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Magnetohydrodynamic Conjugate Free Convective Heat Transfer Analysis of an Isothermal Horizontal Circular Cylinder with Temperature Dependent Viscosity
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作者 NHM. A. Azim 《Journal of Applied Mathematics and Physics》 2024年第10期3384-3401,共18页
Heat transfers due to MHD-conjugate free convection from the isothermal horizontal circular cylinder while viscosity is a function of temperature is investigated. The governing equations of the flow and connected boun... Heat transfers due to MHD-conjugate free convection from the isothermal horizontal circular cylinder while viscosity is a function of temperature is investigated. The governing equations of the flow and connected boundary conditions are made dimensionless using a set of non-dimensional parameters. The governing equations are solved numerically using the finite difference method. Numerical results are obtained for various values of viscosity variation parameter, Prandtl number, magnetic parameter, and conjugate conduction parameter for the velocity and the temperature within the boundary layer as well as the skin friction coefficients and heat transfer rate along the surface. 展开更多
关键词 Conjugate Free Convection Horizontal Circular cylinder Implicit Finite Difference Method MHD temperature Dependent Viscosity
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Effects of pouring temperature and cylinder temperature on microstructures and mechanical properties of rheomoulding AZ91D alloy 被引量:2
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作者 祁明凡 康永林 +3 位作者 周冰 朱国明 张欢欢 李扬德 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第9期2884-2892,共9页
An advanced rheomoulder,which is a device in the integration of melting metal,storage,slurry preparation,transportation and injection forming,was introduced and used to manufacture rheomoulding AZ91 D alloy.Effects of... An advanced rheomoulder,which is a device in the integration of melting metal,storage,slurry preparation,transportation and injection forming,was introduced and used to manufacture rheomoulding AZ91 D alloy.Effects of pouring temperature and cylinder temperature on microstructures and mechanical properties of rheomoulding AZ91 D alloy were investigated.The results show that the process can obtain such rheomoulding AZ91 D in which primary α-Mg particles are fine,spherical and uniformly distributed in the matrix.With the decrease of pouring temperature,the morphology of primary α-Mg particles changes from coarse rosette-like to fine spherical shape gradually.As the cylinder temperature decreases,the average size of primary α-Mg particles decreases firstly and then substantially maintains stable while the sphericity and solid fraction increase continuously.Also,decreasing pouring temperature or cylinder temperature properly contributes to improving mechanical properties of rheomoulding AZ91 D for the refinement of α-Mg particles and the decrease of porosity fraction.Furthermore,rheomoulding AZ91 D performs much better than thixomoulding,rheo-diecasting and high pressure die-casting(HPDC) in terms of mechanical properties.Compared with HPDC,the tensile strength,yield strength and elongation are increased by 27.8%,15.7% and 121%,respectively. 展开更多
关键词 AZ91D alloy rheomoulding pouring temperature cylinder temperature mechanical properties
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Experimental Study on Wear Performance and Oil Film Characteristics of Surface Textured Cylinder Liner in Marine Diesel Engine 被引量:6
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作者 Zhi-Wei Guo Cheng-Qing Yuan +1 位作者 Xiu-Qin Bai Xin-Ping Yan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第3期158-167,共10页
It is of a vital importance to reduce the frictional losses in marine diesel engines. Advanced surface textures have provided an e ective solution to friction performance of rubbing pairs due to the rapid development ... It is of a vital importance to reduce the frictional losses in marine diesel engines. Advanced surface textures have provided an e ective solution to friction performance of rubbing pairs due to the rapid development of surface engineering techniques. However,the mechanisms through which textured patterns and texturing methods prove beneficial remains unclear. To address this issue,the tribological system of the cylinder liner?piston ring(CLPR) is investigated in this work. Two types of surface textures(Micro concave,Micro V?groove) are processed on the cylinder specimen using di erent processing methods. Comparative study on the friction coe cients,worn surface texture features and oil film characteristics are performed. The results demonstrate that the processing method of surface texture a ect the performance of the CLPR pairs under the specific testing conditions. In addition the micro V?groove processed by CNCPM is more favorable for improving the wear performances at the low load,while the micro?con?cave processed by CE is more favorable for improving the wear performances at the high load. These findings are in helping to understand the e ect of surface texture on wear performance of CLPR. 展开更多
