期刊：
Applied Mechanics and Materials,2014年543-547:164-167 ISSN：1660-9336
作者机构：
[Yu, Nan Hui] School of Mechanical Engineering, Wuhan Polytechnic University, Wuhan, 430023, China;[Fan, Ji Jun] School of Electrical and Electronic Engineering, Wuhan Polytechnic University, Wuhan, 430023, China
会议名称：
International Conference on Vehicle and Mechanical Engineering and Information Technology, VMEIT 2014
会议时间：
19 February 2014 through 20 February 2014
关键词：
Finite element method;Press cage;Screw press;Stress analysis
期刊：
Applied Mechanics and Materials,2014年530-531:911-914 ISSN：1662-7482
作者机构：
[Yu, Nan Hui; Li, Shi Long; Liu, De Wen] School of Mechanical Engineering, Wuhan Polytechnic University, Wuhan, 430023, China
关键词：
Finite element analysis;Pressing screw;Screw press
摘要：
Screw pressing technology provides a pressing process superior to those traditional ones. Screw press has been used in oil extraction with a long history, both for cold and hot pressing of vegetable oil materials. Pressing screw is the core component of screw press, as a very important working part, its strength is a precondition for ensuring normal operation of the whole machine. Considering the complexity and drawbacks of conventional analysis and check methods for pressing screw, a simplified three-dimensional model of which was set up, then finite element analysis was done, thus obtaining its continuous deformation and stress distribution with the results close to those from theoretical calculation. Hence, this method can be applied to rapidly and correctly find those dangerous positions and existing imperfections of its structure, thus providing valuable data to judge its structural rationality before practical manufacture, so as to make further improvements and optimizations for its structural design.
摘要：
Owing to the excellent tensile strength and corrosion-resistance of fiber reinforced unsaturated polyester composite, it is expected to solve the corrosion problem of building instead of steel bars in some special occasions. Bonding performance between concrete and FRP rebars was studied by pull-out test,the influences of the surface form, anchorage length and diameter of FRP rebar on bonding strength were discussed in detail.
摘要：
The internal structure of magnetorheological fluid could change under external magnetic field, as well as its dielectric constant and magnetic conductance. A theoretical model of electromagnetic wave propagation in MRF was established and the basic formula of transmissivity was deduced. Theoretical simulation shows that the electromagnetic wave transmissivity decreases with the increasing of dielectric constant of magnetorheological fluid, and increases with the magnetic permeability. Theoretical analysis indicates that the change of its structure and dielectric magnetic properties of MR fluids is the main cause for the fact that the transmittance could be adjusted under external magnetic field.
期刊：
Telkomnika (Telecommunication Computing Electronics and Control),2013年11(2):689-693 ISSN：1693-6930
通讯作者：
Yu, N.(nanhui_yu@hotmail.com)
作者机构：
[Nanhui Yu] School of Mechanical Engineering, Wuhan Polytechnic University, Wuhan, China;[Jijun Fan] School of Electric and Electronic Engineering, Wuhan Polytechnic University, Wuhan, China
摘要：
Electrorheological fluids(ER fluid) as an electrically controllable acoustic medium has been proved by experimental studies. In this paper,the sound attenuation in ER fluid at different propagation distances was experimentally studied. The results show that sound attenuation of ER fluid could be adjusted by the particle concentration of ER fluid and the intensity of electric field. Amplitude of sound wave in ER fluid increases with the increasing of particle concentration and field intensity; on the other hand, the attenuation of sound wave decreases with the increasing of propagation distance, as well as the particle concentration and field intensity. The experimental results indicate that the solidification effect of ER fluid is beneficial to the propagation of sound wave. \nDOI: http://dx.doi.org/10.11591/telkomnika.v11i2.1994
作者机构：
[Yu N.] School of Mechanical Engineering, Wuhan Polytechnic University, Wuhan, Hubei, 430023, China;[Fan J.] School of Electric and Electronic Engineering, Wuhan Polytechnic University, Wuhan, Hubei, 430023, China
通讯机构：
[Yu, N.] S;School of Mechanical Engineering, , Wuhan, Hubei, 430023, China
会议名称：
2013 2nd International Conference on Manufacture Engineering,Quality and Production System(ICMEQP 2013)
摘要：
In this paper, the dielectric constants of ER fluids with different particle concentration were measured by frequency method, and their electrical conductivities under different external electrical fi
会议名称：
2nd International Conference on Materials and Products Manufacturing Technology (ICMPMT 2012)
会议时间：
SEP 22-23, 2012
会议地点：
Guangzhou, PEOPLES R CHINA
会议主办单位：
[Yu, Nanhui] Wuhan Polytech Univ, Sch Mech Engn, Wuhan 430023, Hubei, Peoples R China.^[Fan, Jijun] Wuhan Polytechn Univ, School Elect & Elect Engn, Wuhan, Hunan, Peoples R China.
会议论文集名称：
Advanced Materials Research
关键词：
Amplitude;Attenuation of acoustic wave;ER fluid
摘要：
The attenuation behavior of acoustic wave in ER fluid which was made by mixing starch in silicon oil was studied through experiments. The results demonstrate that the particle concentration of fluid and the intensity of extra electric field have certain influences on the attenuation behavior of acoustic wave passing through ER fluid. When othe conditions are fixed, the amplitude of acoustic wave passing through ER fluid increases along with the increasing of particle concentration or field intensity; meanwhile, the acoustic wave presents attenuation with the increasing of distance measured, and its trend slows down when the concentration or field intensity increases. The analysis indicates that the solidification effect of ER fluid caused by extra electric field may be the reason for these phenomena.
