENERGY Topological E-Infinity Computation Zero Set Quantum Particle Empty Set Quantum Wave Hausdorff MASS of Ordinary ENERGY Topological MASS of DARK ENERGY Mixed MASS of DARK Matter and Pure DARK ENERGY A Dual Einstein-Kaluza SPACETIME
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Kähler Dark Matter, Dark Energy Cosmic Density and Their Coupling 被引量:2
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作者 Mohamed S. El Naschie 《Journal of Modern Physics》 2016年第14期1953-1962,共11页
We utilize homology and co-homology of a K3-K&#228;hler manifold as a model for spacetime to derive the cosmic energy density of our universe and subdivide it into its three fundamental constituents, namely: 1) or... We utilize homology and co-homology of a K3-K&#228;hler manifold as a model for spacetime to derive the cosmic energy density of our universe and subdivide it into its three fundamental constituents, namely: 1) ordinary energy;2) pure dark energy and 3) dark matter. In addition, the fundamental coupling of dark matter to pure dark energy is analyzed in detail for the first time. Finally, the so-obtained results are shown to be in astounding agreement with all previous theoretical analysis as well as with actual accurate cosmic measurements. 展开更多
关键词 Kähler Topology Dark Matter E-INFINITY Super Strings Golden Mean Computer Kerr Black Hole Geometry accelerated Cosmic expansion Fractal Cantorian Spacetime
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Quantum Dark Energy from the Hyperbolic Transfinite Cantorian Geometry of the Cosmos 被引量:1
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作者 Mohamed S. El Naschie 《Natural Science》 2016年第3期152-159,共8页
The quintessence of hyperbolic geometry is transferred to a transfinite Cantorian-fractal setting in the present work. Starting from the building block of E-infinity Cantorian spacetime theory, namely a quantum pre-pa... The quintessence of hyperbolic geometry is transferred to a transfinite Cantorian-fractal setting in the present work. Starting from the building block of E-infinity Cantorian spacetime theory, namely a quantum pre-particle zero set as a core and a quantum pre-wave empty set as cobordism or surface of the core, we connect the interaction of two such self similar units to a compact four dimensional manifold and a corresponding holographic boundary akin to the compactified Klein modular curve with SL(2,7) symmetry. Based on this model in conjunction with a 4D compact hy- perbolic manifold M(4) and the associated general theory, the so obtained ordinary and dark en- ergy density of the cosmos is found to be in complete agreement with previous analysis as well as cosmic measurements and observations such as WMAP and Type 1a supernova. 展开更多
关键词 Dark Energy accelerated Cosmic expansion Hyperbolic Geometry Fractal Geometry Transfinite set Theory ‘tHooft Dimensional Regularization Hardy’s Quantum Entanglement Davis Hyperbolic Manifold Compactified Klein Modular Curve Fractal Counting Lie Symmetry Groups Stein Spaces
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On a Quantum Gravity Fractal Spacetime Equation: QRG ≃HD + FG and Its Application to Dark Energy—Accelerated Cosmic Expansion 被引量:1
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作者 Mohamed S. El Naschie 《Journal of Modern Physics》 2016年第8期729-736,共8页
The paper suggests that quantum relativistic gravity (QRG) is basically a higher dimensionality (HD) simulating relativity and non-classical effects plus a fractal Cantorian spacetime geometry (FG) simulating quantum ... The paper suggests that quantum relativistic gravity (QRG) is basically a higher dimensionality (HD) simulating relativity and non-classical effects plus a fractal Cantorian spacetime geometry (FG) simulating quantum mechanics. This more than just a conceptual equation is illustrated by integer approximation and an exact solution of the dark energy density behind cosmic expansion. 展开更多