关键词 cylinder liner?piston ring(CLPR) Surface texture structure Frictional and wear characteristic Oil film characteristic
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Tribological Properties of the Plating Chromic Layer for 38CrMoAl Cylinder Liner 被引量:2
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作者 李坤 SU Tiexiong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第6期1128-1132,共5页
A chromium layer about 100 μm thickness was plated on the 38CrMoAl cylinder liner and the chromium layer was mcro quilting milled by using quilting grinding machine. The tribological properties and wear comparison te... A chromium layer about 100 μm thickness was plated on the 38CrMoAl cylinder liner and the chromium layer was mcro quilting milled by using quilting grinding machine. The tribological properties and wear comparison test were studied. The friction coefficient of the cylinder liner plated chromic layer and micro quilting milled is 15%-30% lower than the ordinary cylinder liner. The pits generated by micro quilting milling on the chromic layer surface had good effect of accommodating the abrasive grains and storaging lubricants, which improved the effect of the friction pair significantly. The single-cylinder machine run-in tests revealed that the cylinder liner with plated chromic layer and micro quilting milling had good wear durability, and was different wear mechanisms to ordinary cylinder liner. 展开更多
关键词 chrome-plated wear resistance 38CrMoAl cylinder liner
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Piston-ring and Cylinder-liner Lubrication in Internal Combustion Engines Based on Thermo-hydrodynamic 被引量:2
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作者 ZHANG Junhong GAO Hongge NI Guangjian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第6期971-975,共5页
Currently the extruded effect,roughness to the lubricant shear thinning,temperature changes and other factors or some combination of a single factor mainly considered in the lubrication study of piston ring-cylinder.I... Currently the extruded effect,roughness to the lubricant shear thinning,temperature changes and other factors or some combination of a single factor mainly considered in the lubrication study of piston ring-cylinder.In the study of the energy equation,the oil viscosity-temperature properties,adsorption layer characteristics are usually not considered.So the theoretical research is different from the actual situation of engineering.The lubrication of piston ring-cylinder liner system in internal combustion(IC) engines is studied here based on the theory of thermal flow.An unsteady and compressible hydrodynamic lubrication model with an equivalent viscosity based on shear and extruded flow factor is derived by employing the viscosity-temperature relationship,meanwhile,characteristics such as lubricating oil’s density varying with pressure and temperature,thickness of adsorbent layer and oil film’s geometry are also considered in this model.While setting up the energy equation,the effect of lubricating oil’s volume expansion and viscous dissipation on temperature,the heat conduction along oil film’s thickness direction are considered.Finite difference equation is formed by using a first-order difference scheme in time scale and second-order difference scheme in space scale.A common diesel engine is introduced as an instance to predict the distribution of the minimum oil film thickness in the piston ring-cylinder liner system.The results of simulation calculation show that the minimum oil film thickness will decrease especially around the top dead center when the oil’s volume expansion,viscous dissipation and heat conduction are considered,which implies that:it is essential to take the thermal flow idea into account during investigating piston ring-cylinder liner system’s lubrication.A more complete piston ring-cylinder liner lubrication theory was established according to thermal fluids from the perspective of research.It is more helpful to guide the practical application of engineering to improve the accuracy of forecasting the minimum film thickness.On the other hand,distribution of the minimum oil film thickness shows a nonlinear property if the thickness of piston rings and cylinder liner adsorbent layer are involved in the analysis.It may be feasible to increase the minimum oil film thickness by varying surface roughness and material properties of piston rings and cylinder liner. 展开更多
