Journal of Jiangsu University(Natural Science Eidtion)

[an error occurred while processing this directive]

Journal of Jiangsu University(Natural Science Eidtion)

Home | About Journal | Editorial Board | Subscriptions | Instruction | Contacts Us | 中文

　

Office Online

　

　

　

　

　

　

Editor-in-chief

　

Journal Online

　

　

Forthcoming Articles

　

　

　

　

　

Download Articles

　

　

Quick Search

Advanced Search

Journal of Jiangsu University(Natural Science Eidtion)

	2018 Vol.39 Issue.2 Published 2018-03-10

	Article

Article

	125	Effect of multiparameter coupling on sec-butanol laminar burning velocity
		HAN Zhi-Qiang, QIAN Yun-Shou, TIAN Wei, XIA Qi
		The effects of atmospheric pressure, unburned mixture temperature and equivalence ratio on the secbutanolair laminar flow combustion were investigated by the smear method and the spherical flame diffusion method. The coupling effects of environmental parameters and equivalence ratio on the unstretched laminar burning propagation velocity and the change value, change rate and ratio of change rate of unstretched laminar burning propagation velocity were mainly analyzed. The results show that the larger the pressure is, the smaller the variation of unstretched laminar propagation velocity is under the coupling of ambient pressure and equivalent ratio. The ratio of change rate of unstretched laminar burning propagation velocity is increased with the increasing of equivalence ratio with downward trend for the equivalence ratio around 1.10. When the equivalence ratio is less than 1.05, the low pressure environment has greater influence on the laminar flow combustion. Under the coupling of ambient temperature and equivalence ratio, the propagation velocity of unstretched flame is more affected by higher ambient temperature when the equivalence ratio is in the range from 0.75 to 1.15. When the equivalence ratio is less than 0.85 or greater than 1.45, the equivalent ratio has great influence on the rate of nontensile laminar flow combustion.
		2018 Vol. 39 (2): 125-131 [Abstract] ( 822 ) [HTML 1KB] [ PDF 2603KB] ( 2046 )

	132	Optimum control strategy of regenerative braking energy for electric vehicle
		GUO Jin-Gang, DONG Hao-Xuan, SHENG Wei-Hui, TU Chao
		To improve the regenerative braking energy for electric vehicles, the optimal control strategy of regenerative braking energy was proposed based on braking rate control. According to the ideal regenerative braking control strategy, theoretical analysis and simulation analysis methods were used to investigated the relationship between regenerative braking energy and braking rate. The optimal braking rate was analyzed to maximize regeneration energy under various initial braking velocity by the vehicle longitudinal dynamics theory and the cosimulation model built in MATLAB/Simulink and CarSim. The variation law of optimal braking rate was fitted by the least square method to gain polynomial fitting equation. The optimum control strategy of regenerative braking energy was designed with two parts of braking force distribution and optimal braking rate control, and it was compared with the ideal regenerative braking control strategy. The results show that the braking rate has great influence on regenerative braking energy, and the optimized regeneration energy can be realized under single braking condition by the optimum control strategy.
		2018 Vol. 39 (2): 132-138 [Abstract] ( 2190 ) [HTML 1KB] [ PDF 1993KB] ( 3064 )

	139	Development of electric power steering in loop simulation test bench
		CAO Yan-Ling, CAO Zeng, XU Li-You
		To solve the problems of traditional vehicle EPS system performance test with long test period, high input cost and low efficiency, the experimental platform was redeveloped based on the TAT6/TL type of electric power steering in the loop simulation test bench. According to the working characteristics and testing requirements of EPS system, the electric push rod loading device was selected, and the electric putter realtime control was realized based on the speed and steering wheel angle by MCS912 controller. The steering resistance was accurately simulated under different steering conditions. By the virtual test technology and EPS test bench, the debugging was conveniently and quickly realized to reduce the dependence on real vehicle test. The performance of the linear EPS system was verified by the resistance test of ground and steering condition, the current follower and the response characteristic test. The results show that the simulation and test results are basically consistent, which can meet the requirements of EPS performance test.
		2018 Vol. 39 (2): 139-143 [Abstract] ( 1812 ) [HTML 1KB] [ PDF 1923KB] ( 2070 )

