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Lattice Boltzmann Method for Conduction and Radiation Heat Transfer in Composite Materials

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Journal of Thermal Science 2022年第3期31卷 777-789页

作者： TONG Zixiang LI Mingjia XIE Tao GU Zhaolin School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an710049China School of Energy&Power Engineering Xi’an Jiaotong UniversityKey Laboratory of Thermo-Fluid Science and Engineering of Ministry of EducationXi’an710049China Institute of Industrial Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an710049China

In this work,the utilization of lattice Boltzmann method(LBM)in the simulation of coupled conduction and radiation heat transfer in composite materials is studied.The novel D3Q30-LBM and D3Q38-LBM models are proposed for the simulation of radiative transfer equation(RTE).The LBM-LBM model,coupled finite volume method(FVM)and LBM are compared with the coupled FVM and discrete ordinate method(DOM)for 2D and 3D simulations.The results show that the original D3Q26-LBM is insufficient for the simulation of radiation,and both the D3Q30-LBM and D3Q38-LBM are close to the DOM for the RTE.The LBM can have large errors in the simulation of heat conduction when the relaxation time is large.Thus,its application in the composite materials is limited when the ratio between thermal conductivities of different components is large.The models with LBM for RTE can be more efficient than the FVM-DOM for the simulation of conduction-radiation heat transfer in composite materials.The FVM-D3Q30-LBM model is suggested because of its accuracy and efficiency.

关键词： lattice Boltzmann method conduction-radiation heat transfer discrete directions composite material discrete ordinate method

Enhancing anoxic denitrification of low C/N ratio wastewater with novel ZVI composite carriers

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Journal of Environmental Sciences 2022年第2期34卷 180-191页

作者： Yanping Shi tao Liu Hongtao Yu xie Quan Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China

External organic carbon sources are needed to provide electron donors for the denitrification of wastewater with a low COD/NO_(3)^(-)-N(C/N)ratio,increasing the treatment cost.The economic strategy is to enhance the bioactivity and/or biodiversity of denitrifiers to efficiently utilize organic substances in wastewater.In this study,novel zero-valent iron(ZVI)composite carriers were prepared and implemented in a suspended carrier biofilm reactor to enhance the bioactivity and/or biodiversity of denitrifiers.At the influent C/N ratio of 4(COD was 179.5±5.0 mg/L and TN was 44.2±0.8 mg/L),COD and TN removal efficiencies were 85.1%and 66.4%,respectively,in the reactors filled with 3 wt%ZVI composite carriers.In contrast,COD and TN removal efficiencies were 70.4%and 55.3%,respectively,in the reactor filled with conventional high-density polyethylene(HDPE)biofilm carriers.The biofilm formation on the 3 wt%ZVI composite carriers was optimized due to its higher roughness(surface square roughness increased from 76.0 nm to 93.8 nm)and favorable hydrophilicity(water contact angle dropped to 72.5°±1.4°from 94.3°±3.2°)compared with the HDPE biofilm carriers.In addition,heterotrophic denitrifiers,Thauera and Dechloromonas,were enriched,whereas autotrophic denitrifiers,Raoultella and Thiobacillus,exhibited high relative abundance in the biofilm of ZVI composite carriers.The coexistence of heterotrophic denitrifiers and autotrophic denitrifiers on the surface of ZVI composite carriers provided mixotrophic metabolism of denitrification(including heterotrophic and iron-based autotrophic),thereby ensuring effective denitrification for wastewater with a low C/N ratio without external organic carbon source addition.

关键词： ZVI Biofilm carrier Low C/N ratio Integrated floating fixed-film and activated sludge(IFFAS) Denitrification

Exact solution of the two-mode quantum Rabi model

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Communications in Theoretical Physics 2020年第6期72卷 57-64页

作者： Qiong-tao xie College of Physics and Electronic Engineering Hainan Normal UniversityHaikou 571158China

An analytical method is developed to study the two-mode quantum Rabi model.For certain specific parameter conditions,especially for the resonant conditions,we obtain an infinite number of the exact solutions of the eigenfunctions and associated energies.It is shown that there exist new types of the exact energies which do not correspond to the level-crossings.Our analytical method may find applications in some related models.

