Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics最新文献_第8页

Causal implications of viscous damping in compressible fluid flows 可压缩流体流动中粘性阻尼的因果含义

Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics Pub Date : 2000-12-01 DOI: 10.1103/physreve.62.7918

Jordan, Meyer, Puri

{"title":"Causal implications of viscous damping in compressible fluid flows","authors":"Jordan, Meyer, Puri","doi":"10.1103/physreve.62.7918","DOIUrl":"https://doi.org/10.1103/physreve.62.7918","url":null,"abstract":"Classically, a compressible, isothermal, viscous fluid is regarded as a mathematical continuum and its motion is governed by the linearized continuity, Navier-Stokes, and state equations. Unfortunately, solutions of this system are of a diffusive nature and hence do not satisfy causality. However, in the case of a half-space of fluid set to motion by a harmonically vibrating plate the classical equation of motion can, under suitable conditions, be approximated by the damped wave equation. Since this equation is hyperbolic, the resulting solutions satisfy causal requirements. In this work the Laplace transform and other analytical and numerical tools are used to investigate this apparent contradiction. To this end the exact solutions, as well as their special and limiting cases, are found and compared for the two models. The effects of the physical parameters on the solutions and associated quantities are also studied. It is shown that propagating wave fronts are only possible under the hyperbolic model and that the concept of phase speed has different meanings in the two formulations. In addition, discontinuities and shock waves are noted and a physical system is modeled under both formulations. Overall, it is shown that the hyperbolic form gives a more realistic description of the physical problem than does the classical theory. Lastly, a simple mechanical analog is given and connections to viscoelastic fluids are noted. In particular, the research presented here supports the notion that linear compressible, isothermal, viscous fluids can, at least in terms of causality, be better characterized as a type of viscoelastic fluid.","PeriodicalId":20079,"journal":{"name":"Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics","volume":"62 6 Pt A","pages":"7918-26"},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1103/physreve.62.7918","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21959780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 57

Kinetic theory of dense fluids of rigid biaxial ellipsoids 刚性双轴椭球的致密流体动力学理论

Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics Pub Date : 2000-12-01 DOI: 10.1103/physreve.62.7927

Singh, Kumar

{"title":"Kinetic theory of dense fluids of rigid biaxial ellipsoids","authors":"Singh, Kumar","doi":"10.1103/physreve.62.7927","DOIUrl":"https://doi.org/10.1103/physreve.62.7927","url":null,"abstract":"The transport equation for a one-particle distribution function f of a pure and dense fluid composed of hard biaxial ellipsoids has been derived by the Enskog method through a modification of the Taxman equation which describes the corresponding low-density fluid. The equation for f has been utilized in obtaining approximate equations of continuity, linear momentum, and energy of the dense fluid, and has then been solved through the Enskog infinite series expansion technique, and a second-order approximate formula for f has been achieved. Using this, results are derived for the hydrodynamic pressure, shear and bulk viscosity coefficients, and heat conductivity of the fluid. Fast exchange of energy between the translational and rotational motions is assumed throughout the calculation. The quantities ultimately appearing in the results, which cannot further be reduced analytically and require numerical evaluation, are the four-dimensional quadratures over the orientational coordinates of two interacting rigid ellipsoidal molecules. In the appropriate limit, all results reduce to those obtained by Enskog for a dense fluid of hard spheres, and a first-order modified Eucken-type formula for the dense fluid emerges.","PeriodicalId":20079,"journal":{"name":"Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics","volume":"62 6 Pt A","pages":"7927-40"},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1103/physreve.62.7927","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21959781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Dielectric response of a polarizable system with quenched disorder 具有猝灭无序的极化系统的介电响应

Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics Pub Date : 2000-12-01 DOI: 10.1103/physreve.62.7949

Song, Chandler

引用次数: 1

Mean-field stochastic theory for species-rich assembled communities. 物种丰富聚集群落的平均场随机理论。

Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics Pub Date : 2000-12-01 DOI: 10.1103/physreve.62.8466