	144	Carbon emission analysis and evaluation of engineering refurbished tire based on life cycle
		WANG Qiang, JIAO Sheng-Jie
		The carbon emission models of engineering refurbished tire were constructed based on life cycle analysis, and the theoretic calculation model and the calculation method of carbon emission were proposed for four stages of engineering refurbished tire with production, transportation, usage and recycle. The carbon emission evaluation indexes of pure carbon surplus, carbon subduction model and carbon subduction rate of engineering refurbished tire were given, and the carbon emission lists at production, transportation and usage stages of engineering refurbished tire were quantitatively analyzed. The carbon emissionsubduction lists of five recycling stages of second refurbishment, combustion decomposition, mechanical smash, power generation by combustion and low temperature smash were analyzed, and the comparing analysis and evaluation of carbon emissions at different stages were performed. The results show that the carbon emission of engineering refurbished tire is maximal at production stage and is minimal at transporting stage. The carbon emission subduction efficiency of second retreading is the best, while those of combustion decomposition and low temperature smash are the worst.
		2018 Vol. 39 (2): 144-148 [Abstract] ( 1052 ) [HTML 1KB] [ PDF 1513KB] ( 1938 )

	149	Effects of V groove on critical heat flux of flow boiling in microchannel
		WANG Ying-Hui, ZHU Jing, SHENG Lin-Hong-Yi
		According to volume of fluid model and user defined function, the numerical simulation was performed to predict the flow boiling of water in 0.2 mm×20.0 mm microchannel with V grooves. The effects of the ratio of groove depth to width h/R and the groove number n on critical heat flux of flow boiling were analyzed. The results show that under the working conditions with inlet water temperature Tin of 369.00 K, velocity v of 0.2 m·s-1 and a certain number of grooves n of 30, the critical heat flux(CHF) in microchannels is different by varying h/R with R of 0.02 mm. Setting h/R with different values of 1, 2, 3 and 4, the critical heat fluxes are 400, 375, 500 and 450 kW·m-2, respectively, and the highest CHF is 500 kW·m-2 for h/R of 3. When h/R is given as 3, the critical heat flux is increased with the increasing of groove number. While n values are taken as 30, 90 and 150, the critical heat fluxes are 500, 525, 575 kW·m-2, respectively. Under a certain condition, suitable groove structure with h/R of 3 and much more V grooves on heating wall can improve the critical heat flux in microchannel, which is helpful to maintain the reliability of flow boiling heat transfer.
		2018 Vol. 39 (2): 149-154 [Abstract] ( 965 ) [HTML 1KB] [ PDF 2085KB] ( 1844 )

	155	Coalescence of dispersed phase droplet under uniform electric field
		WANG Zhen-Tao, ZHU Zhong-Hui, XIA Lei, ZHENG Jun, WANG Xiao-Ying, LI Rui
		To explore the influence of operation parameters on the movement and coalescence of droplets, the effects of electric field intensity, droplet size, distance and relative location between two droplets on coalescence were numerically investigated by the volumeoffluid (VOF) method to track the interface and by leaky dielectric model to simulate the electric field. The factors of electric field intensity, droplet size, droplet surface spacing and droplet relative position on the droplets coalescence were analyzed theoretically and compared with the numerical results. The results indicate that the efficiency is increased with the increasing of electric field intensity and decreased with the increasing of droplet diameter ratio, distance and relative angle between two droplets. The influence of field intensity on coalescence is complicated. When the electric field intensity is large enough, the two droplets can not produce coalescence process, and the droplet is elongated or rebounded by the other droplet. There is a critical value of electric field intensity for droplets coalescence.
		2018 Vol. 39 (2): 155-162 [Abstract] ( 986 ) [HTML 1KB] [ PDF 2387KB] ( 2056 )

