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Hypothetical Dark Matter Explains the Origin of Subatomic Universe: FEP-Theory
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作者 Ali Moghaddasi Hassan Yousefnia 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1643-1654,共12页
Although the standard model provides a suitable pattern based on observable experimental data, it cannot explain dark matter, gravitation, the structural nature of the fundamental particles, and charges. In this paper... Although the standard model provides a suitable pattern based on observable experimental data, it cannot explain dark matter, gravitation, the structural nature of the fundamental particles, and charges. In this paper, a new theory about the nature of charges, particles and proposed structures for atoms were presented. This theory explains how an ideal quantum fluid (IQF) including hypothetical dark matter or fundamental elementary particles (FEPs) can produce the building blocks of matter. This theory describes quadruple blocks with two types of independent charges that can create different characteristics for these building blocks. Quadruple blocks have similarities and differences with the fundamental particles in standard model. This theory also explains the possible mechanism of creation the next generation of particles such as protons and neutrons. 展开更多
关键词 theory Statistical Thermodynamics Ideal Quantum fluid Fundamental Elementary Particles
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Rigidity Symmetry Line for Thermodynamic Fluid Equations-of-State
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作者 Leslie V. Woodcock 《Journal of Modern Physics》 2024年第5期613-633,共21页
We report progress towards a modern scientific description of thermodynamic properties of fluids following the discovery (in 2012) of a coexisting critical density hiatus and a supercritical mesophase defined by perco... We report progress towards a modern scientific description of thermodynamic properties of fluids following the discovery (in 2012) of a coexisting critical density hiatus and a supercritical mesophase defined by percolation transitions. The state functions density ρ(p,T), and Gibbs energy G(p,T), of fluids, e.g. CO<sub>2</sub>, H<sub>2</sub>O and argon exhibit a symmetry characterised by the rigidity, ω = (dp/dρ)<sub>T</sub>, between gaseous and liquid states along any isotherm from critical (T<sub>c</sub>) to Boyle (T<sub>B</sub>) temperatures, on either side of the supercritical mesophase. Here, using experimental data for fluid argon, we investigate the low-density cluster physics description of an ideal dilute gas that obeys Dalton’s partial pressure law. Cluster expansions in powers of density relate to a supercritical liquid-phase rigidity symmetry (RS) line (ω = ρ<sub>rs</sub>(T) = RT) to gas phase virial coefficients. We show that it is continuous in all derivatives, linear within stable fluid phase, and relates analytically to the Boyle-work line (BW) (w = (p/ρ)<sub>T</sub> = RT), and to percolation lines of gas (PB) and liquid (PA) phases by: ρ<sub>BW</sub>(T) = 2ρ<sub>PA</sub>(T) = 3ρ<sub>PB</sub>(T) = 3ρ<sub>RS</sub>(T)/2 for T T<sub>B</sub>. These simple relationships arise, because the higher virial coefficients (b<sub>n</sub>, n ≥ 4) cancel due to clustering equilibria, or become negligible at all temperatures (0 T T<sub>B</sub>)<sub> </sub>within the gas phase. The Boyle-work line (p/ρ<sub>BW</sub>)<sub>T</sub> is related exactly at lower densities as T → T<sub>B</sub>, and accurately for liquid densities, by ρ<sub>BW</sub>(T) = −(b<sub>2</sub>/b<sub>3</sub>)<sub>T</sub>. The RS line, ω(T) = RT, defines a new liquid-density ground-state physical constant (ρ<sub>RS</sub>(0) = (2/3)ρ<sub>BW</sub>(0) for argon). Given the gas-liquid rigidity symmetry, the entire thermodynamic state functions below T<sub>B</sub> are obtainable from b<sub>2</sub>(T). A BW-line ground-state crystal density ρ<sub>BW</sub>(0) can be defined by the pair potential minimum. The Ar<sub>2</sub> pair potential, ∅ij</sub>(r<sub>ij</sub>) determines b<sub>2</sub>(T) analytically for all T. This report, therefore, advances the salient objective of liquid-state theory: an argon p(ρ,T) Equation-of-state is obtained from ∅<sub>ij</sub>(r<sub>ij</sub>) for all fluid states, without any adjustable parameters. 展开更多
关键词 Liquid-State theory Cluster Physics Percolation Lines fluid Thermodynamics Boyle Line Rigidity-Symmetry Line
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Von Kármán rotating flow of Maxwell nanofluids featuring the Cattaneo-Christov theory with a Buongiorno model 被引量:1
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作者 A.AHMED M.KHAN +1 位作者 J.AHMED A.HAFEEZ 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第8期1195-1208,共14页