关键词 thermal flow piston ring-cylinder liner adsorbent layer viscosity-temperature revision
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Numerical analysis of temperature rise within 70MPa composite hydrogen vehicle cylinder during fast refueling 被引量:1
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作者 王亮 郑传祥 +2 位作者 李蓉 陈冰冰 魏宗新 《Journal of Central South University》 SCIE EI CAS 2014年第7期2772-2778,共7页
The numerical simulation model for predicting fast filling process of 70 MPa type Ⅲ(with metal liner) hydrogen vehicle cylinder was presented,which has considered turbulence,real gas effect and solid heat transfer is... The numerical simulation model for predicting fast filling process of 70 MPa type Ⅲ(with metal liner) hydrogen vehicle cylinder was presented,which has considered turbulence,real gas effect and solid heat transfer issues.Through the numerical analysis method,the temperature distributions of the gas within the solid walls were revealed; adiabatic filling was studied to evaluate the heat dissipation during the filling; the influences of various filling conditions on temperature rise were analyzed in detail.Finally,cold filling was proposed to evaluate the effect on temperature rise and SoC(state of charge) within the cylinder.The hydrogen pre-cooling was proved to be an effective solution to reduce maximum temperature and acquire higher SoC during the filling process. 展开更多
关键词 fast filling numerical analysis temperature rise hydrogen vehicle cylinder state of charge
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New Mg_2Si based Alloy for Automobile Engine Cylinder Liner
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作者 张道文 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第4期797-800,共4页
New Mg2Si based alloy were prepared by mechanical alloying. Sintering temperature was from 825 to 865K, which indicated that few Mg2Si were produced at lower temperature while MgO were produced at higher temperature. ... New Mg2Si based alloy were prepared by mechanical alloying. Sintering temperature was from 825 to 865K, which indicated that few Mg2Si were produced at lower temperature while MgO were produced at higher temperature. Microstructure image showed that at sintering temperature of 855K, Mg2Si were mostly synthesized with the reaction of purity magnesia powder and silicon powder. Hardness and wear tests proved that the new synthetic silicon magnesium alloy had higher hardness and good wear resistance. Under the same testing conditions, it is found that the hardness of the new material is 420.50, and pure magnesium is only 41.65.In the same experiments it is also found that under the same pressure, pure magnesium alloys than silicon wearing capacity of pure magnesium is 2 times as high that of Mg2Si based alloy. It shows that Mg2Si based alloy is the ideal material for the wear parts of car engine cylinder liner because of its small density, stable dimension, high hardness and wear-resisting. 展开更多
关键词 cylinder liner Mg2Si based alloy HARDNESS wear-resisting
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Numerical analysis on three dimensional temperature field of the gap between piston and cylinder
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作者 苑士华 王智慧 彭增雄 《Journal of Beijing Institute of Technology》 EI CAS 2013年第2期158-162,共5页
The three dimensional temperature field of the gap between piston and cylinder was ob- tained by numerically solving energy equation. The boundary condition of the equation was given in the form of heat transfer coeff... The three dimensional temperature field of the gap between piston and cylinder was ob- tained by numerically solving energy equation. The boundary condition of the equation was given in the form of heat transfer coefficient, instead of solving the temperature field of solid parts. The tem- perature field was calculated both under high speed high pressure condition and low speed low pres- sure condition. The numerical result was compared to experimental result under low speed low pres- sure condition and showed good agreement. It was shown that the influence of heat transfer coeffi- cient on t'tim temperature was significant. The adiabatic condition was reasonable under low speed low pressure condition, but invalid under high speed high pressure condition. It was a good way to describe the influence of solid parts on temperature using heat transfer coefficient but avoiding sol- ving the temperature field of solids parts. 展开更多