	163	Effects of liquid metal physical properties on transport of selfevaporating MHD power generation system
		ZHENG Xing-Wen, LU Peng, YANG Pei-Jie, HUANG Hu-Lin
		According to the numerical simulation method, the phase change heat transfer and the gasliquid twophase flow transport of sodium metal were simulated by CFD and Fluent software. In order to obtain the effects of fluid physical parameters on twophase flow transport, the fluid physical parameters were changed successively. The results show that high density and thermal conductivity with small heat capacity of liquid metal can increase the outlet velocity of liquid metal and improve the twophase flow transport. The effect of viscosity on twophase flow is not obvious. In order to avoid annular flow in the outlet section to reduce power generation efficiency, the volume fraction of liquid metal should not be less than 20%.
		2018 Vol. 39 (2): 163-167 [Abstract] ( 1004 ) [HTML 1KB] [ PDF 2151KB] ( 1485 )

	168	Tooth profile modification and tooth contact analysis of precision forging spiral bevel gear
		YANG Jian-Jun, GONG Fei, ZHANG Hua
		To improve the contact performance of precision forging spiral bevel gear, a fully conjugated gear surface with predesigned transmission relation was established based on the pinion tooth surface model and the pinion machiningtool parameters. Taking the conjugate surface as base level, an approach was proposed to built second order easeoff surface. Based on the discrete tooth surface, the contact pattern and the transmission error curve were obtained by computational method with the critical interference judging of meshing state, and the simulation results were basically consistent with the predesigned transmission relation. The effects of second order easeoff surface parameters on the transmission error curve and contact pattern of tooth surface were also investigated. The results show that the accurate control on the length and location of the contact ellipse and the angle of the contact path can be realized by the easeoff surface parameters.
		2018 Vol. 39 (2): 168-173 [Abstract] ( 1556 ) [HTML 1KB] [ PDF 3392KB] ( 1342 )

	174	Correlation between cutting force and surface roughness based on Copula function
		PEI Hong-Jie, LI Gong-An, FU Kun-Peng, CHEN Shao-Feng, WANG Gui-Cheng
		To predict the surface roughness in machining process, the nonlinear correlation between common monitoring parameters of cutting force and surface roughness should be quantitatively described. The sample values of cutting force and the surface roughness were obtained by turning 7075 high strength aluminum alloy by control variable method. The marginal distribution functions were established, and the multivariate joint distribution function was constructed by the optimized Copula function. Based on the Copula function theory and the joint function model, the global, local and tail relationship between cutting force and surface roughness was analyzed. The results show that the cutting force has obviously positive correlation with surface roughness. The correlation structure is centrosymmetric, and the correlation degrees at the both ends are larger than that at the center. The tail correlation coefficient tends to zero, which illuminates that the tail correlation degree is small.
		2018 Vol. 39 (2): 174-178 [Abstract] ( 1014 ) [HTML 1KB] [ PDF 1422KB] ( 1292 )

	179	Image segmentation method of lettuce leaf based on improved Otsu algorithm
		SUN Jun, SONG Jia, WU Xiao-Hong, LI Yu-Ting
		To solve the disadvantages of traditional Otsu algorithm with large computation and bad realtime performance, a new PSO+Otsu(S) segmentation method was proposed. The RGB color space was converted into HSV color space, and the S component image was extracted. A new updating strategy of inertia weight coefficient w was proposed for the basic particle swarm optimization algorithm, and the improved particle swarm optimization algorithm was used to search the optimal threshold. The optimal threshold was used as the threshold of Otsu algorithm, and the Otsu algorithm was used to segment the S component image. Finally, the segmentation image of lettuce leaf was obtained. The results show that the proposed segmentation method is not only suitable for single leaf image, but also suitable for canopy leaf image. When the algorithm is used to segment the single image of lettuce leaf and the canopy image of lettuce leaf, the program running times are 118 ms and 126 ms, and the iteration numbers are 6 and 5 times, respectively. Compared with the Otsu algorithm and the standard PSO+Otsu algorithm, the proposed algorithm can not only shorten program running time, but also improve the accuracy of image segmentation with better realtime performance.
		2018 Vol. 39 (2): 179-184 [Abstract] ( 1050 ) [HTML 1KB] [ PDF 1731KB] ( 1749 )