关键词 Fractal Cantorian Spacetime Quantum Relativity Superstrings Transfinite Set Theory Extra Spacetime Dimensions Quantum Physics Dark Energy accelerated Cosmic expansion Cosmic Topology Hyperbolic Geometry E-Infinity Theory Post Modernistic Physics
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Negative Norms in Quantized Strings as Dark Energy Density of the Cosmos 被引量:1
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作者 Mohamed S. El Naschie 《World Journal of Condensed Matter Physics》 CAS 2016年第2期63-67,共5页
The present short paper is concerned with accurate explanation as well as quantification of the so called missing dark energy of the cosmos. It was always one of the main objectives of any successful general theory of... The present short paper is concerned with accurate explanation as well as quantification of the so called missing dark energy of the cosmos. It was always one of the main objectives of any successful general theory of high energy particle physics and quantum cosmology to keep non-physical negative norms, the so called ghosts completely out of that theory. The present work takes the completely contrary view by admitting these supposedly spurious states as part of the physical Hilbert space. It is further shown that rethinking the ghost free condition with the two critical spacetime dimensions D<sub>1</sub> = 26 and D<sub>2</sub> = 25 together with the corresponding intercept a<sub>1</sub> = 1 and a<sub>2</sub> ≤ 1 respectively and in addition imposing, as in Gross et al. heterotic superstrings, an overall 496 dimensional exceptional Lie symmetry group, then one will discover that there are two distinct types of energy. The first is positive norm ordinary energy connected to the zero set quantum particles which is very close to the measured ordinary energy density of the cosmos, namely E(O) = mc<sup>2</sup>/22. The second is negative norm (i.e. ghost) energy connected to the empty set quantum wave and is equal to the conjectured dark energy density of the cosmos E(D) = mc<sup>2</sup> (21/22) presumed to be behind the observed accelerated cosmic expansion. That way we were able to not only explain the physics of dark energy without adding any new concepts or novel additional ingredients but also we were able to compute the dark energy density accurately and in full agreement with measurements and observations. 展开更多
关键词 Negative Norms Quantum Ghosts Dark Energy accelerated Cosmic expansion SUPERSTRINGS Quantum Field Theory Cantorian-Fractal Spacetime Einstein Relativity Non-Fictional Spurions
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Cosmic Dark Energy from ‘t Hooft’s Dimensional Regularization and Witten’s Topological Quantum Field Pure Gravity 被引量:1
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作者 Mohamed S. El Naschie 《Journal of Quantum Information Science》 2014年第2期83-91,共9页
We utilize two different theories to prove that cosmic dark energy density is the complimentary Legendre transformation of ordinary energy and vice versa as given by E(dark) = mc2 (21/22) and E(ordinary) = mc2/22. The... We utilize two different theories to prove that cosmic dark energy density is the complimentary Legendre transformation of ordinary energy and vice versa as given by E(dark) = mc2 (21/22) and E(ordinary) = mc2/22. The first theory used is based on G ‘t Hooft’s remarkably simple renormalization procedure in which a neat mathematical maneuver is introduced via the dimensionality of our four dimensional spacetime. Thus, ‘t Hooft used instead of D = 4 and then took at the end of an intricate