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RESEARCH OF THE DYNAMIC CHARACTERISTICS ON A NEW HYDRAULIC SYSTEM OF ELECTRO-HYDRAULIC HAMMER 被引量:9
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作者 Li Yongtang Lei Bufang Department of Mechanical Engineering,Taiyuan Heavy Machinery Institute Shi Enxiu Xi’an University of Science and Technology 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第2期171-174,共4页
A new typed hydraulic system of electro hydraulic hammer is researched and developed By means of power bond graphs the modeling and simulation to the dynamic characteristics of the new hydraulic system are performed... A new typed hydraulic system of electro hydraulic hammer is researched and developed By means of power bond graphs the modeling and simulation to the dynamic characteristics of the new hydraulic system are performed The experimental research which is emphasized on the blowing stroke is also performed It is proved from the result of simulation and experiment that this new hydraulic system possesses such advantages as simplification of structure,flexibleness of operation and reliability of working Especially it possesses better dynamic characteristics 展开更多
关键词 ELECTRO hydraulic hammer hydraulic system Dynamic characteristics sIMULATION
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RESEARCH ON THE ENERGY ECONOMIZATION OF ELECTRO-HYDRAULIC HAMMER 被引量:10
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作者 Lei Bufang Li Yongtang Liu Jiansheng (Department of Mechanical Engineering, Taiyuan Heavy Machinery Institute) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第1期54-69,共6页
The research on the driving principle and economization of energy of electro-hydraulic hammer is discussed. By means of the balance chart of energy, the method and formulas to calculate every level efficiency and the ... The research on the driving principle and economization of energy of electro-hydraulic hammer is discussed. By means of the balance chart of energy, the method and formulas to calculate every level efficiency and the total efficiency of steam drived hammer are formed.With the aid of actual data of plants,the actual efficiency of steam drived hammer is got. The working principle and the driving system of electro-hydraulic hammer are introduced. The procedure of energy energy of this hammer is analyzed. The utilization ratio of energy of this type of hammer is got. It is shown that the efficiency of electro-hydraulic hammer is 7 times as much as that of steam drived hammer. 展开更多
关键词 steam hammer Electro-hydraulic hammer Economization
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Structure Parameters Optimization Analysis of Hydraulic Hammer System 被引量:1
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作者 Guoping Yang Jian Fang 《Modern Mechanical Engineering》 2012年第4期137-142,共6页
In order to improve the impact performance, the structure of hydraulic hammer should be optimized. In this paper, the ranges of eight vital structure parameters of piston and reversing valve system of hydraulic hammer... In order to improve the impact performance, the structure of hydraulic hammer should be optimized. In this paper, the ranges of eight vital structure parameters of piston and reversing valve system of hydraulic hammer were selected firstly;and then found the best value of different parameters under experiments with the method of computer optimization and the parametric analysis method provided by ADAMS software. These methods worked and the best design values of parameters of hydraulic hammer were obtained. At last, the optimal impact energy of virtual prototype of hydraulic breaking hammer was calculated and compared with the original impact performance. The results reveal that impact performance of hydraulic hammer has been improved significantly. 展开更多
关键词 hydraulic hammer sTRUCTURE PARAMETERs Optimization Analysis IMPACT Performance ADAMs
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Water hammer in coarse grained solid liquid flows in hydraulic hoisting for ocean mining
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作者 韩文亮 王光谦 +2 位作者 吴保生 刘少军 邹伟生 《中国有色金属学会会刊:英文版》 CSCD 2002年第3期508-513,共6页
The particles of polymetallic nodules in hydraulic hoisting flows that are used for mining in deep sea are rather coarse, therefore their flow velocity is smaller than that of the surrounding water. The characteristic... The particles of polymetallic nodules in hydraulic hoisting flows that are used for mining in deep sea are rather coarse, therefore their flow velocity is smaller than that of the surrounding water. The characteristics of solid liquid flows such as their density, concentration, elastic modulus and resistance were discussed. The wave propagation speed and the continuity and momentum equations of water hammer in coarse grained solid liquid flows were theoretically derived, and a water hammer model for such flows was developed. 展开更多
关键词 水锺 固液两相流 海上采矿 水力提升
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电液3-UPS/S并联稳定平台参数振动特性分析