	185	Order preserving encryption scheme based on nonlinear mapping in cloud environment
		YU Peng, PAN Sen-杉, ZHANG Jian-Ming
		To improve efficiency and ensure security, a nonlinear mapping order preserving encryption scheme (nOPE) was proposed. By nonlinear mapping and nonlinear splitting, the data distribution and the data frequency were hidden. The system model of order preserving encryption with problem model and adversary model was introduced in cloud environment. The order preserving encryption scheme was proposed for the problem model, and the correctness was verified. The scheme security under the two kinds of attack of adversary model was analyzed, and the scheme efficiency was compared with those of other different order preserving schemes. The results show that the proposed scheme can resist statistical attack and realize INDDNCPA with good security. The average encryption time per hundred thousand encrypted data is about 30 ms with good efficiency, and the scheme can be deployed and implemented in any programmable language with good programmability.
		2018 Vol. 39 (2): 185-193 [Abstract] ( 955 ) [HTML 1KB] [ PDF 1767KB] ( 1437 )

	194	Rotor structure optimization of permanent magnet synchronous generator builtin type U
		WEN Jia-Bin, SONG Chun-Jie, FU Yao, GUO Ping-Ping
		To solve the problems of tooth harmonic with high voltage distortion and cogging torque for permanent magnet synchronous generator(PMSG), the rotor structure of U type PMSG was optimized， and the cause of cogging torque was analyzed. Taking 6 pole PMSG with 72 slots as example, the effects of magnetic pole shift and nonuniform air gap on the electromagnetic properties of PMSG were analyzed by finite element method. The influence of the position of rotor axial cooling channel on PMSG performance was also studied. The results show that the magnetic pole shift can make the phase of cogging torque periodically change. When the magnetic pole offsets 0.5 tooth distance, the corresponding cogging torque is the smallest with about 25% of the original value. The tooth harmonic content, the voltage distortion rate and the cogging torque are decreased with the increasing of eccentricity of nonuniform air gap. When the position of rotor ventilation duct is suitable, the magnetic flux density in the magnet surface with maximum degaussing risk is biggest, which shows that the demagnetization risk of permanent magnets can be reduced by the appropriate rotor vents position. For the motor, the maximum magnetic density at the minimum magnetic density surface of permanent magnetic steel is 0.331 7 T when the rotor vents are shifted 2 degrees of mechanical angle.
		2018 Vol. 39 (2): 194-198 [Abstract] ( 1014 ) [HTML 1KB] [ PDF 1482KB] ( 1648 )

	199	Seismic response analysis of basin site under SV wave with different incident angles
		LI Chuan-Xun, DING Wen-Chang, JIN Dan-Dan, LIU Heng
		To analyze the ground motion response of basin site under seismic wave with different incident angles, based on computing platform of ABAQUS, the basin model with fixed slope angle of 45°and Dirac pulse as inputting SV wave was established by explicit FE method, and the peak ground displacements(PGD) were obtained. The results show that when the incident angles of input waves are increased in sequence from 0° to 5°, 10°, 15°, 20°, 25° and 30°, the surface PGD of basin are increased with latter decreasing. The surface PGD reaches the maximum value when the incident angle is 10°, which is 7.69 times of the amplitude of input seismic wave. The analysis results are partially unsafe if the vertical incidence is considered. Compared with vertical incidence case, the edge effect of basin is more significant under seismic wave with different incident angles, and the maximum value of edge PGD is about 1.3 times of that in the center of basin. The seismic response focus area gradually shifts to the right side of basin when the incident angle is increased.
		2018 Vol. 39 (2): 199-203 [Abstract] ( 1000 ) [HTML 1KB] [ PDF 2590KB] ( 2014 )

	204	Design of signal acquisition circuit based on STM32 and FPGA
		WANG Fei, ZHAO Niu-Jie, HAO Zhi-Chao, WANG Yan-Yan, DI Li-Xia
		WANG Fei, ZHAO Niujie, HAO Zhichao, WANG Yanyan, DI Lixia
		2018 Vol. 39 (2): 204-210 [Abstract] ( 1929 ) [HTML 1KB] [ PDF 1969KB] ( 2842 )