摘要：
The sound attenuation in ER fluid was experimentally studied. The results show that sound attenuation of ER fluid could be adjusted by the particle concentration of ER fluid and the intensity of electric field. Amplitude of sound wave in ER fluid increases with the increasing of particle concentration and field intensity; on the other hand, the attenuation of sound wave decreases with the increasing of propagation distance, as well as the particle concentration and field intensity. The experimental results indicate that the solidification effect of ER fluid is beneficial to the propagation of sound wave.
关键词：
Carbonyl iron powder;Magnetorheological fluids;Microwave reflectivity
摘要：
In this paper, experimental study of the microwave reflection behavior in MRF was carried out. The results showed that at the same frequency the microwave reflectivity of MRF decreased with the increasing of magnetic field strength; and with the increasing of particle concentration, microwave reflectivity decreased, monotonously. Under the given magnetic field, with the increasing of microwave frequency, it first decreased, there is a lowest point at 9.2GHz, and then it increased. Usually, it is considered that the change of internal structure of MRF under external magnetic field is the main reason for the regulation behavior of microwave reflectivity.
作者机构：
[范吉军; Zhai C.-W.] School of Electric and Electronic Engineering, Wuhan Polytechnic University, Wuhan 430023, China;[余南辉] School of Mechanical Engineering, Wuhan Polytechnic University, Wuhan 430023, China
通讯机构：
[Fan, J.-J.] S;School of Electric and Electronic Engineering, Wuhan Polytechnic University, China
关键词：
电流变液;淀粉颗粒;速度测量;激光散斑
摘要：
利用激光散斑测量装置，观察悬浮在电流变液中的淀粉颗粒在外加直流电场下的运动情况，表明当激光穿过电流变液时可以形成散斑。利用激光散斑测速法(LSV)对不同外加电场强度和不同浓度的淀粉电流变液中颗粒的运动速度进行了测量，通过自编的互相关计算软件对散斑图像进行了分析，获得了淀粉颗粒沿电场方向和垂直于电场方向的运动速度。实验结果表明在同一电场作用下，淀粉颗粒运动速度随时间的变化呈现震荡递减的趋势；并且存在一个临界颗粒浓度和临界电场强度，当低于此临界值时，颗粒运动速度增加，反之则减小。 The velocities of particles in Electrorheological (ER) fluids were measured by laser speckle velocimetry. It was verified that laser speckles could be formed by illuminating laser beam on the starch ER fluids. The speckle patterns was recorded with high speed CCD camera, and the speckle patterns sequences with short time intervals was obtained by intercepting laser speckle video. Velocities parallel to the direction of electric field and that perpendicular to the direction of electric field were obtained by processing the two consecutive speckle patterns. The experimental results show that the velocities of particles decreases oscillatorily with time. Furthermore, there is a critical electric field and a critical sample concentration. When it is lower than this critical electric field (particle concentration), the mean particle velocity increases; otherwise, it decreased.
摘要：
Owing to its unique properties and wide engineering applications, magnetorheological fluids (MRF) has become a hot study area in the field of smart materials. In this paper experimental study of the microwave reflection behavior in MRF was carried out. The results indicated that at the same frequency the microwave reflectivity of MRF decreased with the increasing of magnetic field strength; and with the particle concentration increasing, microwave reflectivity first increased, then decreased, there is a critical concentration of 15%. Under the same magnetic field, with the increasing of microwave frequency, it first decreased, there is a lowest point at 9.2GHz, and then it increased. Usually, it is considered that the change of internal structure of MRF under external magnetic field is the main reason for the regulation behavior of microwave reflectivity.
期刊：
Journal of Physics: Conference Series,2011年276(1):1-8 ISSN：1742-6588
通讯作者：
Fan Jijun
作者机构：
[Fan Jijun; Zhai Chaowu; Du Zhenfei] Wuhan Polytech Univ, Dept Math & Phys, Wuhan 430023, Peoples R China.;[Yu Nanhui] Wuhan Polytech Univ, Coll Mech Engn, Wuhan 430023, Peoples R China.
通讯机构：
[Fan Jijun] W;Wuhan Polytech Univ, Dept Math & Phys, Wuhan 430023, Peoples R China.
会议名称：
3rd International Photonics & OptoElectronics Meetings(第三届国际光子与光电子学会议 POEM 2010)
会议时间：
2010-11-03
会议地点：
武汉
会议主办单位：
[Fan Jijun;Zhai Chaowu;Du Zhenfei] Wuhan Polytech Univ, Dept Math & Phys, Wuhan 430023, Peoples R China.^[Yu Nanhui] Wuhan Polytech Univ, Coll Mech Engn, Wuhan 430023, Peoples R China.
会议论文集名称：
3rd International Photonics & OptoElectronics Meetings(第三届国际光子与光电子学会议 POEM 2010)论文集
关键词：
ER fluids;velocity measurement;laser speckle;dielectric particles
摘要：
Usually, it is regarded that the movement of dielectric particles in ER fluids is related to the generation of electrorheological effect. In this paper, the principle of measuring infinitesimal displacement by laser speckle is proposed to measure the velocities of particles in ER fluids. It is verified that speckles can be formed by illuminating laser beam on the starch ER fluids. The speckle patterns was recorded with high speed CCD camera, and the speckle patterns sequences with short time intervals was obtained by intercepting laser speckle video. Displacements parallel to electric field and perpendicular to electric field were obtained by processing the two consecutive speckle patterns. The experimental results showed the velocities of particles exhibit the trend towards an oscillatory decreased with time, and a critical electric field and a critical sample concentration exist, when lower than this critical electric field (concentration), the mean particle velocity tends to increase; when high than that, decrease instead. Moreover, the horizontal velocity of particle is almost zero, there is only small oscillatory movement of particles in the vertical direction of electric field when the particle chain of ER fluid forms a relatively stable structure.
