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Dynamic characteristics of conveyor belts

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Journal of China University of Mining and Technology 2008年第4期18卷 629-633页

作者： HOU you-fu meng Qing-mi School of Mechanical and Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221116 China

The dynamic characteristics of a belt conveyor are determined to a large extent by the properties of the belt. This paper describes experiments designed to establish the dynamic properties of belting material. The dynamic elastic modulus, viscous damping and rheologicat constants of the belt were measured. Several properties were studied as a function of the tensile loading on the belt. These included longitudinal vibration, the natural vibration frequency in the transverse direction and the response to an impulse excitation. Vibration response was observed under several different excitation frequencies. Most of these properties have not been tested previously under conditions appropriate for the ISO/DP9856 standard. Two types of belt were tested, a steel reinforced belt and a fabric reinforced belt. The test equipment was built to provide data appropriate for designing belt conveyors. It was observed that the stress wave propagation speed increased with tensile load and that tensile load was the main factor influencing longitudinal vibrations.

关键词： experimental investigation dynamic characteristics conveyor belt

Pulsed dynamic electrolysis enhanced PEMWE hydrogen production:Revealing the effects of pulsed electric fields on protons mass transport and hydrogen bubble escape

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Journal of Energy Chemistry 2025年第1期100卷 201-214页

作者： Xuewei Zhang Wei Zhou Yuming Huang Liang Xie Tonghui Li Huimin Kang Lijie Wang Yang Yu Yani Ding Junfeng Li Jiaxiang Chen Miaoting Sun Shuo Cheng Xiaoxiao meng Jihui Gao Guangbo Zhao School of Energy Science and Engineering Harbin Institute of Technology China Datang Technology Innovation Co. Ltd

The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis （PEMWE） emerging as the preeminent pathway for hydrogen *** remarkable advancements in this field,confronting the sluggish electrochemical kinetics and inherent high-energy consumption arising from deteriorated mass transport within PEMWE systems remains a formidable *** impediment stems primarily from the hindered protons mass transfer and the untimely hydrogen bubbles *** address these challenges,we harness the inherent variability of electrical energy and introduce an innovative pulsed dynamic water electrolysis *** to constant voltage electrolysis (hydrogen production rate:51.6 m L h-1,energy consumption:5.37 kWh Nm-3H2),this strategy (hydrogen production rate:66 m L h-1,energy consumption:3.83 kWh Nm-3H2) increases the hydrogen production rate by approximately 27%and reduces the energy consumption by about 28%.Furthermore,we demonstrate the practicality of this system by integrating it with an off-grid photovoltaic （PV） system designed for outdoor operation,successfully driving a hydrogen production current of up to 500 mA under an average voltage of approximately 2 *** combined results of in-situ characterization and finite element analysis reveal the performance enhancement mechanism:pulsed dynamic electrolysis （PDE） dramatically accelerates the enrichment of protons at the electrode/solution interface and facilitates the release of bubbles on the electrode *** such,PDE-enhanced PEMWE represents a synergistic advancement,concurrently enhancing both the hydrogen generation reaction and associated transport *** promising technology not only redefines the landscape of electrolysis-based hydrogen production but also holds immense potential for broadening its application across a diverse spectrum of electrocatalytic endeavors.

关键词： Electrolysis

Shape and Size Optimization of Truss Structures under Frequency Constraints Based on Hybrid Sine Cosine Firefly Algorithm

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Computer Modeling in Engineering & Sciences 2023年第1期134卷 405-428页

作者： Ran Tao Xiaomeng Yang Huanlin Zhou zeng meng School of Civil Engineering Hefei University of TechnologyHefei230009China