This research paper analyzes the transport of thermal and solutal energy in the Maxwell nanofluid flow induced above the disk which is rotating with a constant angular velocity.The significant features of thermal and ... This research paper analyzes the transport of thermal and solutal energy in the Maxwell nanofluid flow induced above the disk which is rotating with a constant angular velocity.The significant features of thermal and solutal relaxation times of fluids are studied with a Cattaneo-Christov double diffusion theory rather than the classical Fourier’s and Fick’s laws.A novel idea of a Buongiorno nanofluid model together with the Cattaneo-Christov theory is introduced for the first time for the Maxwell fluid flow over a rotating disk.Additionally,the thermal and solutal distributions are controlled with the impacts of heat source and chemical reaction.The classical von Karman similarities are used to acquire the non-linear system of ordinary differential equations(ODEs).The analytical series solution to the governing ODEs is obtained with the well-known homotopy analysis method(HAM).The validation of results is provided with the published results by the comparison tables.The graphically presented outcomes for the physical problem reveal that the higher values of the stretching strength parameter enhance the radial velocity and decline the circumferential velocity.The increasing trend is noted for the axial velocity profile in the downward direction with the higher values of the stretching strength parameter.The higher values of the relaxation time parameters in the Cattaneo-Christov theory decrease the thermal and solutal energy transport in the flow of Maxwell nanoliquids.The higher rate of the heat transport is observed in the case of a larger thermophoretic force. 展开更多
关键词 Maxwell fluid NANOPARTICLE Cattaneo-Christov theory rotating disk homotopy analysis method(HAM)
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THE GLOBAL EXISTENCE OF STRONG SOLUTIONS FOR A NON-ISOTHERMAL IDEAL GAS SYSTEM
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作者 韩斌 赖宁安 Andrei TARFULEA 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期865-886,共22页
We investigate the global existence of strong solutions to a non-isothermal ideal gas model derived from an energy variational approach.We first show the global wellposedness in the Sobolev space H^(2)(R^(3)) for solu... We investigate the global existence of strong solutions to a non-isothermal ideal gas model derived from an energy variational approach.We first show the global wellposedness in the Sobolev space H^(2)(R^(3)) for solutions near equilibrium through iterated energy-type bounds and a continuity argument.We then prove the global well-posedness in the critical Besov space B^(3/2)_(2,1) by showing that the linearized operator is a contraction mapping under the right circumstances. 展开更多
关键词 thermal fluid equations energy-variational method well-posedness theory for PDE paraproduct calculus
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Numerical Simulation of the Settling Flux of Biodeposition in a Bay with Cage Culture Through Similarity Theory and a Simplified Pollution Source
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作者 LIU Yao CHEN Yifan GE Changzi 《Journal of Ocean University of China》 CAS CSCD 2024年第1期247-254,共8页
The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying capacity.Simple and effective simulation of the settling flux of biodeposition is ... The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying capacity.Simple and effective simulation of the settling flux of biodeposition is extremely important for determining the spatial distribution of biodeposition.Theoretically,biodeposition in cage culture areas without specific emission rules can be simplified as point source pollution.Fluent is a fluid simulation software that can simulate the dispersion of particulate matter simply and efficiently.Based on the simplification of pollution sources and bays,the settling flux of biodeposition can be easily and effectively simulated by Fluent fluid software.In the present work,the feasibility of this method was evaluated by simulation of the settling flux of biodeposition in Maniao Bay,Hainan Province,China,and 20 sampling sites were selected for determining the settling fluxes.At sampling sites P1,P2,P3,P4,P5,Z1,Z2,Z3,Z4,A1,A2,A3,A4,B1,B2,C1,C2,C3 and C4,the measured settling fluxes of biodeposition were 26.02,15.78,10.77,58.16,6.57,72.17,12.37,12.11,106.64,150.96,22.59,11.41,18.03,7.90,19.23,7.06,11.84,5.19 and 2.57 g d^(−1)m^(−2),respectively.The simulated settling fluxes of biodeposition at the corresponding sites were 16.03,23.98,8.87,46.90,4.52,104.77,16.03,8.35,180.83,213.06,39.10,17.47,20.98,9.78,23.25,7.84,15.90,6.06 and 1.65 g d^(−1)m^(−2),respectively.There was a positive correlation between the simulated settling fluxes and measured ones(R=0.94,P=2.22×10^(−9)<0.05),which implies that the spatial differentiation of biodeposition flux was well simulated.Moreover,the posterior difference ratio of the simulation was 0.38,and the small error probability was 0.94,which means that the simulated results reached an acceptable level from the perspective of relative error.Thus,if nonpoint source pollution is simplified to point source pollution and open waters are simplified based on similarity theory,the setting flux of biodeposition in the open waters can be simply and effectively simulated by the fluid simulation software Fluent. 展开更多