A McKane, D Alonso, R V Solé

{"title":"Mean-field stochastic theory for species-rich assembled communities.","authors":"A McKane, D Alonso, R V Solé","doi":"10.1103/physreve.62.8466","DOIUrl":"https://doi.org/10.1103/physreve.62.8466","url":null,"abstract":"A dynamical model of an ecological community is analyzed within a \"mean-field approximation\" in which one of the species interacts with the combination of all of the other species in the community. Within this approximation the model may be formulated as a master equation describing a one-step stochastic process. The stationary distribution is obtained in closed form, and is shown to reduce to a log-series or log-normal distribution, depending on the values that the parameters describing the model take on. A hyperbolic relationship between the connectance of the matrix of interspecies interactions and the average number of species exists for a range of parameter values. The time evolution of the model at short and intermediate times is analyzed using van Kampen's approximation, which is valid when the number of individuals in the community is large. Good agreement with numerical simulations is found. The large time behavior, and the approach to the stationary state, is obtained by solving the equation for the generating function of the probability distribution. The analytical results which follow from the analysis are also in good agreement with direct simulations of the model.","PeriodicalId":20079,"journal":{"name":"Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics","volume":"62 6 Pt B","pages":"8466-84"},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1103/physreve.62.8466","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21959787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 84

VUV absorption spectroscopy measurements of the role of fast neutral atoms in a high-power gap breakdown 紫外吸收光谱测量快中性原子在高功率间隙击穿中的作用

Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics Pub Date : 2000-12-01 DOI: 10.1103/physreve.62.8485

Filuk, Bailey, Cuneo, Lake, Nash, Noack, Maron

{"title":"VUV absorption spectroscopy measurements of the role of fast neutral atoms in a high-power gap breakdown","authors":"Filuk, Bailey, Cuneo, Lake, Nash, Noack, Maron","doi":"10.1103/physreve.62.8485","DOIUrl":"https://doi.org/10.1103/physreve.62.8485","url":null,"abstract":"The maximum power achieved in a wide variety of high-power devices, including electron and ion diodes, z pinches, and microwave generators, is presently limited by anode-cathode gap breakdown. A frequently discussed hypothesis for this effect is ionization of fast neutral atoms injected throughout the anode-cathode gap during the power pulse. We describe a newly developed diagnostic tool that provides a direct test of this hypothesis. Time-resolved vacuum-ultraviolet absorption spectroscopy is used to directly probe fast neutral atoms with 1-mm spatial resolution in the 10-mm anode-cathode gap of the SABRE 5 MV, 1 TW applied-B ion diode. Absorption spectra collected during Ar RF glow discharges and with CO2 gas fills confirm the reliability of the diagnostic technique. Throughout the 50-100 ns ion diode pulses no measurable neutral absorption was seen, setting upper limits of (0.12-1.5)x10(14) cm(-3) for ground-state fast neutral atom densities of H, C, N, O, and F. The absence of molecular absorption bands also sets upper limits of (0.16-1.2)x10(15) cm(-3) for common simple molecules. These limits are low enough to rule out ionization of fast neutral atoms as a breakdown mechanism. Breakdown due to ionization of molecules is also found to be unlikely. This technique can now be applied to quantify the role of neutral atoms in other high-power devices.","PeriodicalId":20079,"journal":{"name":"Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics","volume":"62 6 Pt B","pages":"8485-92"},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1103/physreve.62.8485","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21959788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Dust acoustic waves in strongly coupled dissipative plasmas 强耦合耗散等离子体中的尘埃声波

Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics Pub Date : 2000-12-01 DOI: 10.1103/physreve.62.8501

Xie, Yu

引用次数: 37

Two scaling domains in multiple cracking phenomena 多重裂纹现象中的两个标度域

Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics Pub Date : 2000-12-01 DOI: 10.1103/physreve.62.7807

Handge, Leterrier, Rochat, Sokolov, Blumen

引用次数: 28

Frictional-collisional regime for granular suspension flows down an inclined channel 颗粒状悬浮液沿倾斜通道流动的摩擦碰撞状态

Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics Pub Date : 2000-12-01 DOI: 10.1103/physreve.62.8349

Ancey, Evesque

引用次数: 63

Multistability and hysteresis phenomena in passive mode-locked lasers 被动锁模激光器中的多稳定性和迟滞现象

Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics Pub Date : 2000-12-01 DOI: 10.1103/physreve.62.r7607

Komarov, Komarov

引用次数: 38

Double-logarithmic finite-size scaling behavior of the specific heat does not necessarily imply its divergence 比热的双对数有限尺度行为并不一定意味着它的发散

Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics Pub Date : 2000-12-01 DOI: 10.1103/physreve.62.8798

Kim

引用次数: 0