[an error occurred while processing this directive]
排灌机械工程学报
   Home  About Journal  Editorial Board  Instructions for Authors    中文 
 
　

Office Online

 　
　  Author Center
　  Peer Review
　  Editor Work
　  Office Work
　  Editor-in-chief
　

Journal Online

 　
　  Forthcoming Articles
　  Current Issue
　  Next Issue
　  Archive
　  Read Articles
　  Download Articles
　  Email Alert
　  
Quick Search  
  Advanced Search
Journal of Drainage and Irrigation Machinery Engin
 
2018 Vol.36 Issue.3
Published 2018-03-25
article
article
1
2018 Vol. 36 (3): 1- [Abstract] ( 313 ) [HTML 1KB] [ PDF 7341KB] ( 1057 )
2
2018 Vol. 36 (3): 2- [Abstract] ( 352 ) [HTML 1KB] [ PDF 1117KB] ( 1140 )
185 Effects of tongue tip radius on performance and hydrodynamic load characteristics in centrifugal pump
GAO Bo*, YANG Li, ZHANG Ning, DU Wenqiang, YUAN Xiao
In order to investigate effects of volute tongue tip radius on performance and hydraulic load characteristics, unsteady flow fields in a centrifugal pump with the same impeller but different volutes in five tongue tip radii were simulated numerically. The hydraulic performance, pressure pulsation, blade loading and radial thrust on the impeller were acquired and analysed, and the predicted perfor-mance was compared with the experiment results, showing the numerical methods adopted in the paper were in a better accuracy. The results showed that the tip radius had a little effect on the hydraulic performance, but the best hydraulic efficiency could be achieved at a certain tip radius. When the dimensionless tip radius TR(tip radius-to-base circle radius ratio)was in a range of 0.09-0.24, the loa-ding across the blade pressure side and suction side was the minimum, i.e. the force acting on a blade exhibited the least variation from the leading to trailing edges. With increasing TR, the pressure fluctuation level in the pump reduced gradually, particularly the pressure amplitude at TR=0.03 was about 2 times the amplitude at TR=0.3 for blade passing frequency. The tip radius has a significant effect on impeller radial thrust. At the nominal flow rate, the radial thrust increased with increasing tip ra-dius, and at TR=0.3 the thrust was about 2.5 times the thrust at TR=0.03. 
2018 Vol. 36 (3): 185-190 [Abstract] ( 723 ) [HTML 1KB] [ PDF 5836KB] ( 1304 )
191
2018 Vol. 36 (3): 191-196 [Abstract] ( 527 ) [HTML 1KB] [ PDF 3247KB] ( 947 )
197 Impact of wall roughness on cavitating process in centrifugal pump
XU Weihui, HOU Xiao*, HU Meng, HE Xiaoke, WANG Weishu
To study the effect of wall roughness on cavitating process in centrifugal pumps, the steady internal flow in a centrifugal pump was simulated numerically by using ANSYS CFX. The fluid domains of the pump were generated by using Pro/E software. The RNG k-ε turbulence model and Zwart′s cavitation model,which doesn′t consider non-condensable gas in water, were applied in simulations. The numerical simulations of flow in the pump were conducted under design flow condition. Then the influences of wall roughness on cavitation characteristic and internal flow pattern were analyzed by changing the wall roughness of the blades. The results showed that an increased roughness led to a decline in the pump head and efficiency but an increase in the shaft power.The degree of influence of roughness on the pump performance in the critical and local cavitation states is more significant than that in the subcritical and supercritical cavitation conditions. The effect of roughness on turbulent kinetic energy in the pump is similar to the influence on the development of cavitation.A reduced wall roughness has a significant effect on the improvement of centrifugal pump characteristics, when the inlet pressure is 81.06 kPa and 101.33 kPa.
2018 Vol. 36 (3): 197-203 [Abstract] ( 573 ) [HTML 1KB] [ PDF 2631KB] ( 1456 )
204 Calculation of optimal compound cross-section dimensions channel with flat-bottom and parabolic side walls
ZHAI Donghan, HE Wuquan,*, LI Gang
To solve a few problems such as great depth and large amount of earthworks occurred when a parabolic cross-section is applied in large- and medium-sized channels, a channel with compound cross-section was proposed, which is subject to a flat bottom and two 2th-order parabolic side walls. Analytical formulas for determining the channel cross-sectional area and wetted perimeter were deduced. Based on the open-channel uniform flow theory, a relationship between flow and water depth was established for the channel when the channel cross-section profile was under optimal hydraulic condition. Additionally, a series of formulas for the optimal width-to-depth ratio, water depth, water surface width, cross-sectional area and wetted perimeter were deduced and programmed by using Mathcad software. It was shown that at flow Q=30 m3/s, the channel had 2.904 m water depth, 6.278 m water surface width and 13.604 m2 cross-sectional area under the optimal hydraulic condition. The channel cross-section area is 1.7% and 0.2% smaller than the channels respectively with ordinary trapezoidal cross-section, arc-bottomed trapezoidal cross-section at the same flow rate. This indicates that the proposed compound cross-section profile is better in hydraulics and earthwork cost in comparison with the two kinds of existing trapezoidal cross-section channels.
2018 Vol. 36 (3): 204-208 [Abstract] ( 556 ) [HTML 1KB] [ PDF 1243KB] ( 1275 )
209 Purification effects of surface flow constructed wetland in treating polluted river water