	211	Effects of Sr and ultrasonic vibration on microstructures and mechanical properties of ascast A380 alloy
		LEI Ji-Ping, YU Jian-Wu, LI Cheng-Bo, CHEN Jian-Mei, LUO Hong
		The effects of 0～0.25% Sr and ultrasonic vibration (UV) on microstructure and mechanical properties of A380 alloy were investigated. The results show that the microstructure in A380 alloy can be refined significantly, and the αAl phase are changed from coarse dendrite into fine nondirectional dendrites with globular structure, while the eutectic Si phase are changed from coarse acicular into vermicular, spot ones and fibrous. The desirable refinement of the microstructure in A380 alloy is obtained with 0.15% Sr. Tensile strength, yield strength, elongation and hardness of the ascast A380 with 0.15% Sr addition are 305 MPa, 219 MPa, 3.78% and 106 BHN, and those are respective 318 MPa, 227 MPa, 3.99% and 108 BHN under 0.15% Sr addition with UV. The smallest grain size is 42 μm, and the largest shape factor is 0.71 with 0.15% Sr addition under UV.
		2018 Vol. 39 (2): 211-216 [Abstract] ( 947 ) [HTML 1KB] [ PDF 2570KB] ( 1539 )

	217	Influence of laser shock processing on high temperature corrosion behavior of 42CrMo alloy steel
		LI Chuan-Jun, LI Kai, HUANG Wan-Wan, LU Yi-Shun, 吕Dong-Ming , WANG Zhi-Qiang, YU Ting, HAN Bin
		The laser shock processing(LSP) was carried out for 42CrMo alloy steel with high energy nanosecond pulse laser. Residual stress, hardness and roughness of 42CrMo alloy steel were determined after LSP. The high temperature corrosion tests of untreated and treated samples by LSP were conducted. The surface microtopography of 42CrMo alloy steel was observed by scanning electron microscope(SEM) to investigate the high temperature corrosion resistance of 42CrMo alloy steel. The results show that the corrosion morphology of the specimen after LSP is obviously better than that without LSP. The enhancement of high temperature corrosion resistance of 42CrMo steel after LSP is mainly due to the existence of residual compressive stress layer on material surface, which can inhibit the oxide film from falling off and improve the high temperature corrosion resistance. Compared with small energy laser shock, the large energy impact can greatly increase the compressive residual stress of specimen surface and enhance the influence of residually compressive stress.
		2018 Vol. 39 (2): 217-221 [Abstract] ( 859 ) [HTML 1KB] [ PDF 1554KB] ( 1708 )

	222	Design feature sensitivity analysis for joint pavement concrete pavement faulting
		WANG Wei-Na, QIN Yu, 吕Hao-Wen , YAN Qiang, HE Xiao-Ying
		Based on the longterm pavement performance (LTPP) faulting data, the sensitivity analysis was divided into two steps. In the first step, 5 methods of correlation analysis, variance analysis, grey correlation analysis, principal component analysis and neural network method were compared. Graphical analysis was used to verify the accuracy. The optimal analysis method and the key design feature were presented. In the second step, the whole data were divided into two datasets of dowel and nodowel sections. Correlation analysis and variance analysis were used to analyze the sensitivity of design feature. With the graphical analysis, the design feature sensitivity for dowel and nodowel sections was also analyzed, and the suggestions for controlling faulting were proposed. The results indicate that correlation analysis performs the best. For sections with dowel bar, setting dowel bar is the most effective method. For sections without dowel bar, decreasing joint space is more effective method.
		2018 Vol. 39 (2): 222-229 [Abstract] ( 909 ) [HTML 1KB] [ PDF 5266KB] ( 1425 )