关键词 fluent fluid simulation software pollution source simplification posterior difference ratio similarity theory Spear-man correlation
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Investigation of vapour-liquid nucleation properties for spherical and chain-like fluids by density functional theory
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作者 付东 廖涛 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第11期3475-3482,共8页
The excess Helmholtz free energy functional for nonpolar chain-like molecules is formulated in terms of a weighted density approximation (WDA) for short-range interactions and a Weaks Chandler Andersen (WCA) appro... The excess Helmholtz free energy functional for nonpolar chain-like molecules is formulated in terms of a weighted density approximation (WDA) for short-range interactions and a Weaks Chandler Andersen (WCA) approximation and a Barker Henderson (BH) theory for long-range attraction. Within the framework of density functional theory (DFT), vapour liquid interracial properties including density profile and surface tension, and vapour-liquid nucleation properties including density profile, work of formation and number of particles are investigated for spherical and chain- like molecules. The obtained vapour liquid surface tension and the number of particles in critical nucleus for Lennard- Jones (L J) fluids are consistent with the simulation results. The influences of supersaturation, temperature and chain length on vapour liquid nucleation properties are discussed. 展开更多
关键词 vapour liquid nucleation chain like fluids density functional theory
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Study on the Phase Equilibria of Hard Core Asakura-Oosawa Fluids with Renormalization-group Theory
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作者 付东 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第4期463-469,共7页
An analytical equation of state (EOS) for hard core Asakura-Oosawa (AO) fluid is established by combining the AO potential, the first-order perturbation theory and the radial distribution function (RDF) for the hard s... An analytical equation of state (EOS) for hard core Asakura-Oosawa (AO) fluid is established by combining the AO potential, the first-order perturbation theory and the radial distribution function (RDF) for the hard sphere fluid.The phase equilibria are studied by using the renormalization-group (RG) theory. The obtained results agree well with the simulation data. Investigation shows that the attractive range parameter plays an important role in the phase equilibria for AO fluid. 展开更多
关键词 Asakura-Oosawa fluid equation of state phase equilibria renormalization-group theory
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基于加压酸浸锰烟尘过程中固-液两相流体力学特性CFD模拟
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作者 张强 梅洋 谢红艳 《菏泽学院学报》 2024年第2期76-82,共7页
将欧拉-欧拉(E-E)双流体模型、颗粒动力学理论(KTGF)与k-ε湍流模型耦合,以搅拌速度、固相体积分数为变量探究对釜体内液相速率、液相湍流动能的影响.结果表明:釜体内的液相速率、湍流动能与搅拌速度成正相关,且与固相体积分数的大小成... 将欧拉-欧拉(E-E)双流体模型、颗粒动力学理论(KTGF)与k-ε湍流模型耦合,以搅拌速度、固相体积分数为变量探究对釜体内液相速率、液相湍流动能的影响.结果表明:釜体内的液相速率、湍流动能与搅拌速度成正相关,且与固相体积分数的大小成负相关.当固体体积分数为2.5%、7%、13%,对应液相速度下降幅度为8%,16.2%,18.4%,对应湍动能下降幅度为7.6%,13.2%,20.6%. 展开更多
关键词 -液相 CFD 计算流体力学 颗粒动力学理论
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Study on Surface Properties for Non-polar Fluids with Density Functional Theory
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作者 吴畏 陆九芳 +2 位作者 付东 刘金晨 李以圭 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第2期256-262,共7页
The density functional theory, simplified by the local density approximation and mean-field approxi-mation, is applied to study the surface properties of pure non-polar fluids. A reasonable long rang correction is ado... The density functional theory, simplified by the local density approximation and mean-field approxi-mation, is applied to study the surface properties of pure non-polar fluids. A reasonable long rang correction is adopted to avoid the truncation of the potential. The perturbation theory is applied to establish the equation for the phase equilibrium, in which the hard-core chain fluid is as the reference fluid and the Yukawa potential is used as the perturbation term. Three parameters, ε/κ, d and ms, are regressed frorn the vapor-liquid equilibria, and the surface properties, including density profile, surface tension and local surface tension profile are predicted with these parameters. 展开更多
关键词 density functional theory surface tension density profile pure non-polar fluids