ZHANG Zhichao,, WANG Shuqian,*
To provide technical support for a demonstration project-efficient pollutant removal surface flow constructed wetland system, purification effects of the system on main pollutants such as nitrogen(TN)and ammonia nitrogen(NH+4-N)in Fuyang River were studied. A pilot experiment was carried out in Yongnian rainfall runoff test field of Handan at 430 mm/d hydraulic load with 0.5 d hydraulic retention time. The results showed that the system was subject to 51.89% and 47.00% avera-ge removal rates for TN and NH+4-N, respectively, exhibiting a good purification effect on polluted river water body. Based on the inflow water body quality during the trial, it turned out that the maximum working loads of the system were 8.95 mg/L and 2.16 mg/L for TN and NH+4-N, and the corresponding maximum removal rates were 60.00% and 56.48%, respectively. The TN and NH+4-N concentrations along the course were examined. It was identified that dissolved oxygen(DO)was one of the key factors influencing TN and NH+4-N removal, especially for NH+4-N removal. The trend of NH+4-N concentration slightly increases in the upper course, significantly decreases in the middle and gets stable in the tail end. The TN concentration showed a steadily decreasing trend along the course.
2018 Vol. 36 (3): 209-214 [Abstract] ( 485 ) [HTML 1KB] [ PDF 1796KB] ( 1267 )
215 Numerical simulation on effects of number of blades with plate added at blade trailing edge on torque coefficient of vertical axis wind turbine
LI Yan,*, ZHAO Shouyang, JIANG Yu, FENG Fang,, ZHANG Tingting
In order to explore the influence of number of blades with plate added at the blade trailing edge on the aerodynamic characteristics of vertical axis wind turbine(VAWT), the torque coefficient of a VAWT with various numbers of blades was analyzed. The improvement in the flow field around the turbine blade was identified under different conditions of number of blades. The torque characteristics and static starting performance were calculated by numerical simulation for a SB-VAWT with seven curved plate lengths for 2, 3 and 4 blades based on a typical airfoil NACA0018, which has been often used in VAWTs. The simulated results showed that the aerodynamic characteristics of this lift-type VAWT were affected by the number of blades and the length of the curved plate. The increasing plate length can improve the performance of the wind turbine due to the drag, but could suppress the change in torque coefficient due to the increase of number of blades. Under the condition of different numbers of blades, the optimum curved plate length can optimize the static starting performance of the wind turbine. At different numbers of blades, a properly extended curved plate can optimize the static starting performance of the turbine, but the optimized performance occurs at different azimuth angles. Specially, the optimized performance is the best when the number of blades is 2, and the average torque coefficient is increased by 40%. This study has provided a basis for the design and optimization of blade trailing edge for VAWTs. 
2018 Vol. 36 (3): 215-222 [Abstract] ( 638 ) [HTML 1KB] [ PDF 3216KB] ( 856 )
223 Influences of drag blade on aerodynamic performance of vertical-axis wind turbine with lift-drag compound rotor
QU Jianjun*, WANG Jingyuan, ZHAO Yue, ZHANG Lei
In order to obtain more energy from wind, the rotor size of vertical-axis wind turbines has been designed large by large. However, an enlarged rotor diameter can result in a difficulty for the rotor to start operation. A new type vertical-axis wind turbine with lift-drag compound rotor was proposed to solve this problem. Under the premise of keeping its lift blades unchanged, nine lift-drag compound rotors were established. The aerodynamics of the turbines with these rotors was numerically simulated by using Fluent. Influences of the drag blade radius and the distance L between the blade and the rotor shaft were studied based on the starting performance and operating efficiency. After the best combination of radius and position for the drag blade obtained, a comparison in performance was made with the lift type vertical-axis wind turbine. The results show that the starting performance of the wind turbine is better when the radius and the distance L get larger. In terms of operational efficiency, when the tip speed ratio is 0.5-1.0, the radius and the distance L exhibit a little effect on the power coefficient. When the tip speed ratio exceeds 1, however, increased two factors can reduce the power coefficient. Although the operation efficiency of the wind turbine with lift-drag compound rotor is a bit low, its startup performance has been improved obviously.
2018 Vol. 36 (3): 223-229 [Abstract] ( 560 ) [HTML 1KB] [ PDF 1981KB] ( 929 )
230 Numerical simulation of new variable-pitch strategy for H-type wind turbine
QIAN Siyue, ZHAO Zhenzhou*, TIAN Chen, WANG Ruixin, ZENG Guanyu, ZHENG Yuan
