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Lattice Boltzmann simulations of high-order statistics in isotropic turbulent flows

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Applied Mathematics and Mechanics(English Edition) 2018年第1期39卷 21-30页

作者： Guodong JIN shizhao wang Yun wang Guowei HE Stake Key Laboratory of Nonlinear Mechanics (LNM) Institute of MechanicsChinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

The lattice Boltzmann method （LBM） is coupled with the multiple-relaxation- time （MRT） collision model and the three-dimensional 19-discrete-velocity （D3Q19） model to resolve intermittent behaviors on small scales in isotropic turbulent flows. The high- order scaling exponents of the velocity structure functions, the probability distribution functions of Lagrangian accelerations, and the local energy dissipation rates are investi- gated. The self-similarity of the space-time velocity structure functions is explored using the extended self-similarity （ESS） method, which was originally developed for velocity spatial structure functions. The scaling exponents of spatial structure functions at up to ten orders are consistent with the experimental measurements and theoretical results, implying that the LBM can accurately resolve the intermittent behaviors. This valida~ tion provides a solid basis for using the LBM to study more complex processes that are sensitive to small scales in turbulent flows, such as the relative dispersion of pollutants and mesoscale structures of preferential concentration of heavy particles suspended in turbulent flows.

关键词： mesoscopic modelling lattice Boltzmann method (LBM) isotropic turbulent flow structure function intermittency high-order statistics self-similarity

Study on synergistic leaching of potassium and phosphorus from potassium feldspar and solid waste phosphogypsum via coupling reactions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 117-129页

作者： Chao Li shizhao wang Yunshan wang Xuebin An Gang Yang Yong Sun School of Chemical Engineering and Technology Hebei University of TechnologyTianjin 300130China National Engineering Research Center of Green Recycling for Strategic Metal Resources Chinese Academy of SciencesBeijing 100190China School of Engineering Edith Cowan University270 Joondalup DriveJoondalupWA 6027Australia Key Laboratory of Carbonaceous Wastes Processing and Process Intensification of Zhejiang Province The University of Nottingham Ningbo ChinaNingbo 315100China

To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this *** study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in *** impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this *** results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,*** study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of *** apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively.

关键词： Phosphogypsum Potassium feldspar Coupling reaction Leaching Waste treatment Kinetics

Far-field approximations to the derivatives of Green’s function for the Ffowcs Williams and Hawkings equation

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Advances in Aerodynamics 2022年第1期4卷 218-240页

作者： Zhiteng Zhou Zhenyu Zang Hongping wang shizhao wang Institute of Mechanics Chinese Academy of SciencesBeijing100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing100049China

The surface correction to the quadrupole source term of the Ffowcs Williams and Hawkings integral in the frequency domain suffers from the computation of high-order derivatives of Green’s *** far-field approximations to the derivatives of Green’s function have been used without derivation and verification in previous *** this work,we provide the detailed derivations of the far-field approximations to the derivatives of Green’s *** binomial expansions for the derivatives of Green’s function and the far-field condition are employed during the derivations to circumvent the difficulties in computing the high-order *** approximations to the derivatives of Green’s function are systemically verified by using the benchmarks two-dimensional convecting vortex and the co-rotating vortex *** addition,we provide the derivations of the approximations to the multiple integrals of Green’s function by using the far-field approximations to the derivatives.

关键词： Ffowcs Williams and Hawkings integral Green’s function High-order derivatives Far-field approximation

Simplified permeable surface correction for frequency-domain Ffowcs Williams and Hawkings integrals

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Theoretical & Applied Mechanics Letters 2021年第4期11卷 192-196页

作者： Zhiteng Zhou Hongping wang shizhao wang The State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

A simplified surface correction formulation is proposed to diminish the far-field spurious sound generated by the quadrupole source term in Ffowcs Williams and Hawkings(FW-H)*** proposed formulation utilizes the far-field asymptotics of the Green’s function to simplify the computation of its high-order derivatives,which circumvents the difficulties reported in the original frequency-domain surface correction *** proposed formulation has been validated by investigating the benchmark case of sound generated by a convecting *** results show that the proposed formulation successfully eliminates the spurious *** applications of the proposed formulation to flows with some special parameters are also discussed.

关键词： FW-H integral Surface correction Quadrupole source Aeroacoustics

Numerical Simulation of a Three-Dimensional Fish-like Body Swimming with Finlets

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Communications in Computational Physics 2012年第4期11卷 1323-1333页

作者： shizhao wang Xing Zhan Guowei He LNM Institute of MechanicsChinese Academy of SciencesBeijing 100190P.R.China

The swimming of a 3Dfish-like bodywith finlets is numerically investigated at Re=1000(the Reynolds number is based on the uniform upstream flow and the length of the fish-like body).The finlets are simply modeled as thin rigid rectangular plates that undulate with the *** wake structures and the flow around the caudal peduncle are *** finlets redirect the local flow across the caudal peduncle but the vortical structures in the wake are almost not affected by the *** of hydrodynamic performance has not been found in the simulation based on this simple *** present numerical result is in agreement with that of the work of Nauen and Lauder[***.,204(2001),pp.2251-2263]and partially supports the hypothesis ofWebb[***.,190(1975),pp.1-159].