and subtle computation the limit to obtain the result while avoiding various problems including the pole singularity at D = 4. Here and in contradistinction to the classical form of dimensional and renormalization we set and do not take the limit where and is the theoretically and experimentally well established Hardy’s generic quantum entanglement. At the end we see that the dark energy density is simply the ratio of and the smooth disentangled D = 4, i.e. (dark) = (4 -k)/4 = 3.8196011/4 = 0.9549150275. Consequently where we have ignored the fine structure details by rounding 21 + k to 21 and 22 + k to 22 in a manner not that much different from of the original form of dimensional regularization theory. The result is subsequently validated by another equally ingenious approach due mainly to E. Witten and his school of topological quantum field theory. We notice that in that theory the local degrees of freedom are zero. Therefore, we are dealing essentially with pure gravity where are the degrees of freedom and is the corresponding dimension. The results and the conclusion of the paper are summarized in Figure 1-3, Table 1 and Flow Chart 1. 展开更多
关键词 accelerated COSMIC expansion 't Hooft-Veltman Dimensional Regularization Wilson RENORMALIZATION PURE GRAVITY Witten’s TOPOLOGICAL Quantum Field E-INFINITY Cantorian Spacetime
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含复杂细节结构的金属目标电磁散射ACE-MLFMA分析 被引量:2
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作者 付欣 聂在平 何十全 《微波学报》 CSCD 北大核心 2012年第S3期5-8,共4页
多层快速多极子算法(MLFMA)在计算含复杂细节结构目标的散射问题时,求解效率会迅速下降。本文介绍了快速笛卡尔展开(ACE)算法及其与MLFMA的结合,使得原先MLFMA的最细层能够再局部细分,加速了阻抗矩阵的填充和迭代求解。本文将该混合算... 多层快速多极子算法(MLFMA)在计算含复杂细节结构目标的散射问题时,求解效率会迅速下降。本文介绍了快速笛卡尔展开(ACE)算法及其与MLFMA的结合,使得原先MLFMA的最细层能够再局部细分,加速了阻抗矩阵的填充和迭代求解。本文将该混合算法应用于求解含复杂细节结构目标的电磁散射问题,包括具有尖端的杏仁核和由复杂带线结构构成的频率选择表面,计算实例验证了该方法求解效率的提高和内存开销的减少,以及算法的可靠性和高效性。 展开更多
关键词 细节结构 电磁散射 快速算法 快速笛卡尔展开
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以特大负能反正物质星体为中心的正反物质对称宇宙模型 被引量:1
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作者 葛旭初 《淮北煤师院学报(自然科学版)》 2000年第1期20-27,共8页
本文在以前研究的基础上进一步考虑了负能反正物质星体的作用,提出了以特大负能反正物质星体为中心的正反物质对称宇宙模型,对宇宙的加速膨胀和我们宇宙的接近临界态的膨胀与微波背景辐射的“天空大余弦”
关键词 负能反正物质星体 加速膨胀 宇宙模型 正反物质
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Newtonian Quantum Gravity
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作者 Jorge Gabriel Ales Corona 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第4期715-726,共12页
The quantum treatment of gravity has been researched for more than fifty years. The focus of the efforts was the investigation of the “gravitational quantum field” concept. This article paves the way to solving this... The quantum treatment of gravity has been researched for more than fifty years. The focus of the efforts was the investigation of the “gravitational quantum field” concept. This article paves the way to solving this puzzle. Gravity is a phenomenon that emerges from the undulating nature of the universe. To support this claim, I deduce a more generalized expression than that of Newton’s gravity from simple considerations relating to the wave function, the probability density function, and a hypothesis of how all particles in the universe are related. This expression uncovers the true nature of the gravitational phenomenon, dark matter, and dark energy. This true nature of the gravitational field allows its renormalization and the definition of its elementary charge. The result obtained considers the Mach’s principle and deduces the origin of the inertial force. Finally, it is concluded that a new model of the universe is necessary. 展开更多
关键词 Extended Theories of Gravity DARK Energy DARK MATTER Black HOLES accelerated COSMIC expansion RENORMALIZATION