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作者 袁晓明 王维锜 +1 位作者 庞浩东 张立杰 《振动与冲击》 EI CSCD 北大核心 2024年第5期52-61,共10页
针对电液3-UPS/S并联稳定平台驱动液压缸的压力脉动所产生的参数振动,建立了稳定平台的参数振动方程并利用多尺度法求解了主共振响应与组合共振响应的一次近似解;分析了主共振与组合共振响应特性以及振动幅值在初始工作空间内的变化规律... 针对电液3-UPS/S并联稳定平台驱动液压缸的压力脉动所产生的参数振动,建立了稳定平台的参数振动方程并利用多尺度法求解了主共振响应与组合共振响应的一次近似解;分析了主共振与组合共振响应特性以及振动幅值在初始工作空间内的变化规律,最后采用四阶龙格库塔法与模态试验对参数振动模型进行验证。结果表明:数值解与理论解之间的最大误差为4.20%,固有频率理论值与试验值之间的最大误差为4.66%,可验证参数振动模型的正确性。 展开更多
关键词 电液3-UPs/s并联稳定平台 压力脉动 参数振动 多尺度法 振动特性
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RELIABILITY-BASED DESIGN AND ANALYSIS ON HYDRAULIC SYSTEM FOR SYNTHETIC RUBBER PRESS 被引量:8
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作者 YaoChengyu ZhaoJingyi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第2期159-162,共4页
To overcome the design limitations of traditional hydraulic control systemfor synthetic rubber press and such faults as high fault rate, low reliability, highenergy-consuming and which always led to shutting down of p... To overcome the design limitations of traditional hydraulic control systemfor synthetic rubber press and such faults as high fault rate, low reliability, highenergy-consuming and which always led to shutting down of post-treatment product line for syntheticrubber, brand-new hydraulic system combining with PC control and two-way cartridge valves for thepress is developed, whose reliability is analyzed, reliability model of the hydraulic system for thepress is established by analyzing processing steps, and reliability simulation of each step and thewhole system is carried out by software MATLAB, which is verified through reliability test. Thefixed time test has proved not that theory analysis is sound, but the system has characteristics ofreasonable design and high reliability, and can lower the required power supply and operationalenergy cost. 展开更多
关键词 synthetic rubber près hydraulic system RELIABILITY sIMULATION Fixedtime test
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Ride quality evaluation of the soil compactor cab supplemented by auxiliary hydraulic mounts via simulation and experiment 被引量:2
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作者 Nguyen Van Liem Zhang Jianrun +1 位作者 Hua Wenlin Wang Peiling 《Journal of Southeast University(English Edition)》 EI CAS 2019年第3期273-280,共8页
In order to evaluate the ride quality of the soil compactor cab supplemented by the auxiliary hydraulic mounts (AHM), a nonlinear dynamic model of the soil compactor interacting with the off-road deformable terrain is... In order to evaluate the ride quality of the soil compactor cab supplemented by the auxiliary hydraulic mounts (AHM), a nonlinear dynamic model of the soil compactor interacting with the off-road deformable terrain is established based on Matlab/Simulink sofware. The power spectral density (PSD) and the weighted root mean square (RMS) of acceleration responses of the vertical driver s seat, the cab s pitch and roll angle are chosen as objective functions in low-frequency range. Experimental investigation is also used to verify the accuracy of the model. The influence of the damping coefficients of the AHM on the cab s ride quality is analyzed, and damping coefficients are then optimized via a genetic algorithm program. The research results show that the cab s rubber mounts added by the AHM clearly improve the ride quality under various operating conditions. Particularly, with the optimal damping coefficients of the front-end mounts c a 1,2 = 1 500 N · s/m and of the rear-end mounts c a 3,4 =2 335 N · s/m, the weighted RMS values of the driver s seat, the cab s pitch and roll angle are reduced by 22.2%, 18.8%, 58.7%, respectively. Under the condition of the vehicle travelling, with the optimal damping coefficients of c a 1,2 = 1 500 N · s/m and c a 3,4 =1 882 N · s/m, the maximum PSD values of the driver s seat, the cab s pitch and roll angle are clearly decreased by 36.7%, 54.7% and 50.6% under the condition of the vehicle working. 展开更多
关键词 off-road soil compactor dynamic model cab s rubber mounts auxiliary hydraulic mount ride quality
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Hydraulic model with roughness coefficient updating method based on Kalman filter for channel flood forecast 被引量:4
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作者 Hong-jun BAO Lin-na ZHAO 《Water Science and Engineering》 EI CAS 2011年第1期13-23,共11页