关键词 piston and cylinder temperature field heat transfer coefficient
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Welding temperature field analysis for featheredged cylinder based upon conformal transformation
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作者 张国栋 张富巨 《China Welding》 EI CAS 2006年第4期34-38,共5页
The accurate calculation and measurement of welding temperature field is an important precondition for welding metallurgical analysis and welding process controlling. In this paper, the conformal transformation is fir... The accurate calculation and measurement of welding temperature field is an important precondition for welding metallurgical analysis and welding process controlling. In this paper, the conformal transformation is firstly used to analyze the welding temperature field of featheredged cylinder. The center of the cylinder is chosen as the origin of column coordinate system, and every point may be expressed as complex field vector. The branch isogonality counterchanges the line parallel with the fusion line in half-infinite z-plane to the circle concentric with the fusion line in infinite cylinder. The Laplace equation and Poisson's equation still keep validity, so the temperature field equation can be solved. The conformal transformation and equation solution is processed by Matlab program language. It shows that the obtained analytical modeling of temperature field for featheredged cylinder based on conformal transformation is effective and accurate. 展开更多
关键词 welding temperature field conformal transformation cylinder thermal cycle
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SIMULATED MATHEMATICAL MODEL FOR HIGH PRESSURE CYLINDER WALL TEMPERATURE OF HOMEMADE TURBINE
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作者 Shi Xiaoping Zhu Yin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期442-445,共4页
In order to balance the contradiction between the demand of high precision and that of short time interval of model computing for the power plant simulator, a set of simulated mathematical models are constructed. The ... In order to balance the contradiction between the demand of high precision and that of short time interval of model computing for the power plant simulator, a set of simulated mathematical models are constructed. The model describes the cylinder wall temperature located at four key positions of the high pressure cylinder. The simulated model is confirmed to be not only simple but also precise via comparison between the simulated results and the autoptic data of a power plant. 展开更多
关键词 Turbine cylinder wall temperature Mathematical model Simulation
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Finite deformation swelling of a temperature-sensitive hydrogel cylinder under combined extension-torsion
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作者 M.SHOJAEIFARD M.BAGHANI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第3期409-424,共16页
The swelling behavior of a temperature-sensitive poly-N-isopropylacrylamide(PNIPAM) hydrogel circular cylinder is studied subjected to combined extension-torsion and varied temperature. In this regard, a semi-analytic... The swelling behavior of a temperature-sensitive poly-N-isopropylacrylamide(PNIPAM) hydrogel circular cylinder is studied subjected to combined extension-torsion and varied temperature. In this regard, a semi-analytical solution is proposed for general combined loading. A finite element(FE) analysis is conducted, subjecting a hydrogel cylinder to the combined extension-torsion and the varied temperature to evaluate the validity and accuracy of the solution. A user-defined UHYPER subroutine is developed and verified under free and constrained swelling conditions. The FE results illustrate excellent agreement with the semi-analytical solution. Due to the complexity of the problem, some compositions and applied loading factors are analyzed. It is revealed that for larger cross-linked density and larger ending temperature, the cylinder yields higher stresses and smaller radial swelling deformation. Besides, the radial and hoop stresses increase by applying larger twist and axial stretch. The hoop stresses intersect at approximately R/Rout = 0.58, where the hoop stress vanishes. Besides, the axial force has direct and inverse relationships with the axial stretch and the twist, respectively. However, the resultant torsional moment behavior is complex, and the position of the maximum point varies significantly by altering the axial stretch and the twist. 展开更多