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Absolute Maximum Proper Time to an Initial Event, the Curvature of Its Gradient along Conflict Strings and Matter
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作者 Eytan H. Suchard 《Journal of Modern Physics》 2013年第6期791-806,共16页
Einstein equation of gravity has on one side the momentum energy density tensor and on the other, Einstein tensor which is derived from Ricci curvature tensor. A better theory of gravity will have both sides geometric... Einstein equation of gravity has on one side the momentum energy density tensor and on the other, Einstein tensor which is derived from Ricci curvature tensor. A better theory of gravity will have both sides geometric. One way to achieve this goal is to develop a new measure of time that will be independent of the choice of coordinates. One natural nominee for such time is the upper limit of measurable time form an event back to the big bang singularity. This limit should exist despite the singularity, otherwise the cosmos age would be unbounded. By this, the author constructs a scalar field of time. Time, however, is measured by material clocks. What is the maximal time that can be measured by a small microscopic clock when our curve starts at near the “big bang” event and ends at an event within the nucleus of an atom? Will our tiny clock move along geodesic curves or will it move in a non geodesic curve within matter? It is almost paradoxical that a test particle in General Relativity will always move along geodesic curves but the motion of matter within the particle may not be geodesic at all. For example, the ground of the Earth does not move at geodesic velocity. Where there is no matter, we choose a curve from near “big bang” to an event such that the time measured is maximal. Without assuming force fields, the gravitational field which causes that two or more such curves intersect at events, would cause discontinuity of the gradient of the upper limit of measurable time scalar field. The discontinuity can be avoided only if we give up on measurement along geodesic curves where there is matter. In other words, our tiny test particle clock will experience force when it travels within matter or near matter. 展开更多
关键词 FOLIATION FIELD CURVATURE General RELATIVITY accelerated Cosmic expansion Quantum Gravity Dark MATTER CHAMELEON Scalar FIELD
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求解多尺度目标电磁散射的积分方程快速算法 被引量:2
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作者 郑宇腾 赵延文 +2 位作者 贾苗苗 蔡强明 聂在平 《电波科学学报》 EI CSCD 北大核心 2014年第4期601-605,共5页
多层快速卡特森展开算法(Multilevel Accelerated Cartesian Expansion Algorithm,MLACEA)可用于加速电小尺寸结构积分方程矩量法,且矩阵与矢量乘积运算计算复杂度为O(N)量级;MLACEA和多层快速多级子算法(Multilevel Fast Multipole Alg... 多层快速卡特森展开算法(Multilevel Accelerated Cartesian Expansion Algorithm,MLACEA)可用于加速电小尺寸结构积分方程矩量法,且矩阵与矢量乘积运算计算复杂度为O(N)量级;MLACEA和多层快速多级子算法(Multilevel Fast Multipole Algorithm,MLFMA)均基于八叉树分组结构,便于实现它们的混合快速算法MLACEA-MLFMA.该混合算法可大幅度降低模拟含精细结构的电大尺寸目标宽带电磁散射问题的计算复杂度.还详细阐述了求解电场积分方程的MLACEA算法及其与MLFMA算法的混合快速算法MLACEA-MLFMA算法;并通过计算实例对比分析了MLFMA算法与MLACEA-MLFMA混合算法的计算效率. 展开更多
关键词 多尺度问题 多层快速卡特森展开算法 多层快速多极子算法
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非线性弹性转子-轴承系统稳定裕度数值分析 被引量:1
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作者 刘继华 陈立 +2 位作者 罗载奇 李奕新 钱兴良 《燃气涡轮试验与研究》 北大核心 2015年第6期39-44,共6页
基于互补群群际能量壁垒准则量化理论,提出了轨迹加速度-位移扩展相平面稳定裕度分析法,从理论分析、数值计算两方面验证了该方法的正确性。建立了采用Capone圆轴承非线性油膜力模型的弹性转子-轴承系统模型,并用数值积分和庞加莱映射方... 基于互补群群际能量壁垒准则量化理论,提出了轨迹加速度-位移扩展相平面稳定裕度分析法,从理论分析、数值计算两方面验证了该方法的正确性。建立了采用Capone圆轴承非线性油膜力模型的弹性转子-轴承系统模型,并用数值积分和庞加莱映射方法,得到系统在某些参数域中的分岔图、轴心轨迹图、庞加莱映射图、时间历程图和频谱图,得出分岔失稳速度随质量偏心的变化规律:分岔速度随质量偏心的趋势是先减小后增大,拟合曲线符合三次高斯公式,拟合精度达0.998 2。数值分析结果为该类转子-轴承系统的设计和安全运行提供了理论参考。 展开更多
关键词 旋转机械 转子-轴承系统 加速度-位移扩展相平面 非线性 稳定裕度 分岔失稳转速 质量偏心
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