A real-time channel flood forecast model was developed to simulate channel flow in plain rivers based on the dynamic wave theory. Taking into consideration channel shape differences along the channel, a roughness upda... A real-time channel flood forecast model was developed to simulate channel flow in plain rivers based on the dynamic wave theory. Taking into consideration channel shape differences along the channel, a roughness updating technique was developed using the Kalman filter method to update Manning's roughness coefficient at each time step of the calculation processes. Channel shapes were simplified as rectangles, triangles, and parabolas, and the relationships between hydraulic radius and water depth were developed for plain rivers. Based on the relationship between the Froude number and the inertia terms of the momentum equation in the Saint-Venant equations, the relationship between Manning's roughness coefficient and water depth was obtained. Using the channel of the Huaihe River from Wangjiaba to Lutaizi stations as a case, to test the performance and rationality of the present flood routing model, the original hydraulic model was compared with the developed model. Results show that the stage hydrographs calculated by the developed flood routing model with the updated Manning's roughness coefficient have a good agreement with the observed stage hydrographs. This model performs better than the original hydraulic model. 展开更多
关键词 flood routing Manning's roughness coefficient updating method Kalman filter Froude number saint-Venant equations hydraulic model
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Performance analysis of semi-active cab’s hydraulic system of the vibratory roller using optimal fuzzy-PID control 被引量:1
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作者 Nguyen Van Liem Zhang Jianrun +1 位作者 Wu Zhenpeng Yang Xiuzhi 《Journal of Southeast University(English Edition)》 EI CAS 2019年第4期399-407,共9页
In order to evaluate the performance of semi-active cab’s hydraulic mounts(SHM)of the off-road vibratory roller with the optimal fuzzy-PID(proportional integral derivative)control,a nonlinear dynamic model of the veh... In order to evaluate the performance of semi-active cab’s hydraulic mounts(SHM)of the off-road vibratory roller with the optimal fuzzy-PID(proportional integral derivative)control,a nonlinear dynamic model of the vehicle interacting with off-road terrains is established based on Matlab/Simulink software.The weighted root-mean-square(RMS)acceleration responses of the driver’s seat heave and the cab’s pitch angle are chosen as objective functions.The SHM is then optimized and analyzed via the optimal fuzzy-PID control under different operation conditions.The simulations results show that the driver’s ride comfort and the cab shaking are greatly affected by the off-road terrains under various operating conditions of the vehicle,especially at the speed from 8 to 12 km/h on a very poor terrain surface of Grenville soil ground under the vehicle travelling.With SHM using the optimal fuzzy-PID control,the driver’s ride comfort and the cab shaking are clearly improved under various operation conditions of the vehicle,particularly at the speed from 6 to 7 km/h of the vehicle traveling. 展开更多
关键词 vibratory roller off-road terrains semi-active cab’s hydraulic system optimal fuzzy-PID(proportional integral derivative)control
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Global Dynamic Modeling of Electro-Hydraulic 3-UPS/S Parallel Stabilized Platform by Bond Graph 被引量:11
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作者 ZHANG Lijie GUO Fei +1 位作者 LI Yongquan LU Wenjuan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第6期1176-1185,共10页
Dynamic modeling of a parallel manipulator(PM) is an important issue. A complete PM system is actually composed of multiple physical domains. As PMs are widely used in various fields, the importance of modeling the ... Dynamic modeling of a parallel manipulator(PM) is an important issue. A complete PM system is actually composed of multiple physical domains. As PMs are widely used in various fields, the importance of modeling the global dynamic model of the PM system becomes increasingly prominent. Currently there lacks further research in global dynamic modeling. A unified modeling approach for the multi-energy domains PM system is proposed based on bond graph and a global dynamic model of the 3-UPS/S parallel stabilized platform involving mechanical and electrical-hydraulic elements is built. Firstly, the screw bond graph theory is improved based on the screw theory, the modular joint model is modeled and the normalized dynamic model of the mechanism is established. Secondly, combined with the electro-hydraulic servo system model built by traditional bond graph, the global dynamic model of the system is obtained, and then the motion, force and power of any element can be obtained directly. Lastly, the experiments and simulations of the driving forces, pressure and flow are performed, and the results show that, the theoretical calculation results of the driving forces are in accord with the experimental ones, and the pressure and flow of the first limb and the third limb are symmetry with each other. The results are reasonable and verify the correctness and effectiveness of the model and the method. The proposed dynamic modeling method provides a reference for modeling of other multi-energy domains system which contains complex PM. 展开更多
关键词 screw bond graph multi-energy domains 3-UPs/s parallel mechanism electro-hydraulic servo system
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Magma chamber growth models in the upper crust: A review of the hydraulic and inertial constraints