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Numerical and statistical approach for Casson-Maxwell nanofluid flow with Cattaneo-Christov theory
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作者 T.MUSHTAQ A.RAUF +3 位作者 S.A.SHEHZAD F.MUSTAFA M.HANIF Z.ABBAS 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第7期1063-1076,共14页
The rheological features of an incompressible axi-symmetric Casson-Maxwell nanofluid flow between two stationary disks are examined.The lower permeable disk is located at z=-a,while the upper disk is placed at z=a.Bot... The rheological features of an incompressible axi-symmetric Casson-Maxwell nanofluid flow between two stationary disks are examined.The lower permeable disk is located at z=-a,while the upper disk is placed at z=a.Both the disks are porous and subjected to uniform injection.The fluid properties such as thermal conductivity vary with temperature.The Cattaneo-Christov thermal expression is implemented along with the Buongiorno nanofluid theory.By operating the similarity functions,the reduced form of the fluid model in terms of ordinary differential equations is obtained and solved by the bvp4 c numerical technique.The physical quantities are demonstrated graphically on the velocity and temperature fields.Three-dimensional flow arrangements and twodimensional contour patterns against several dimensionless variables are also sketched.The numerical values of the local Nusselt and Sherwood numbers for various quantities are presented in tabular set-up.The intensity of the linear relationship between the Nusselt and Sherwood numbers is assessed through Pearson’s product-moment correlation technique.The statistical implication of the linear association between variables is also examined by the t-test statistic approach. 展开更多
关键词 Casson-Maxwell fluid porous disk Buongiorno theory variable thermal conductivity Cattaneo-Christov model uniform injection
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Bianchi Type-II, VIII &IX Perfect Fluid Cosmological Models in Brans Dicke Theory of Gravitation
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作者 Velagapudi Uma Maheswara Rao Mandangi Vijaya Santhi 《Journal of Modern Physics》 2011年第10期1222-1228,共7页
Field equations in the presence of perfect fluid distribution are obtained in a scalar tensor theory of gravitation proposed by Brans and Dicke[1] with the aid of Bianchi type-II, VIII & IX metrics. Exact prefect ... Field equations in the presence of perfect fluid distribution are obtained in a scalar tensor theory of gravitation proposed by Brans and Dicke[1] with the aid of Bianchi type-II, VIII & IX metrics. Exact prefect fluid Bianchi type- IX cosmological model is presented since other models doesn’t exist in Brans-Dicke scalar tensor theory of gravitation. Some physical properties of the model are also discussed. 展开更多
关键词 Bianchi TYPE-II VIII & IX Brans Dicke SCALAR Tensor theory Perfect fluid Distribution
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Viscous fluid damping in a laterally oscillating finger of a comb-drive micro-resonator based on micro-polar fluid theory
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作者 Sahra Azma Ghader Rezazadeh +1 位作者 Rasoul Shabani Elnaz Alizadeh-Haghighi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第3期397-405,共9页
Viscous damping is a dominant source of energy dissipation in laterally oscillating micro-structures. In microresonators in which the characteristic dimensions are comparable to the dimensions of the fluid molecules, ... Viscous damping is a dominant source of energy dissipation in laterally oscillating micro-structures. In microresonators in which the characteristic dimensions are comparable to the dimensions of the fluid molecules, the assumption of the continuum fluid theory is no longer justified and the use of micro-polar fluid theory is indispensable. In this paper a mathematical model was presented in order to predict the viscous fluid damping in a laterally oscillating finger of a micro-resonator considering micro-polar fluid theory. The coupled governing partial differential equations of motion for the vibration of the finger and the micro-polar fluid field have been derived. Considering spin and no-spin boundary conditions, the related shape functions for the fluid field were presented. The obtained governing differential equations with time varying boundary conditions have been transformed to an enhanced form with homogenous boundary conditions and have been discretized using a Galerkin-based reduced order model. The effects of physical properties of the micro-polar fluid and geometrical parameters of the oscillating structure on the damping ratio of the system have been investigated. 展开更多
关键词 Micro-electro-mechanical systems(MEMS) Micro-resonator Micro-polar theory Viscous fluid damping Galerkin method
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Investigation of intense sheet electron beam transport using the macroscopic cold-fluid model and the single-particle orbit theory