When the blades of an H-type wind turbine rotate in a range of 0°-180° azimuth angles, the torque coefficient of the turbine is negative due to zero angle of attack, but also the torque coefficient keeps negative or small value in the vicinity of these two azimuth angles. Therefore, the overall performance of wind turbine must suffer from a more significantly degraded effect. In the paper, a new variable-pitch strategy was proposed and a pitch angle curve was designed at the tip speed ratio of 4.5 to improve the performance at small angle of attack. Additionally, the aerodynamics performance of the turbine with the new variable-pitch curve was simulated by using the sliding mesh technique and the RNG k-ε turbulence model based on Fluent software, and compared with the performance of the turbine with fixed-pitch blades. The results show that the torque coefficient of the wind turbine with new variable-pitch blades increases obviously, and its increment can be as high as 14%. In the range of 30°-80° azimuth angles, the torque coefficient is improved greatly. The coefficient also exhibits a significant improvement when the azimuth angle is a range of 180°-360°(excluding 270°). The flow field in the turbine with new variable-pitch shows a noticeable change in comparison with the turbine with fixed-pitch. Specially, the difference in velocity magnitude is larger and the low-velocity area becomes bigger in the new turbine. According to the vorticity contours, it is observed that the probability of one blade being in the wake of the other blade has been curtailed effectively by the proposed variable-pitch curve. As a result, the impact of wake on the overall performance of the turbine is relieved.
2018 Vol. 36 (3): 230-236 [Abstract] ( 617 ) [HTML 1KB] [ PDF 1973KB] ( 1073 )
237 Experiments on aerodynamic characteristics of H-type wind turbine rotor with novel airfoil shape
ZHU Jianyong,, LIU Peiqing*
In order to improve self-starting capability of H-type wind turbines, a novel airfoil containing just leading edge and one airfoil surface was designed exploratively, and wind tunnel experiments on the wind turbine rotor with this airfoil were carried out to investigate the start-up behavior and power output characteristics at different wind speeds. Effects of Reynolds number and solidity on aerodynamic characteristics of the turbine rotor were clarified. The experimental results indicate the turbine rotor adopting the novel airfoil is capable of self-start at low wind speeds, exhibiting an excellent self-start behavior, especially for the turbine rotor with large solidity. In addition, the turbine rotor with large solidity is mainly driven by the drag and essentially belongs to drag-type wind turbine, but it is subject to a relatively high power coefficient. Considering the self-start behavior and power output characteristics, the proposed airfoil is more suitable for the H-type wind turbine at large solidity.
2018 Vol. 36 (3): 237-242 [Abstract] ( 511 ) [HTML 1KB] [ PDF 2129KB] ( 964 )
243 Effect of wind speed and airfoil camber on aerodynamic performance of vertical axis wind turbines
SONG Chenguang,, ZHAO Zhenzhou*, WU Guoqing,, ZHU Weinan,, LIU Zewei
To investigate the effect of wind speed and airfoil camber on the aerodynamic performance of vertical axis wind turbine(VAWT), three wind speeds such as 4, 8 and 12 m/s were specified as the design speeds and four airfoils namely NACA0015, NACA2415, NACA4415 and NACA6415 were selected as the design airfoils. 2D unsteady numerical simulations of a small H-type VAWT with these airfoils under these wind speeds were conducted to assess the CP-λ, Pa-n and Qa-n characteristic curves. The results showed that wind speed and airfoil camber both had a great impact on the aerodynamic performance. Wind speed mainly affects the CP(Pa)value of rotor, range of tip speed ratio and efficient operation region width, which all increase with increasing wind speed. Airfoil camber mainly affects the CPmax value of rotor, range of tip speed ratio, efficient operation region width, CP(Pa)value of rotor, economy and starting performance. However, the wind speed almost has no effect on the determination of airfoil camber. Considering various factors observed, the airfoil with a camber of 0-2% is the best choice for VAWTs.
2018 Vol. 36 (3): 243-249 [Abstract] ( 602 ) [HTML 1KB] [ PDF 1629KB] ( 1085 )
250 Analysis on application of vertical axis wind turbines in Qinghai-Tibet Plateau
ZHAO Bin,, MA Haipeng,, ZHAO Yuanxing, LUOSONG Zeren, WANG Jianwen*
Most parts of the Qinghai-Tibet Plateau belongs to a wind energy resources available area, but variable wind direction characteristic limits the use of horizontal axis wind turbine. Firstly, the distribution and characteristics of wind energy resources in the Qinghai-Tibet Plateau are analyzed. Then, the influence of air density on the output characteristics of vertical axis wind turbines is addressed by using analytical method according to the unique climatic conditions in the plateau. Thirdly, the output characteristics of a vertical axis wind turbine at the air density of 4 000 m altitude is predicted by employing numerical simulation and compared with these under the standard air state. Finally, the influences of special factors such as illumination, radiation, icing and lightning on the turbine are summarized. The results show that the air density has a little influence on the power coefficient, but has a great effect on the output power. At the same wind speed, the output power of the turbine at 4 000 m altitude with the air density of ρ1=0.843 7 kg/m3 is about 0.60-0.67 times the power in the area of ρ0=1.225 0 kg/m3. According to the results analyzed, the methods for updating wind turbine design and the improvement measures to deal with the environmental factors are put forward. The results in the paper can provide reference for the popularization and application of vertical axis wind turbines in plateau operational conditions. 