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作者 Eugenio Aragón Fernando J.D'Eramo +4 位作者 Lucio P.Pinotti Manuel Demartis José María Tubía Roberto F.Weinberg Jorge E.Coniglio 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第3期1211-1218,共8页
Finite volumes of magma moving in confinement, store hydraulic potential energy for the generation,control and transmission of power. The Pascal's principle in a hydraulic jack arrangement is used to model the ver... Finite volumes of magma moving in confinement, store hydraulic potential energy for the generation,control and transmission of power. The Pascal's principle in a hydraulic jack arrangement is used to model the vertical and lateral growth of sills. The small input piston of the hydraulic jack is equivalent to the feeder dike, the upper large expansible piston equivalent to the magmatic chamber and the inertial force of the magma in the dike is the input force. This arrangement is particularly relevant to the case of sills expanding with blunt tips, for which rapid fracture propagation is inhibited. Hydraulic models concur with experimental data that show that lateral expansion of magma into a sill is promoted when the vertical ascent of magma through a feeder dike reaches the bottom contact with an overlying, flat rigid-layer. At this point, the magma is forced to decelerate, triggering a pressure wave through the conduit caused by the continued ascent of magma further down(fluid-hammer effect). This pressure wave can provide overpressure enough to trigger the initial hydraulic lateral expansion of magma into an incipient sill, and still have enough input inertial force left to continue feeding the hydraulic system. The lateral expansion underneath the strong impeding layer, causes an area increase and thus, further hydraulic amplification of the input inertial force on the sides and roof of the incipient sill, triggering further expansion in a self-reinforcing process. Initially, the lateral pressure increase is larger than that in the roof allowing the sill to expand. However, expansion eventually increases the total integrated force on the roof allowing its uplift into either a laccolith, if the roof preserves continuity, or into a piston bounded by a circular set of fractures. Hydraulic models for shallow magmatic chambers, also suggest that laccolith-like intrusions require the existence of a self-supported chamber roof. In contrast, if the roof of magmatic chambers loses the self-supporting capacity, lopoliths and calderas should be expected for more or less dense magmas, respectively, owing to the growing influence of the density contrast between the host rock and the magma. 展开更多
关键词 Pascal’s principle GEOLOGIC hydraulic JACK EMPLACEMENT sILLs growth Fluid hammer
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A method to determine relevant geomechanical parameters for evaluating the hydraulic erodibility of rock
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作者 Lamine Boumaiza Ali Saeidi Marco Quirion 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第5期1004-1018,共15页
Among the methods used for evaluating the potential hydraulic erodibility of rock,the most common methods are those based on the correlation between the force of flowing water and the capacity of a rock to resist eros... Among the methods used for evaluating the potential hydraulic erodibility of rock,the most common methods are those based on the correlation between the force of flowing water and the capacity of a rock to resist erosion,such as Annandale’s and Pells’methods.The capacity of a rock to resist erosion is evaluated based on erodibility indices that are determined from specific geomechanical parameters of a rock mass.These indices include unconfined compressive strength(UCS)of rock,rock block size,joint shear strength,a block’s shape and orientation relative to the direction of flow,joint openings,and the nature of the surface to be potentially eroded.However,it is difficult to determine the relevant geomechanical parameters for evaluating the hydraulic erodibility of rock.The assessment of eroded unlined spillways of dams has shown that the capacity of a rock to resist erosion is not accurately evaluated.Using more than 100 case studies,we develop a method to determine the relevant geomechanical parameters for evaluating the hydraulic erodibility of rock in unlined spillways.The UCS of rock is found not to be a relevant parameter for evaluating the hydraulic erodibility of rock.On the other hand,we find that the use of three-dimensional(3D)block volume measurements,instead of the block size factor used in Annandale’s method,improves the rock block size estimation.Furthermore,the parameter representing the effect of a rock block’s shape and orientation relative to the direction of flow,as considered in Pells’method,is more accurate than the parameter adopted by Annandale’s method. 展开更多
关键词 ROCK mass hydraulic ERODIBILITY Geomechanical parameters ROCK block size Annandale’s METHOD Pells’method Kirsten’s index EROsION level