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作者 韩莹 阮存军 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期207-213,共7页
The focusing and the stable transport of an intense elliptic sheet electron beam in a uniform magnetic field are investigated thoroughly by using the macroscopic cold-fluid model and the single-particle orbit theory.T... The focusing and the stable transport of an intense elliptic sheet electron beam in a uniform magnetic field are investigated thoroughly by using the macroscopic cold-fluid model and the single-particle orbit theory.The results indicate that the envelopes and the tilted angles of the sheet electron beam obtained by the two theories are consistent.The single-particle orbit theory is more accurate due to its treatment of the space-charge fields in a rectangular drift tube.The macroscopic cold-fluid model describes the collective transport process in order to provide detailed information about the beam dynamics,such as beam shape,density,and velocity profile.The tilt of the elliptic sheet beam in a uniform magnetic field is carefully studied and demonstrated.The results presented in this paper provide two complete theories for systemically discussing the transport of the sheet beam and are useful for understanding and guiding the practical engineering design of electron optics systems in high power vacuum electronic devices. 展开更多
关键词 focusing and transport macroscopic cold-fluid model sheet electron beam single-particle orbit theory
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Experimental study of low-damage drilling fluid to minimize waterblocking of low-permeability gas reservoirs 被引量:4
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作者 Zhang Hongxia Yan Jienian +2 位作者 Lu Yu Shu Yong Zhao Shengying 《Petroleum Science》 SCIE CAS CSCD 2009年第3期271-276,共6页
This paper discusses the systematic design and development of low-damage drilling fluid to protect the low-permeability gas reservoir of the Sulige block in the Ordos Basin, Inner Mongolia Autonomous Region, China. Ba... This paper discusses the systematic design and development of low-damage drilling fluid to protect the low-permeability gas reservoir of the Sulige block in the Ordos Basin, Inner Mongolia Autonomous Region, China. Based on investigation of the geological characteristics and the potential formation damage of the Permian formation of the reservoir, waterblocking due to invasion of drilling or completion fluids was identified one of the most severe causes of damage to gas well deliverability. By adopting the phase trap prevention method, ideal packing theory, and film-forming technology, a lowdamage drilling fluid, sodium formate brine containing efficient waterblocking preventing surfactants, optimized temporary bridging agents (TBAs), and film-forming agents has been developed. The performance of the new drilling fluid was evaluated by using a variety of techniques. The results show that the fluid has good rheological properties, good strong shale-swelling inhibition, good temporary plugging effect, ultra-low filtration, and good lubricity. It can efficiently minimize waterblocking and can be used to drill horizontal wells with minimal intervention of the reservoir in the Sulige Gas Field. 展开更多
关键词 Low-permeability gas reservoir waterblocking ideal packing theory (IPT) film-forming agent drilling fluid
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A revised Cattaneo-Christov micropolar viscoelastic nanofluid model with combined porosity and magnetic effects 被引量:5
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作者 S.A.SHEHZAD S.U.KHAN +1 位作者 Z.ABBAS A.RAUF 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第3期521-532,共12页
The dynamics of non-Newtonian fluids along with nanoparticles is quite interesting with numerous industrial applications. The current predominately predictive modeling deals with the flow of the viscoelastic micropola... The dynamics of non-Newtonian fluids along with nanoparticles is quite interesting with numerous industrial applications. The current predominately predictive modeling deals with the flow of the viscoelastic micropolar fluid in the presence of nanoparticles. A progressive amendment in the heat and concentration equations is made by exploiting the Cattaneo-Christov(C-C) heat and mass flux expressions. Besides, the thermal radiation effects are contributed in the energy equation and aspect of the radiation parameter, and the Prandtl number is specified by the one-parameter approach.The formulated expressions are converted to the dimensionless forms by relevant similarity functions. The analytical solutions to these expressions have been erected by the homotopy analysis method. The variations in physical quantities, including the velocity,the temperature, the effective local Nusselt number, the concentration of nanoparticles,and the local Sherwood number, have been observed under the influence of emerging parameters. The results have shown good accuracy compared with those of the existing literature. 展开更多