2018 Vol. 36 (3): 250-256 [Abstract] ( 562 ) [HTML 1KB] [ PDF 1895KB] ( 1176 )
257 Effects of fertilizer application rate of drip irrigation fertilization in various growing stages on growth and water use efficiency of potato in Yulin City
JIAO Wanru, ZHANG Fucang,*, GAO Yue, HOU Xianghao, FAN Junliang, LI Zhijun
In order to explore effects of fertilizer application rate on growth, yield and water use efficiency of potato in drip irrigation fertilization, a local cultivar-′Zihuabai′ potato in Yulin was targeted and a series of pot cultivating experiments were conducted at various fertilizer levels in different growth stages. Eight treatments(T1(0-0.2-0.55-0.25), T2(0-0.3-0.5-0.2), T3(0.1-0.2-0.5-0.2), T4(0.1-0.2-0.45-0.25), T5(0.1-0.3-0.4-0.2), T6(0.2-0.2-0.4-0.2), T7(0.2-0.3-0.4-0.1), and T8(0.2-0.3-0.3-0.2))were established based on the principle such as a less fertilizer application rate(20%, 30%, 40% and 50%)in the early stages(seedling and tuber formation stages, ES), a higher rate(80%, 70%, 60% and 50%)in the later stages(tuber enlargement and starch accumulation stages, LS). The results show that the LAI(leaf area index)and dry mass value are all presented with treatments ES0.4-0.5>ES0.2-0.3 in seeding and tuber forming stages, treatments ES0.2 is better than ES0.3-0.5 in tuber enlargement and starch accumulation stages, but the LAI and dry mass decreases significantly in T7 treatment in starch accumulation maturation stage for treatments T1 and T2, fertilization starts at tuber formation stage, a higher LAI and a more dry mass are obtained in tuber enlargement, starch accumulation and harvesting periods. For dry mass transport, the performance of dry mass accumulation of tuber after flowering is ES0.2>ES0.3-0.5, and the tuber dry mass accumulation is mainly caused by the assimilation after flowering. The variation of yield is ES0.2>ES0.5(except T7)>ES0.4(except T5)>ES0.3( except T2). The variation of the weight of commercial potato per plant is consistent with that of the yield; however, there isn′t a general correlation among averaged single tuber weight, single commodity weight and number of tubers per plant. The trend of water use efficiency and partial fertilizer productivity are similar to that of yield, and there is no statistical significance in water consumption among various treatments. In summary, from the yield and water utilization efficiency point of view, the optimum fertilizer application rates should be 20% in seedling and tuber formation periods(no fertilization at seedling stage), 55% in tuber expansion period and 25% in starch accumulation period, respectively, under our experimental conditions.
2018 Vol. 36 (3): 257-266 [Abstract] ( 615 ) [HTML 1KB] [ PDF 1488KB] ( 1000 )
267 Effects of water-fertilizer coupling on physiological characteristics of facility planting cowpea
YIN Changqing,, FEI Liangjun*, LIU Lihua, DAI Zhiguang, LIU Le, WANG Aike
In order to explore the response of facility planting cowpea to water-fertilizer coupling, the effects of water-fertilizer coupling on growth, physiological, yield and quality of facility planting cowpea are studied with drip fertilization in greenhouse, so as to develop a high-yield, better quality and efficient drip fertilization system. This experiment was designed with two factors at three levels each, namely 3 irrigation levels and 3 fertilization levels, thus there are nine treatments totally. The results revealed that the effect of drip fertilization on plant height and stem diameter of cowpea was statistically significant, but also a suitable water-to-fertilizer ratio was beneficial to plant growth during the whole growth period; unfortunately, a large water-to-fertilizer ratio can cause an excessive growth, thereby affecting yield and quality formation. The net photosynthetic rate, stomatal conductance and transpiration rate showed a bimodal curve with proceeding growth period. Specially, the photosynthesis was weaker because of a lower temperature in seeding stage, so increasing water and fertilizer was beneficial to the improvement of photosynthetic index. In sprouting period, the photosynthesis was strengthened, me-dium irrigation volume and high fertilizer level were the best, and there was no statistical significance between medium irrigation volume and medium fertilizer level. The photosynthetic capacity was the highest in pod bearing stage, increased firstly and then decreased with increasing irrigation and fertilizer levels, eventually kept less variation, and the demand on water and fertilizer was the maximum. The yield and water use efficiency firstly increased and then decreased with increasing irrigation level and fertilizer quota. Medium irrigation volume and fair fertilizer level could improve water use efficiency without affecting yield. Under these conditions, the yield and water use efficiency have reached 28 598 kg/hm2 and 95.33 kg/m3, respectively. Additionally, the water use efficiency was more sensitive to irrigation volume than to fertilizer, but the effect of interaction between irrigation volume and fertilizer level was not statistically significant. An analysis of quality comprehensive indices showed that medium water and medium fertilizer levels could result in the best index values and made the increment in nitrate content controllable, particularly VC, soluble protein and soluble sugar were up to 285.3 mg/kg, 90.48 g/kg, 52.82 mg/g, respectively.
2018 Vol. 36 (3): 267-276 [Abstract] ( 1287 ) [HTML 1KB] [ PDF 1574KB] ( 896 )
排灌机械工程学报
　

