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Comparison of lattice and pseudo 3D numerical simulation of tip screen out operation

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Petroleum 2023年第3期9卷 454-467页

作者： Ahmed Merzoug Vibhas Pandey Vamegh Rasouli Branko Damjanac Hui Pu Department of Petroleum Engineering University of North DakotaGrand ForksNDUSA ConocoPhillips HoustonTXUSA Itasca Consulting Group MinneapolisUSA

Hydraulic fracturing(HF)is a commonly used technique to stimulate low permeability formations such as shale plays and tight ***,this method of well stimulation has also been used in high permeable unconsolidated sandstone formations to bypass near-wellbore formation damage and prevent sand production at some distance apart from the wellbore *** treatment is called frac-pack completion,where a short length but wide width fracture is formed by injecting aggressive concentrations of proppant into the fracture *** operation is known as tip screen-out(TSO).Detailed design of fluid and proppant,including an optimal pump schedule,is required to achieve satisfactory *** this study,we first assess the lattice-based numerical method's capabilities for simulating hydraulic fracturing propagation in elastoplastic *** results will be compared with the same case simulation results using a pseudo 3D(P3D)model and analytical ***,we explore the Nolte(1986)design for frac-pack and TSO treatment using lattice-based software and the P3D *** results showed that both models could simulate the hydraulic fracturing propagation in soft formation and TSO operation,while some differences were observed in generated geometry,the tip screenout time and net pressure *** results are *** was noted that fracture propagation regime(viscosity/toughness),nonlocality and nonlinearity had an influence on the different *** advantages of each model will be discussed.

关键词： Frac-pack Tip screen-out lattice Pseudo 3D Proppant Pump schedule

Properties of a multispeed lattice Boltzmann equation

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Science China Mathematics 1996年第8期39卷 876-882页

作者：刘慕仁孔令江 Department of Physics Guangxi Normal University Guilin 541001 China

A multispeed lattice Boltzmann equation with nine velocity directions on a two-dimension square lattice is investigated. In the macroscopic hydrodynamic equation, the coefficient before convective term becomes 1 and t... 详细信息

关键词： multispeed lattice Boltzmann equation Maxwell-Boltzmann distribution function viscosity.

Spatiotemporal quasiperiodicity transition to chaos in the one-way coupled bistability lattice system

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Science China Mathematics 1999年第2期42卷 213-219页

作者：杨世平田钢屈进禄徐树山 OCAST (World Laboratory) Beijing China Department of Physics Hebei Normal University Shijiazhuang China

One-way coupled optical bistability lattice (OCBL) system for open flow is investigated. By using numerical simulations spatiotemporal quasiperiodicity is found. A rough phase diagram indicating the main spatiotemporal dynamic behavior in weakly coupled lattice is given. The transitions between spatiotemporal quasiperiodicity and chaos are observed. This result is important for the understanding of turbulence.

关键词： bistability one-way coupled lattice spatiotemporal quasiperiodicity spatiotemporal chaos.

Spontaneous chiral-symmetry breaking of lattice QCD with massless dynamical quarks

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Science China(Physics,Mechanics & Astronomy) 2007年第1期50卷 6-14页

作者： LUO XiangQian Department of Physics,School of Physics and Engineering,Sun Yat-Sen University,Guangzhou 510275,China Department of Physics School of Physics and Engineering Sun Yat-Sen University Guangzhou 510275 China

One of the most challenging issues in QCD is the investigation of spontaneous chiral-symmetry breaking, which is characterized by the non-vanishing chiral condensate when the bare fermion mass is zero. In standard methods of the lattice gauge theory, one has to perform expensive simulations at multiple bare quark masses, and employ some modeled functions to extrapolate the data to the chiral limit. This paper applies the probability distribution function method to computing the chiral condensate in lattice QCD with massless dynamical quarks, without any ambiguous mass extrapolation. The results for staggered quarks indicate that this might be a promising and efficient method for investigating the spontaneous chiral-symmetry breaking in lattice QCD, which deserves further investigation.

关键词： lattice QCD spontaneous chiral-symmetry breaking dynamical quarks

Robust topology optimization of multi-material lattice structures under material and load uncertainties

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Frontiers of Mechanical Engineering 2019年第2期14卷 141-152页

作者： Yu-Chin CHAN Kohei SHINTANI Wei CHEN Department of Mechanical Engineering Northwestern UniversityEvanstonIL 60208USA

Enabled by advancements in multi-material additive manufacturing,lightweight lattice structures consisting of networks of periodic unit cells have gained popularity due to their extraordinary performance and wide array of *** work proposes a density-based robust topology optimization method for meso-or macroscale multi-material lattice structures under any combination of material and load *** method utilizes a new generalized material interpolation scheme for an arbitrary number of materials,and employs univariate dimension reduction and Gauss-type quadrature to quantify and propagate *** formulating the objective function as a weighted sum of the mean and standard deviation of compliance,the tradeoff between optimality and robustness can be studied and *** of a cantilever beam lattice structure under various material and load uncertainty cases exhibit the efficiency and flexibility of the *** accuracy of univariate dimension reduction is validated by comparing the results to the Monte Carlo approach.