关键词 micropolar viscoelastic fluid nanoparticle thermal radiation Cattaneo-Christov(C-C)theory porous medium
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Rheological property of low-damage,ideal packing,film-forming amphoteric/sulfonation polymer drilling fluids 被引量:2
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作者 张洪霞 鄢捷年 +1 位作者 舒勇 赵胜英 《Journal of Central South University》 SCIE EI CAS 2008年第S1期429-433,共5页
Low-permeability dense reservoirs,including micro-fractured reservoirs,are commonly characterized by high content of clay substances,high original water saturation,high sensitivity to invasive fluids,high capillary pr... Low-permeability dense reservoirs,including micro-fractured reservoirs,are commonly characterized by high content of clay substances,high original water saturation,high sensitivity to invasive fluids,high capillary pressure,complicated structure and anisotropic,high flow-resistance and micro pore throats etc,.Generally they also have lots of natural micro fractures,probably leading to stress sensibility.Main damaging factors in such reservoirs are water-sensibility and water-blocking caused by invasive fluids during drilling and production operations.Once damaged,formation permeability can rarely recovered.Numerous studies have shown that damaging extent of water-blocking ranges from 70% to 90%.Main damaging mechanisms and influencing factors of water-blocking were systematically analyzed.Also some feasible precaution or treating approaches of water-blocking were put forward.In a laboratory setting,a new multi-functional drilling fluid composed mainly of amphion polymer,sulfonation polymer,high effectively preventive water-blocking surfactants,ideal packing temporary bridging agents(TBA) and film-forming agents,etc.,were developed.New low-damage drilling fluids has many advantages,such as good rheological properties,excellent effectiveness of water-blocking prevention,good temporary plugging effect,low filtration and ultra-low permeability(API filtration≤5 mL,HTHP filtration≤10 mL,mud cake frictional coefficient≤0.14,permeability recovery>81%),can efficiently prevent or minimize damage,preserve natural formation and enhance comprehensive development-investment effect in TUHA Jurassic dense sandstone reservoir formation with low-permeability,the only one developing integrated condense gas field.Some references can be provided to similar reservoir formations. 展开更多
关键词 low-permeability dense gas condense reservoir AMPHION and SULFONATION polymer drilling fluid DAMAGE controlling water-blocking ideal packing theory(IPT) film-forming agent rheological properties
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Pressure Gradient Force,Saffman Lift,and Magnus Lift on the Fiber-like Particle in Fluid 被引量:5
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作者 朱泽飞 林建忠 《Journal of China Textile University(English Edition)》 EI CAS 2000年第2期23-27,共5页
Flher-like particle suspensions are common in both na-ture and industry, but there is little work reported on it.The forces acting on the fiber - like particle in fluid arestudied in this paper, and the Magnus lift, S... Flher-like particle suspensions are common in both na-ture and industry, but there is little work reported on it.The forces acting on the fiber - like particle in fluid arestudied in this paper, and the Magnus lift, Saffman lift,pressure gradient force, and then the dynamics modelhave been received. The numerical study of the simpleshear flow past the cylinders shows that the particles ’motion is controlled by the vortex. 展开更多
关键词 multi - phase fluid FIBER - LIKE PARTICLE FORCE analysis
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Oblique Water Wave Scattering by Bottom Undulation in a Two-layer Fluid Flowing Through a Channel 被引量:4
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作者 Smrutiranjan Mohapatra Swaroop Nandan Bora 《Journal of Marine Science and Application》 2012年第3期276-285,共10页
The problem of oblique wave (internal wave) propagation over a small deformation in a channel flow consisting of two layers was considered. The upper fluid was assumed to be bounded above by a rigid lid, which is an... The problem of oblique wave (internal wave) propagation over a small deformation in a channel flow consisting of two layers was considered. The upper fluid was assumed to be bounded above by a rigid lid, which is an approximation for the free surface, and the lower one was bounded below by an impermeable bottom surface having a small deformation; the channel was unbounded in the horizontal directions. Assuming irrotational motion, the perturbation technique was employed to calculate the first-order corrections of the velocity potential in the two fluids by using