WeChat QR code
　

News

 　
· Call for paper of The 14th Asian International Conference on Fluid Machinery(AICFM14)
· Call for paper of the 2nd International Symposium of Cavitation and Multiphase Flow (ISCM 2016)
· JDIME have be selected for the 2015-2016 China Science Citation Database (CSCD)
· CALL FOR PAPERS and 2nd ANNOUNCEMENT"The 7th International Conference on Pumps and Fans(ICPF2015)"
· The journal won the first prize of "excellent China sciencepaper online journal" again
· WeChat is Running
· A New Column “Irrigation and Drainage Equipment Manufacturing Technology”Setting Up
· CALL FOR PAPERS “8th INTERNATIONAL SYMPOSIUM ON PUMPING MACHINERY”
　　　　　　　　        　　More 
　

WeChat QR code

主管单位
 江苏省教育厅
主办单位
 江苏大学
协办单位
 中国农业机械学会排灌机械分会
 国家水泵及系统工程技术研究中心
 中国农业工程学会农业水土工程专业委员会
主　　编
 袁寿其
编辑出版
 《排灌机械工程学报》编辑部
责任编辑
徐云峰  张文涛 陈建华
谈国鹏  朱漪云 盛    杰
　

Links

 　
· KSB
· National Research Center of Pumps
　　　　　　　　        　　More 
 

Copyright © 2011 Journal of Drainage and Irrigation Machinery Engineering
Support by Beijing Magtech Co.Ltd   E-mail: support@magtech.com.cn