Shape and size optimization with frequency constraints is a highly nonlinear problem withmixed design variables,non-convex search space,and multiple local ***,a hybrid sine cosine firefly algorithm(HSCFA)is proposed to acquire more accurate solutions with less finite element *** full attraction model of firefly algorithm(FA)is analyzed,and the factors that affect its computational efficiency and accuracy are revealed.A modified FA with simplified attraction model and adaptive parameter of sine cosine algorithm(SCA)is proposed to reduce the computational complexity and enhance the convergence ***,the population is classified,and different populations are updated by modified FA and SCA ***,the random search strategy based on Lévy flight is adopted to update the stagnant or infeasible solutions to enhance the population *** selection technique is applied to save the promising solutions and further improve the convergence ***,the adaptive penalty function is employed to deal with the ***,the performance of HSCFA is demonstrated through the numerical examples with nonstructural masses and frequency *** results show that HSCFA is an efficient and competitive tool for shape and size optimization problems with frequency constraints.

关键词： Firefly algorithm sine cosine algorithm frequency constraints structural optimization

Comparison of CS,CGM and CS-CGM for Prediction of Pipe’s Inner Surface in FGMs

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Computers, Materials & Continua 2017年第4期53卷 271-290页

作者： Haolong Chen Bo Yu Huanlin Zhou zeng meng School of Civil Engineering Hefei University of TechnologyHefeiP.R.C. 不详

The cuckoo search algorithm(CS)is improved by using the conjugate gradient method(CGM),and the CS-CGM is *** unknown inner boundary shapes are generated randomly and evolved by Lévy flights and elimination mechanism in the CS and *** CS,CGM and CS-CGM are examined for the prediction of a pipe’s inner *** direct problem is two-dimensional transient heat conduction in functionally graded materials(FGMs).Firstly,the radial integration boundary element method(RIBEM)is applied to solve the direct *** the three methods are compared to identify the pipe’s inner surface with the information of measured ***,the influences of timepoints,measurement point number and random noise on the inverse results are *** is found that the three algorithms are promising and can be used to identify the pipe’s inner *** CS-CGM has higher accuracy and faster convergence speed than the CS and *** CS and CS-CGM are insensitive to the initial *** CGM and CS-CGM are more insensitive to the measurement noises compared with the *** the increase of timepoints and measurement points,and with the decrease of measurement noises,the inverse results are more accurate.

关键词： Inverse geometry problems transient heat conduction functionally graded materials Cuckoo search algorithm conjugate gradient method

A PRIORI AND A POSTERIORI ERROR ESTIMATES OF A WEAKLY OVER-PENALIZED INTERIOR PENALTY METHOD FOR NON-SELF-ADJOINT AND INDEFINITE PROBLEMS

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Journal of Computational Mathematics 2014年第3期32卷 332-347页

作者： Yuping zeng Jinru Chen Feng Wang Yanxia meng School of Mathematics Jiaying University Meizhou 513015 China Jiangsu Key Laboratory for NSLSCS School of Mathematical Sciences Nanjing Normal University Nanjing 210023 China

In this paper, we study a weakly over-penalized interior penalty method for non-self- adjoint and indefinite problems. An optimal a priori error estimate in the energy norm is derived. In addition, we introduce a residual-based a posteriori error estimator, which is proved to be both reliable and efficient in the energy norm. Some numerical testes are presented to validate our theoretical analysis.

关键词： Interior penalty method Weakly over-penalization Non-self-adjoint and indefinite A priori error estimate A posteriori error estimate.

“现代性”的路还有多长——近期中篇小说创作的一个方面

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当代文坛 2025年第1期 4-14页

作者：孟繁华沈阳师范大学中国文化与文学研究所

现代性主要是西方几个世纪前缔造的。中国为了回应西方的现代性产生了中国的现代性,它带来了巨大的希望和可能性,同时也有允诺迟迟不临的虚幻性。我们已经看到,一心向西方学习的倾向正在发生变化。就当前的创作而言,中篇小说非常注意“... 详细信息