Green's integral theorem suitably with the introduction of appropriate Green's functions. Those functions help in calculating the reflection and transmission coefficients in terms of integrals involving the shape ftmction c(x) representing the bottom deformation. Three-dimensional linear water wave theory was utilized for formulating the relevant boundary value problem. Two special examples of bottom deformation were considered to validate the results. Consideration of a patch of sinusoidal ripples (having the same wave number) shows that the reflection coefficient is an oscillatory function of the ratio of twice the x-component of the wave number to the ripple wave number. When this ratio approaches one, the theory predicts a resonant interaction between the bed and the interface, and the reflection coefficient becomes a multiple of the number of ripples. High reflection of incident wave energy occurs if this number is large. Similar results were observed for a patch of sinusoidal ripples having different wave numbers. It was also observed that for small angles of incidence, the reflected energy is greater compared to other angles of incidence up to π/ 4. These theoretical observations are supported by graphical results. 展开更多
关键词 two-layer fluid oblique waves wave scattering reflection coefficient transmission coefficient linear water wave theory perturbation technique Bottom Undulation
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Symmetries of boundary layer equations of power-law fluids of second grade 被引量:1
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作者 Mehmet Pakdemirli Yi■it Aksoy +1 位作者 Muhammet Yürüsoy Chaudry Masood Khalique 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第6期661-670,共10页
A modified power-law fluid of second grade is considered. The model is a combination of power-law and second grade fluid in which the fluid may exhibit normal stresses, shear thinning or shear thickening behaviors. Th... A modified power-law fluid of second grade is considered. The model is a combination of power-law and second grade fluid in which the fluid may exhibit normal stresses, shear thinning or shear thickening behaviors. The equations of motion are derived for two dimensional incompressible flows, and from which the boundary layer equations are derived. Symmetries of the boundary layer equations are found by using Lie group theory, and then group classification with respect to power-law index is performed. By using one of the symmetries, namely the scaling symmetry, the partial differential system is transformed into an ordinary differential system, which is numerically integrated under the classical boundary layer conditions. Effects of power-law index and second grade coefficient on the boundary layers are shown and solutions are contrasted with the usual second grade fluid solutions. 展开更多
关键词 Power-law fluid of second grade Boundarylayers Lie group theory
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Designing Drill-in Fluids by Using Ideal Packing Technique 被引量:1
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作者 Feng Wenqiang Yan Jienian 《Petroleum Science》 SCIE CAS CSCD 2007年第2期44-51,共8页
Selecting bridging agents properly is a critical factor in designing non-damaging or low-damaging drill-in fluids. Historically, Abrams' rule has been used for this purpose. However, Abrams' rule only addresses the ... Selecting bridging agents properly is a critical factor in designing non-damaging or low-damaging drill-in fluids. Historically, Abrams' rule has been used for this purpose. However, Abrams' rule only addresses the size of particle required to initiate a bridge. The rule does not give an optimum size nor an ideal packing sequence for minimizing fluid invasion and optimizing sealing. This paper elaborates an ideal packing approach to solving the sealing problem by sealing pores with different sizes, especially those large pores which usually make dominant contribution to permeability and thereby effectively preventing the solids and filtrate of drill-in fluids from invading into formations, compared with the conventionally used techniques. Practical software has been developed to optimize the blending proportion of several bridging agents, so as to achieve ideal packing effectiveness. The method and its use in selecting the best blending proportion of several bridging agents are also discussed in this paper. A carefully designed drill-in fluid by using the ideal packing technique (named the IPT fluid) for offshore drilling operations at the Weizhou Oilfield, Nanhai West Company, CNOOC is presented. The near 100% return permeabilities from the dynamic damage tests using reservoir cores demonstrated the excellent bridging effect provided by this drill-in fluid. 展开更多
关键词 Drill-in fluid particle size distribution ideal packing theory dynamic damage test formation damage control
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