关键词： robust topology optimization lattice structures multi-material material uncertainty load uncertainty univariate dimension reduction

Self-Consistent Approach for Mapping Interacting Systems in Continuous Space to lattice Models

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Chinese Physics Letters 2012年第8期29卷 81-84页

作者： WU Biao XU Yong DONG Lin SHI Jun-Ren International Center for Quantum Materials Peking UniversityBeijing 100871 Institute of Physics Chinese Academy of SciencesBeijing 100190 Department of Physics and Astronomy and Rice Quantum InstituteRice UniversityHoustonTexas 77251-1892USA

We propose a general variational principle for mapping the interacting systems in continuous space to lattice *** on the principle,we derive a set of self-consistent nonlinear equations for the Wannier functions(or,equivalently for the Bloch functions).These equations show that the Wannier functions can be strongly influenced by the interaction and be significantly different from their non-interacting *** approach is demonstrated with interacting bosons in an optical lattice,and illustrated quantitatively by a simple model of interacting bosons in a double well *** is shown that the so-determined lattice model parameters can be significantly different from their non-interacting values.

关键词： potential lattice interacting

Boron arsenide heterostructures:lattice-matched heterointerfaces and strain effects on band alignments and mobility

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npj Computational Materials 2020年第1期6卷 1636-1642页

作者： Kyle Bushick Sieun Chae Zihao Deng John T.Heron Emmanouil Kioupakis Department of Materials Science and Engineering University of MichiganAnn ArborMI 48109USA

BAs is a III–V semiconductor with ultra-high thermal conductivity,but many of its electronic properties are *** work applies predictive atomistic calculations to investigate the properties of BAs heterostructures,such as strain effects on band alignments and carrier mobility,considering BAs as both a thin film and a substrate for lattice-matched *** results show that isotropic biaxial in-plane strain decreases the band gap independent of sign or *** addition,1%biaxial tensile strain increases the in-plane electron and hole mobilities at 300 K by>60%compared to the unstrained values due to a reduction of the electron effective mass and of hole interband ***,BAs is shown to be nearly lattice-matched with InGaN and ZnSnN2,two important optoelectronic semiconductors with tunable band gaps by alloying and cation disorder,respectively.

关键词： strain alloying lattice

Thermodynamic Transitions of Antiferromagnetic Ising Model on the Fractional Multi-branched Husimi Recursive lattice

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Communications in Theoretical Physics 2014年第11期61卷 749-754页

作者：黄然陈翀 School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Rushand Ran Research Co.

The multi-branched Husimi recursive lattice is extended to a virtual structure with fractional numbers of branches joined on one site. Although the lattice is undrawable in real space, the concept is consistent with regular Husimi lattice. The Ising spins of antiferromagnetic interaction on such a set of lattices are calculated to check the critical temperatures(Tc) and ideal glass transition temperatures(Tk) variation with fractional branch numbers. Besides the similar results of two solutions representing the stable state(crystal) and metastable state(supercooled liquid)and indicating the phase transition temperatures, the phase transitions show a well-defined shift with branch number variation. Therefore the fractional branch number as a parameter can be used as an adjusting tool in constructing a recursive lattice model to describe real systems.

关键词： critical temperature ideal glass transition Ising model fractional multi-branched Husimi lattice

Verifiable Identity-Based Encryption with Keyword Search for IoT from lattice

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Computers, Materials & Continua 2021年第8期68卷 2299-2314页

作者： Lin Mei Chungen Xu Lei Xu Xiaoling Yu Cong Zuo School of Science Nanjing University of Science and TechnologyNanjing210094China College of Data Science Taiyuan University of TechnologyTaiyuan030000China Faculty of Information Technology Monash UniversityClayton3800Australia

Internet of Things(IoT),which provides the solution of connecting things and devices,has increasingly developed as vital tools to realize intelligent ***,source-limited IoT sensors outsource their data to the cloud,which arises the concerns that the transmission of IoT data is happening without appropriate consideration of the profound security challenges *** encryption technology can guarantee the confidentiality of private data,it hinders the usability of *** encryption(SE)has been proposed to achieve secure data sharing and ***,most of existing SE schemes are designed under conventional hardness assumptions and may be vulnerable to the adversary with quantum ***,the untrusted cloud server may perform an unfaithful search *** address these problems,in this paper,we propose the first verifiable identity-based keyword search(VIBKS)scheme from *** particular,a lattice-based delegation algorithm is adopted to help the data user to verify both the correctness and the integrity of the search ***,in order to reduce the communication overhead,we refer to the identity-based *** conduct rigorous proof to demonstrate that the proposed VIBKS scheme is ciphertext indistinguishable secure against the semi-honestbut-curious *** addition,we give the detailed computation and communication complexity of our VIBKS and conduct a series of experiments to validate its efficiency performance.

关键词： Internet of Things verifiable lattice searchable encryption