	230	Impervious performance of fiber asphalt chip seal under hydrodynamic pressure
		QIN Xiao, SHEN Ai-Qin, GUO Yin-Chuan, LI Zhen-南, FAN Li
		Based on cracking simulation of original pavement, the infiltration tests were carried out under hydrodynamic pressure, and the effects of fiber content, aggregate lithology, diameter and modified emulsified asphalt content on impervious performance of seal were investigated. The requirements of impervious performance in different traffic environments were proposed, and the strengthen mechanisms of impervious performance for seal were revealed based on SEM test at mesoscopic scale. The results indicate that fiber content shows more dramatical impact on impervious performance than aggregate lithology when the thru hole aperture of perforated plate is less than 3 mm, while it shows the opposite effect when the aperture is more than 3 mm. With the increasing of aperture, the influence of asphalt content on impervious performance is decreased. The thicker the asphalt film is, the less the influence of aperture on impervious performance is. VMA of seal with 5-10 mm aggregate is higher than those with 3-6 mm and 4-8 mm aggregates under the same content, which minifies the bonding areas by asphalt with decreased adhesion. The physical and chemical absorption of glass fiber on asphalt can strengthen the adhesion between asphalt and aggregate, and the fibers distribute uniformly in the seal to inhibit the cracks for protecting asphalt film and to strengthen the impervious performance of seal effectively.
		2018 Vol. 39 (2): 230-235 [Abstract] ( 919 ) [HTML 1KB] [ PDF 2092KB] ( 1159 )

	236	Shear stress analysis of asphalt pavement based on transverse contact stress
		ZHANG Lan-Feng, WANG Hai-Nian
		ABAQUS software was adopted to establish the model of semirigid pavement structure with uniaxial twowheel load mode and each tire load simplified to five mobile nonuniform load with different stress, length and width. Compiling Dload and Utracload subroutines by Fortran program, the vertical, horizontal and transverse loads were applied. The relationship between transverse stress and pavement shear stress was analyzed. The results show that the pavement surface shear stress distribution has significant relationship with transverse stress. When the lateral friction coefficient is increased, the positive shear stress is decreased with increased negative shear stress. The location of the maximum positive shear stress is at the tire edges of both sides. The negative shear stress at intermediate load belt is increased gradually and over tire edge shear stress, and the maximum negative shear stress transfers from the edge to the middle. The lateral friction coefficient is increased linearly with different point shear stress at different asphalt pavement layer. The influence of lateral friction coefficient on surface shear stress is most obvious, while in other layers of asphalt pavement, the influence on shear stress is decreased with the increasing of depth.
		2018 Vol. 39 (2): 236-241 [Abstract] ( 906 ) [HTML 1KB] [ PDF 2860KB] ( 1585 )

	242	Preparation technology of modified asphalt SBSrubber powderHDPE composite
		HE Rui, HUANG Xin, WU Jiang-Tao, WANG Zhen-Jun
		Using SK90# matrix asphalt, the orthogonal experiment with 6 test variables was adopted to prepare composite modifying asphalt. The determined technical indexes were analyzed by gray relational analysis to obtain the optimum preparation process parameters of composite modifying asphalt. The results show that the softening point and 5 ℃ ductility of asphalt are significantly improved by SBSrubber powderHDPE, and the elastic recovery rate of the twentysecond group sample reaches 60% with good elasticity. The optimum technological parameters for preparing SBSrubber powderHDPE modifying asphalt are determined by gray relational analysis with modifier SBS content of 5.0%, modifier powder content of 20.0%, modifier HDPE of 4.5%, shear rate of 4 500 r·min-1, shear time of 45 min and shear temperature of 170 ℃. SBS and HDPE are intertwined with each other under the action of high temperature shearing to form threedimensional network structure with polymer as dispersion medium and asphalt as dispersed phase, and the overall performance of composite modifying asphalt is improved.
		2018 Vol. 39 (2): 242-248 [Abstract] ( 1046 ) [HTML 1KB] [ PDF 1321KB] ( 1256 )

江苏大学学报（自然科学版）

　

News

　

·	关于近期网络不稳定情况的说明

·	Our journal has be included in JSTChina Database

·	Our journal has be selected for the 2015-2016 China Science Citation Database (CSCD)

　　　　　　　　　　More

　

Links

　

·	Chinese Library Classification Number

·	Society of China University Journals

·	China National Knowledge Infrastructure

·	Chinese Sciencepaper Online

·	Transactions of the Chinese Society for Agricultural Machinery

·	Journal of Southeast University：Natural Science Edition

　　　　　　　　　　More

Copyright © 2011 Journal of Jiangsu University(Natural Science Eidtion)
Support by Beijing Magtech Co.Ltd E-mail：support@magtech.com.cn