关键词： exact solutions two-mode quantum Rabi model level-crossings

Real-time localization for underwater equipment using an extremely low frequency electric field

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Defence Technology（防务技术） 2023年第8期26卷 203-212页

作者： Jia-wei Zhang Peng Yu Run-xiang Jiang tao-tao xie College of Weapon Engineering Naval University of EngineeringWuhan430033China Weaponry Department Naval Petty Officer AcademyBengbu233012China College of Electric Engineering Naval University of EngineeringWuhan430033China

A new real-time underwater equipment location method adopting an electric field induced by a standard current source is proposed.Our goals were real-time tracking and location of stationary or moving underwater equipment both in shallow and deep seas,under noisy conditions.The main features of this method are as follows:(1)a standard current source on the water surface,which can be towed by a vehicle,consisting of two electrodes,a signal generator,and a GPS unit;(2)measurement of the extremely low frequency(ELF)electric field emitted by the current source,made possible by electric field sensors on the underwater equipment;(3)position of the underwater equipment is estimated in real time based on a progressive update extended Kalman filter(PUEKF),which is carried out using the propagation model of an ELF electric field because the electric field at the position of the underwater equipment and the current source position are known.We verified the accuracy of our method and confirmed real-time location feasibility through numerical,physical scale,and real-time sea experiments.Through numerical experiments,we verified that our method works for underwater equipment location in real-world conditions,and the location error can be less than 0.2 m.Next,real-time location experiments for stationary underwater measuring equipment in water tank were conducted.The result shows that the location error can be less than 0.1 m.We also confirmed real-time location feasibility through the use of offshore experiment.We expect that our method will complement conventional underwater acoustic location methods for underwater equipment in acoustically noisy environments.

关键词： Termsd Real-time tracking and location method Underwater equipment location ELF electric field Shallow sea Physical scale experiment Sea experiment

Generalized Christoffel Functions for Power Orthogonal Polynomials

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Acta Mathematicae Applicatae Sinica 2014年第3期30卷 819-832页

作者： XIE Tao Yan LIANG Guangdong Country Garden School College of Mathematics and Computer Science Key Laboratory of High Performance Computing and Stochastic Information Processing(HPCSIP)(Ministry of Education of China)Hunan Normal University

In this paper we extend the Christoffel functions to the case of power orthogonal polynomials.The existence and uniqueness as well as some properties are given.

关键词： generalized Christoffel function existence uniqueness gaussian quadrature formula Christoffel number

Telomerase-mediated immortalization of human vaginal wall fibroblasts derived from patients with pelvic organ prolapse

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Chinese Medical Journal 2023年第5期136卷 578-587页

作者： tao Guo Ting xie Jinghe Lang Zhijing Sun Department of Obstetrics and Gynecology Peking Union Medical College HospitalPeking Union Medical CollegeChinese Academy of Medical SciencesNational Clinical Research Center for Obstetric&Gynecologic DiseasesBeijing 100730China Department of Medical Research Center Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China.

Background: Extracellular matrix (ECM) remodeling is the most important pathomechanism of pelvic organ prolapse (POP). Fibroblasts are the key to ECM regulation. The passaging capacity of human vaginal wall fibroblasts (hVWFs) is limited in vitro . Here, we aimed to immortalize hVWFs through the introduction of human telomerase reverse transcriptase (hTERT). Methods: Primary cells were derived from the vaginal wall tissue of patients with POP. Cellular senescence was detected via senescence-associated β-galactosidase staining. We employed a lentiviral transfection vector to stably express hTERT in hVWFs at passage 3, generating immortalized hVWFs (i-hVWFs). We then assessed cellular proliferation via the CCK-8 and EdU assays as well as cellular migration via wound healing assays. G-banded chromosome karyotypic analysis was performed to evaluate chromosomal karyotype stability. Finally, cellular tumorigenesis capacity was assessed in nude mice. A two-tailed Student’s t test was used to compare differences between the two groups. Results: Our results showed that senescence of primary hVWFs significantly increased from passage seven. From passage 11, hVWFs showed a significantly higher senescence percentage than i-hVWFs. During the continuous passage, i-hVWFs presented stability in proliferation, migration capacity, expression of ECM regulation-related genes, and chromosome karyotype. In vivo tumorigenesis was absent in i-hVWFs. Conclusions: The senescence of hVWFs significantly increased from the seventh passage, and we successfully used hTERT to immortalize hVWFs derived from patients with POP. Studies on POP that require a long-lived hVWF line will benefit from our technique.