现代性主要是西方几个世纪前缔造的。中国为了回应西方的现代性产生了中国的现代性,它带来了巨大的希望和可能性,同时也有允诺迟迟不临的虚幻性。我们已经看到,一心向西方学习的倾向正在发生变化。就当前的创作而言,中篇小说非常注意“中国性”也就是本土性的开拓和建构,呈现出多元并存、竞相开放的新格局。我们也要注意的是,西方缔造的这个“现代性”,正在把我们抛进一个越来越说不清楚的困境中,我们长久渴望的东西居然像幻觉一样虚无缥缈。质疑和反思“现代性”,重视本土性的开拓和建构,这从一个方面表达了当下文学“反现代”的现代性。这是特别值得我们注意的文学潮流或现象。

关键词：中篇小说现代性本土性幻觉性

Editorial for the Special Issue on 10th Anniversary of Friction

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Friction 2022年第10期10卷 1439-1442页

作者： Jianbin LUO Yonggang meng Zhongmin JIN Hongbo zeng State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China School of Mechanical Engineering University of LeedsLeeds LS29JTUK Chemical and Materials Engineering University of AlbertaEdmonton Alberta T6G 2R3Canada

The year 2022 marks the 10th anniversary of the founding of *** was launched on 26 March 2013,with an aim to promote the development in tribology by publishing theoretical and experimental research works as well as mo... 详细信息

关键词： friction wear founding

BASES OF BIQUADRATIC POLYNOMIAL SPLINE SPACES OVER HIERARCHICAL T-MESHES

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Journal of Computational Mathematics 2017年第1期35卷 91-120页

作者： Fang Deng Chao zeng meng Wu Jiansong Deng School of Mathematical Sciences University of Science and Technology of China Hefei China School of Mathematics Hefei University of Technology Hefei China

Basis functions of biquadratic polynomial spline spaces over hierarchical T-meshes are constructed. The basis functions are all tensor-product B-splines, which are linearly independent, nonnegative and complete. To make basis functions more efficient for geometric modeling, we also give out a new basis with the property of unit partition. Two preliminary applications are given to demonstrate that the new basis is efficient.

关键词： Spline spaces over T-meshes CVR graph Basis functions.

Enhancing mine groundwater system prediction:Full-process simulation of mining-induced spatio-temporal variations in hydraulic conductivities via modularized modeling

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International Journal of Mining Science and Technology 2024年第12期34卷 1625-1642页

作者： Shihao meng Qiang Wu Yifan zeng Leiyu Gu National Engineering Research Center of Coal Mine Water Hazard Controlling China University of Mining and Technology-BeijingBeijing 100083China National Mine Safety Administration Key Laboratory of Mine Water Hazard Controlling Beijing 100083China University of Mining and Technology(Beijing)Inner Mongolia Research Institute Inner Mongolia 017000China China Huaneng Coal Technology Research Co. Ltd.Beijing 100031China

The intricate interplay between rock mechanics and fracture-induced fluid flow during resource extrac-tion exerts profound effects on groundwater systems,posing a pivotal challenge for promoting green and safe development in underground *** address this,a novel numerical model with an explicit coupling simulation strategy is *** model integrates distinct modules for individual physical mechanisms,ensuring second-order accuracy through shared time integration,thereby overcoming lim-itations in simulating mining-induced strata damage,water flow,and permeability dynamics.A novel mathematical model is incorporated into the mechanical simulation to characterize the abrupt increase in permeability resulting from rock fracture *** increase is quantified by evaluating the plastic damage state of rocks and incorporating a damage coefficient that is intrinsically linked to rock *** mechanical model tracks permeability changes due to *** flow model simulates aquifer-mine water interactions by calculating hydraulic conductivity and using dynamic zoning,adapt-ing to mining *** applied to a case study of a complex mine,this approach significantly improved the accuracy of water inflow rate predictions by 57%.

关键词： Time-dependent permeability Overburden damage Mine water inflow Fluid-mechanical interaction Modular simulation