关键词 extension-torsion of the circular cylinder temperature variation finite element(FE)analysis temperature-sensitive poly-N-isopropylacrylamide(PNIPAM)hydrogel semi-analytical solution
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Piston-Cylinder高温高压实验装置及在壳幔动力学研究中的应用 被引量:6
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作者 刘强 金振民 《地质科技情报》 CAS CSCD 北大核心 2006年第5期8-14,共7页
介绍了目前在国际壳幔作用及动力学研究中普遍使用的Piston-Cylinder高温高压实验技术的主要工作原理、结构、样品装置设计及主要技术指标。通过分析Piston-Cylinder高温高压实验技术在大洋和大陆板块俯冲深部过程的流体活动、基性岩石... 介绍了目前在国际壳幔作用及动力学研究中普遍使用的Piston-Cylinder高温高压实验技术的主要工作原理、结构、样品装置设计及主要技术指标。通过分析Piston-Cylinder高温高压实验技术在大洋和大陆板块俯冲深部过程的流体活动、基性岩石部分熔融作用、岩浆活动机制及约束条件等壳幔相互作用研究中的应用实例,认为引进该项实验技术对于我国科技工作者开展高温高压条件下壳幔动力学研究以及缩短我国实验岩石学技术手段与国际间的差距具有重要意义。 展开更多
关键词 Piston-cylinder 高温高压实验 壳幔动力学
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Effect of temperature on tribofilm growth and the lubrication of the piston ring-cylinder liner system in two-stroke marine engines
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作者 Xiuyi LYU Jiang HU +5 位作者 Yunchuan WANG Jinlu SHENG Xuan MA Tongyang LI Chang GE Xiqun LU 《Friction》 SCIE EI CAS CSCD 2024年第8期1858-1881,共24页
This study is an optimized extension based on the authors’previous research on the tribo-chemical reaction under constant temperature field of two-stroke internal combustion engines(ICEs).It establishes a coupled ana... This study is an optimized extension based on the authors’previous research on the tribo-chemical reaction under constant temperature field of two-stroke internal combustion engines(ICEs).It establishes a coupled analysis model that considers the tribo-chemical reactions,dynamic contact,and interface lubrication of the piston ring-cylinder liner(PRCL)system under transient temperature conditions.In this study,for the first time,the prediction of the tribofilm thickness and its influence on the surface micro-topography(the comprehensive roughness)are coupled in the working temperature field of the PRCL system,forming an effective model framework and providing a model basis and analytical basis for subsequent research.This study findings reveal that by incorporating temperature and tribofilm into the simulation model,the average friction deviation throughout the stroke decreases from 8.92%to 0.93%when compared to experimental results.Moreover,the deviation during the combustion regime reduces from 39.56%to 7.34%.The proposed coupled model provides a valuable tool for the evaluation of lubrication performance of the PRCL system and supports the analysis software forward design in two-stroke ICEs. 展开更多
关键词 TRIBOFILM piston ring-cylinder liner(PRCL)system temperature comprehensive roughness two-stroke internal combustion engines(ICEs)
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Research on testing method of resin sand high temperature compressive strength 被引量:7
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作者 Peng Wan Luan-cai Li +1 位作者 Long Zhang Wen-qing Wang 《China Foundry》 SCIE 2016年第5期335-341,共7页
High temperature compressive strength is one of the most important performances of resin sand; its value directly concerns the quality of castings. In order to seek the best testing method of resin sand high temperatu... High temperature compressive strength is one of the most important performances of resin sand; its value directly concerns the quality of castings. In order to seek the best testing method of resin sand high temperature compressive strength, a self-developed instrument was used to carry out experiments, and the sample shape and size were designed and studied. The results show that a hollow cylinder sample can reflect the strength difference of different resin sands better than a solid cylinder sample, and its data is stable. The experiments selected φ20/5×30 mm as the size of the hollow cylinder samples. The high temperature compressive strengths of phenol-formaldehyde resin coated sand, furan resin self-setting sand, and TEA resin sand were each tested. For the resin sand used for cast steel and cast iron, 1,000 ℃ was selected as the test temperature; for the resin sand used for cast non-ferrous alloy, 800 ℃ was selected as the test temperature; and for all the resin sand samples, 1 min was selected as the holding time. This testing method can truthfully reflect the high temperature performance of three kinds of resin sand; it is reproducible, and the variation coefficients of test values are under 10%. 展开更多