关键词： Pelvic organ prolapse Fibroblasts Telomere shortening Cellular senescence

Investigation on the stability and anti-eccentric load margin of a novel structure bearing lubricated by low viscosity medium

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Science China(Technological Sciences) 2022年第7期65卷 1613-1633页

作者： xie ZhongLiang JIAO Jian YANG Kang HE tao Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China School of Mechanical-Electric Engineering Xidian UniversityXi'an 710071China Wuhan Second Ship Design and Research Institute Wuhan 430205China

The paper studies the anti-eccentric load margin of a novel structure bearing lubricated by low viscosity medium. The lubrication dynamic model considering journal inclination angle is established. The effects of different speeds, loads, and tilted angles on the interface attributes of the bearing under typical working conditions are studied. The results show that the special structure bearing has self-stability margin of anti-tilted and anti-eccentric load. Particularly under different speed conditions, analyses show that the eccentric load has little influence on the static/dynamic characteristics of the bearing. Under the same conditions, the stability margin of the bearing is higher than that of traditional bearings. The research provides a theoretical basis for the application of such kinds of special structure bearings.

关键词： water-lubricated bearing tilted angle anti-eccentric load margin lubrication performance

Investigation of the effect of filling level on the wear and vibration of a SAG mill by DEM

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Particuology 2022年第4期20卷 24-34页

作者： Changhua xie Yuan Zhao tao Song Yongzhi Zhao Institute of Process Equipment Zhejiang UniversityHangzhou 310027China State Key Laboratory of Process Automation in Mining & Metallurgy.Beijing 100160 China Beijing Key Laboratory of Process Automation in Mining & Metallurgy Beijing 100160China

Semi-autogenous grinding(SAG)mill is widely used in the grinding process of coal and ores because of its strong applicability,large capacity and low consumption of grinding media.Therefore,the research of SAG mill is still of great important practical significance.Among those parameters of the SAG mill,the flling level is very important for it is not only directly related to the processing capacity of the mill,but also affects the operation cost and stability of mill.In this paper,combined with shear impact energy model(SIEM)and discrete element method(DEM),the particle collision energy spectrum was applied to analyze the influence of ore flling level and media flling level on the power draw of the mill,the impact energy on ore,and the wear of liner and media in a slice of an industrial SAG mill.It was found that increasing the ore flling level would increase energy consumption and reduce the energy efficiency and the wear of liner and grinding media.Furthermore,the vibration of mill was explored from the collision energy on liner.The results showed that the low frequency but high energy ollision between grinding media and liner was the main reason for liner wear and mill vibration.

关键词： Flling level SAG mill Collision energy DEM Wear Vibration

A virtual test and evaluation method for fully mechanized mining production system with diferent smart levels

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International Journal of Coal Science & Technology 2022年第3期9卷 151-170页

作者： Jiacheng xie Fuxiang Ge tao Cui Xuewen Wang Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment Taiyuan University of TechnologyNo.216 mailboxHuYu CampusNo.18XinKuangYuan RoadTaiyuan 030024ShanxiChina Post-Doctoral Research Workstation of Taiyuan Mining Machinery Group Co. LtdTaiyuan 030032China

A smart fully mechanized coal mining working face is comprised of various heterogeneous equipment that work together in unknown coal seam environments.The goal is to form a smart operational system with comprehensive perception,decisionmaking,and control.This involves many work points and complex coupling relationships,indicating it needs to be performed in stages and coordinated to address key problems in all directions and along multiple points.However,there are no existing unifed test or analysis tools.Therefore,this study proposed a virtual test and evaluation method for a fully mechanized mining production system with diferent smart levels.This is based on the concept of“real data processing–virtual scene construction–setting key information points–virtual operation and evaluation.”The actual operational data for a specifc working face geology and equipment were reasonably transformed into a visual virtual scene through a movement relationship model.The virtual operations and mining conditions of the working face were accurately reproduced.Based on the sensor and execution error analyses for diferent smart levels,the input interface for sensing,decision-making,and control was established for each piece of equipment,and an operation evaluation system was constructed.The system comprehensively simulates and tests the key points of sensing decision-making and control with various smart levels.The experimental results showed that the virtual scene constructed based on actual operational data has a high simulation degree.Users can simulate,analyze,and evaluate the overall operations of the smart mining 2.0–4.0 working face by inputting key information.The future direction for the smart development of fully mechanized mining is highlighted.

关键词： Smart mining Mining robot Digital twin Virtual simulation Test and evaluation