关键词： Finlets fish swimming Immersed Boundary method wake structure

Wall-modeling for large-eddy simulation of flows around an axisymmetric body using the diffuse-interface immersed boundary method

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Applied Mathematics and Mechanics(English Edition) 2019年第3期40卷 305-320页

作者： Beiji SHI Xiaolei YANG Guodong JIN Guowei HE shizhao wang The State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences School of Engineering Sciences University of Chinese Academy of Sciences Department of Civil Engineering College of Engineering and Applied Sciences Stony Brook University

A novel method is proposed to combine the wall-modeled large-eddy simulation(LES) with the diffuse-interface direct-forcing immersed boundary(IB) *** new developments in this method include:(i) the momentum equation is integrated along the wall-normal direction to link the tangential component of the effective body force for the IB method to the wall shear stress predicted by the wall model;(ii) a set of Lagrangian points near the wall are introduced to compute the normal component of the effective body force for the IB method by reconstructing the normal component of the velocity. This novel method will be a classical direct-forcing IB method if the grid is fine enough to resolve the flow near the wall. The method is used to simulate the flows around the DARPA SUBOFF model. The results obtained are well comparable to the measured experimental data and wall-resolved LES results.

关键词： wall model large-eddy simulation(LES) immersed boundary(IB)method diffuse-interface

A new numerical framework for large-eddy simulation of waves generated by objects piercing water surface

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Theoretical & Applied Mechanics Letters 2019年第2期9卷 79-83页

作者： Zixuan Yang Zuo Cui shizhao wang The State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Sciences University of Chinese Academy of Sciences School of Aerospace Engineering Guizhou Institute of Technology

A novel numerical framework is developed for large-eddy simulation(LES) of interactions among air, water, and solid bodies. The motions of air and water are solved on a fixed block-structured mesh, with the air–water interface captured using the volume-of-fluid method. A new sub-grid scale stress model based on the vortex identifier is used to improve the robustness and efficiency of the simulation flows with air–water interface. The new framework is tested in the context of bow waves and Kelvin waves generated by a water-surface vehicle. Wave breaking at the bow of the vehicle is captured in LES. The LES results of wave geometry approaches the measurements progressively as the grid resolution is refined. The simulation results indicate that LES is a useful tool for studying wave dynamics of water-surface vehicles.

关键词： Large-eddy simulation Wave breaking Wave-structure interactions

Efficient and selective photocatalytic nitrite reduction to N_(2)through CO_(2)anion radical by eco-friendly tartaric acid activation

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Chinese Chemical Letters 2024年第11期35卷 249-253页

作者： Jingtai Bi Yupeng Cheng Mengmeng Sun Xiaofu Guo shizhao wang Yingying Zhao Engineering Research Center of Seawater Utilization of Ministry of Education School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300401China Hebei Collaborative Innovation Center of Modern Marine Chemical Technology Tianjin 300401China Tianjin Key Laboratory of Chemical Process Safety Tianjin 300130China

In this study,the environmentally friendly precursor,tartaric acid(TA),was employed for the generation of CO_(2)anion radical(CO_(2)^(·-))in an advanced UV/TA/Fe^(3+)system to reduce the hazardous NO_(2)^(-)-N in *** optimize this process,various factors,including the dosage of Fe^(3+),TA,and p H,were systematically investigated for their impact on the reduction *** the conditions of 3 mmol/L Fe^(3+)dosage,10 mmol/L TA dosage,and a pH of 2.5,NO_(2)^(-)-N was effectively removed from the water within 60 min,selectively transformed into N_(2),with a remarkable N_(2)selectivity of 91.2%.In the optimal conditions,the NO_(2)^(-)-N reduction mechanism in the UV/TA/Fe^(3+)system and the critical role of CO_(2)^(·-)were ***,this study explored the reduction of real nitrified seawater using the UV/TA/Fe^(3+)*** results demonstrated that the UV/TA/Fe^(3+)system could completely eliminate NO_(2)^(-)-N and achieve a N_(2)selectivity of up to 90%,with minimal interference from coexisting *** work holds promising implications for the environmentally benign treatment of nitrite-polluted wastewater.

关键词： Nitrite Advanced reduction processes Photocatalysis CO_(2)anion radicals Tartaric acid

Nondestructive monitoring of annealing and chemical-mechanical planarization behavior using ellipsometry and deep learning

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Microsystems & Nanoengineering 2023年第2期9卷 345-354页

作者： Qimeng Sun Dekun Yang Tianjian Liu Jianhong Liu shizhao wang Sizhou Hu Sheng Liu Yi Song The Institute of Technological Sciences Wuhan UniversityWuhanChina School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhanChina Hongyi Honor College of Wuhan University WuhanChina school of Power and Mechanical Engineering Wuhan UniversityWuhanChina The School of Microelectronics Wuhan UniversityWuhanChina

The Cu-flling process in through-silicon via(TSV-Cu)is a key technology for chip stacking and three-dimensional vertical *** this process,defects resulting from chemical-mechanical planarization(CMP)and annealing severely affect the reliability of the *** methods of defect characterization are destructive and *** this study,a new defect inspection method was developed using Mueller matrix spectroscopic ***-Cu with a 3-μm-diameter and 8-μm-deep Cu filling showed three typical types of characteristics:overdishing(defect-OD),protrusion(defect-P),and *** process dimension for each defect was 13 ***,the three typical defects caused by CMP and annealing were *** single-channel deep learning and a Mueller matrix element(MME),the TSV-Cu defect types could be distinguished with an accuracy rate of 99.94%.Next,seven effective MMEs were used as independent channels in the artificial neural network to quantify the height variation in the Cu flling in the *** accuracy rate was 98.92%after training,and the recognition accuracy reached 1 *** proposed approach rapidly and nondestructively evaluates the annealing bonding performance of CMP processes,which can improve the reliability of high-density integration.

关键词： annealing defect chemical