关键词 resin sand high temperature compressive strength hollow cylinder specimens variation coefficient
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Application and analysis of functionally graded piezoelectrical rotating cylinder as mechanical sensor subjected to pressure and thermal loads 被引量:4
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作者 G.H.RAHIMI M.AREFI M.J.KHOSHGOFTAR 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第8期997-1008,共12页
The exact thermoelastic analysis of a functionally graded piezoelectrical (FGP) rotating cylinder is investigated analytically. The cylinder is subjected to a com- bination of electrical, thermal, and mechanical loa... The exact thermoelastic analysis of a functionally graded piezoelectrical (FGP) rotating cylinder is investigated analytically. The cylinder is subjected to a com- bination of electrical, thermal, and mechanical loads simultaneously. The structure is a simplified model of a rotational sensor or actuator. The basic governing differential equation of the system is obtained by using the energy method. A novel term, named as the additional energy, is introduced to exact the evaluation of the energy functional. The solution to the governing differential equation is presented for two types of boundary conditions including free rotating and rotating cylinders exposed to the inner pressure. The effect of the angular velocity is investigated on the radial distribution of various components. The mentioned structure can be considered as a sensor for measuring the angular velocity of the cylinder subjected to the pressure and temperature. The obtained results indicate that the electrical potential is proportional to the angular velocity. 展开更多
关键词 functionally graded piezoelectric (FGP) material SENSOR rotating cylinder angular velocity PRESSURE temperature
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Atmospheric Ice Accretion on Non-Rotating Vertical Circular Cylinder
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作者 Muhammad S. Virk Umair N. Mughal Geanette Polanco 《World Journal of Engineering and Technology》 2015年第3期284-289,共6页
Study of atmospheric ice accretion on a non-rotating vertical circular cylindrical object was carried out at dry and wet ice conditions. Both numerical and experimental techniques were used during this study. 3D numer... Study of atmospheric ice accretion on a non-rotating vertical circular cylindrical object was carried out at dry and wet ice conditions. Both numerical and experimental techniques were used during this study. 3D numerical study was carried out using computational fluid dynamics based approach, whereas experimental study was carried out at Cryospheric Environmental Simulator ‘CES’ in Shinjo, Japan. A good agreement was found between experimental and numerical results. The dimensions of the cylindrical object used to measure the atmospheric ice load on structures along this study, were selected as per the ISO12494 standard. Results provide useful information about ice growth and intensity along circular cylindrical objects at different atmospheric temperatures. This research work also provides a useful base for further investigation of atmospheric ice accretion on structures particularly circular power network cables, & tower masts installed in the cold regions. 展开更多
关键词 ATMOSPHERIC ICE CIRCULAR cylinder temperature CFD Experiment
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Challenges and Methods to Improve Well Cementing Quality for 177.8 mm Liner in Gaoshiti-Moxi Area
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作者 Bin Li Jianhua Guo +2 位作者 Quan Cao Chi Chen Lin Hu 《Journal of Power and Energy Engineering》 2018年第9期1-8,共8页
Gaoshiti-Moxi structure belt of An-Yue Sinian gas reservoir, which was China’s largest monomer Marine carbonate gas reservoir up to now, located in vying-dragon female temple structure group that belong to the ancien... Gaoshiti-Moxi structure belt of An-Yue Sinian gas reservoir, which was China’s largest monomer Marine carbonate gas reservoir up to now, located in vying-dragon female temple structure group that belong to the ancient uplift slope of the middle of Sichuan. With the exploration and development of high temperature and high pressure carbonate reservoir, a large number of challenges and problems, such as long isolation section, active oil-gas show, large temperature difference, prone to super retarding cement slurry and gas channeling at flare position, have been encountered in the cementing of 177.8 mm hang-liner. In order to solve these problems, numerous measures and methods have been put into use for reducing the safety risk of cementing and improving cementing quality. The large temperature difference channeling cement slurry system, effective anti-pollution spacer and high-pressure packer type liner hanger were developed and applied for field tests in the early stage of development. In addition, equilibrium pressure cementing technology, optimizing of centralizer placement and plasma column structure, improvement of pump displacement and hold pressure while waiting on cement were used to ensure nice displacement efficiency and cementing quality. As Moxi X well for example, the cementing quality factor of merit was 40.29% and the qualification rate was up to 78.87% after adopting the cementing measures and methods above. The cementing quality was much higher than previous level and provided technical support for Gaoshiti-Moxi area. 展开更多
关键词 GM Area liner CEMENTING Long Isolation Section Large temperature Difference Anti-Intrude Cement SLURRY
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基于改进EEMD-MB1DCNN的船用柴油机缸套-活塞环故障诊断 被引量:2
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作者 王永坚 范金宇 +2 位作者 蔡杭溪 赵凯 吴怡婷 《船海工程》 北大核心 2024年第1期30-35,共6页
针对船用中高速柴油机缸套-活塞环振动信号非线性非平稳性以及同类型不同损伤程度故障发生时振动信号时频域特征相似、故障难以识别等问题,利用振动信号辨识故障,提出一种基于改进集成经验模态分解方法和多模块一维卷积神经网络端到端缸... 针对船用中高速柴油机缸套-活塞环振动信号非线性非平稳性以及同类型不同损伤程度故障发生时振动信号时频域特征相似、故障难以识别等问题,利用振动信号辨识故障,提出一种基于改进集成经验模态分解方法和多模块一维卷积神经网络端到端缸套-活塞环故障诊断方法,通过设计固有模态分量IMF信息质量筛选准则对EEMD分解出的IMFs进行重新排序,获得包含更多凸显故障特征成分的重构信号,输入到上述神经网络模型,通过振动信号分析并与现有方法比较,评估所设计IMF信息质量筛选准则与所搭建模型的性能,试验结果显示该方法能准确、有效地识别缸套-活塞环故障类型。在判断该易损件同类型不同磨损程度故障诊断中有较高的准确率,能对故障状况进行有效的特征提取与故障分类。 展开更多
关键词 船用柴油机 缸套与活塞环 EEMD 1DCNN 故障诊断
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Study on Oil Cavity Number of Hydrostatic Guide Sleeve of Electro-hydraulic Servo Cylinder
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作者 SHAO Junpeng XU Longfei SUN Guitao 《International Journal of Plant Engineering and Management》 2019年第4期219-230,共12页
The electro-hydraulic servo drive hydraulic cylinder has many unique advantages, such as fast response, high load stiffness, high control power, strong anti-eccentric load ability and so on, so it has been widely used... The electro-hydraulic servo drive hydraulic cylinder has many unique advantages, such as fast response, high load stiffness, high control power, strong anti-eccentric load ability and so on, so it has been widely used in industrial control. Based on the guide sleeve of hydrostatic seal of hydraulic cylinder, the reasonable number of oil chamber of guide sleeve is studied in this paper. ICEM CFD software and FLUENT simulation software are used to calculate and analyze the number of different oil chambers of guide sleeve of hydrostatic seal. The temperature field of piston rod with different moving speed, different initial pressure of oil chamber and oil film under different number of oil chambers is analyzed. The relationship between the pressure field and temperature field provides a better basis for optimizing the design of hydrostatic guide sleeve and helps to improve the servo drive cylinder. 展开更多
关键词 electro-hydraulic servo hydraulic cylinder hydrostatic seal guide sleeve number of oil chambers pressure field temperature field
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THE NUMERICAL ANALYSIS OF UNSTEADY HEAT TRANSFER OF A PISTON-LINER COUPLED SYSTEM IN AN INTERNAL COMBUSTION ENGINE
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作者 蒋惠强 《Journal of Southeast University(English Edition)》 EI CAS 1993年第2期69-78,共10页
This paper provides a numerical analysis model of unsteady heat trans-fer in piston-liner set of an internal combustion engine.The model simulates the un-steady heat transfer process among the combustion mixture,pisto... This paper provides a numerical analysis model of unsteady heat trans-fer in piston-liner set of an internal combustion engine.The model simulates the un-steady heat transfer process among the combustion mixture,piston set,lubricantfilm,liner and coolant in a whole engine cycle,and can predict the temperature fluc-tuation and distribution on piston crown,inner surface of liner,piston ring and thelubricant film.A computer program is developed to calculate the unsteady heat trans-fer process of piston-liner system in a water-cooled diesel engine. 展开更多
关键词 FEM FDM I.C. Engine temperature distributions transients fluctuation/unsteady heat transfer piston-liner coupled system
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