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Revisiting the methods of determining hydraulic conductivity of saturated expansive clays in low-compressibility zone
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作者 Wei Su Yu-Jun Cui +1 位作者 Feng Zhang Weimin Ye 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第5期1131-1136,共6页
The hydraulic conductivity of saturated clays is commonly determined either directly by monitoring water flux or indirectly based on Terzaghi’s consolidation equation.Similar results are generally obtained from the t... The hydraulic conductivity of saturated clays is commonly determined either directly by monitoring water flux or indirectly based on Terzaghi’s consolidation equation.Similar results are generally obtained from the two methods,but sometimes a significant difference can be observed,in particular for expansive soils.In this study,the hydraulic conductivities determined by the two methods are first compared based on existing data in the literature.The indirect method is then revisited attempting to explain the difference identified.A modified effective stress,considering physico-chemical interaction between face-to-face oriented particles,is finally introduced to better describe the compressibility of expansive clays and to further improve the indirect method in determining hydraulic conductivity of such soils in the low-compressibility zone.Extra tests were performed on Gaomiaozi(GMZ)bentonite slurry and the results obtained allowed the modified indirect method to be verified. 展开更多
关键词 Expansive clays Laboratory tests hydraulic conductivity Terzaghi’s consolidation equation Modified effective stress
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Application of Multi-sensor Information Fusion in the Fault Diagnosis of Hydraulic System 被引量:5
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作者 LIU Bao-jie YANG Qing-wen +2 位作者 WU Xiang FANG Shi-dong GUO Feng 《International Journal of Plant Engineering and Management》 2017年第1期12-20,共9页
Aiming at the problem of incomplete information and uncertainties in the diagnosis of complex system by using single parameter, a new method of multi-sensor information fusion fault diagnosis based on BP neural networ... Aiming at the problem of incomplete information and uncertainties in the diagnosis of complex system by using single parameter, a new method of multi-sensor information fusion fault diagnosis based on BP neural network and D-S evidence theory is proposed. In order to simplify the structure of BP neural network, two parallel BP neural networks are used to diagnose the fault data at first; and then, using the evidence theory to fuse the local diagnostic results, the accurate inference of the inaccurate information is realized, and the accurate diagnosis resuh is obtained. The method is applied to the fault diagnosis of the hydraulic driven servo system (HDSS) in a certain type of rocket launcher, which realizes the fault location and diagnosis of the main components of the hydraulic driven servo system, and effectively improves the reliability of the system. 展开更多
关键词 information fusion D-s evidence theory BP neural network fault diagnosis hydraulic system
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Accounting for Quadratic and Cubic Invariants in Continuum Mechanics–An Overview
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作者 Artur V.Dmitrenko Vladislav M.Ovsyannikov 《Fluid Dynamics & Materials Processing》 EI 2024年第9期1925-1939,共15页
The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related fields.These equations contain derivatives of the first ... The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related fields.These equations contain derivatives of the first order with respect to time.The derivation of the equations of continuum mechanics uses the limit transitions of the tendency of the volume increment and the time increment to zero.Derivatives are used to derive the wave equation.The differential wave equation is second order in time.Therefore,increments of volume and increments of time in continuum mechanics should be considered as small but finite quantities for problems of wave formation.This is important for calculating the generation of sound waves and water hammer waves.Therefore,the Euler continuity equation with finite time increments is of interest.The finiteness of the time increment makes it possible to take into account the quadratic and cubic invariants of the strain rate tensor.This is a new branch in hydrodynamics.Quadratic and cubic invariants will be used in differential wave equations of the second and third order in time. 展开更多
关键词 Quadratic invariant cubic invariant continuity equation generation of periodic waves N.E.Zhukovsky’s hydraulic shock TURBULENCE
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基于ABAQUS仿真的水下液压破碎锤凿岩施工参数设计
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作者 陈广云 单丹 《水运工程》 2024年第2期198-202,共5页
针对液压破碎锤水下凿岩施工无法可视化、施工参数难确定的问题,采用ABAQUS仿真平台进行水下液压破碎锤凿岩模拟,对凿岩施工参数设计进行理论研究。不同型号破碎锤的冲击能大小对凿岩速度的影响很大,为获得理想的施工效率,需根据岩石参... 针对液压破碎锤水下凿岩施工无法可视化、施工参数难确定的问题,采用ABAQUS仿真平台进行水下液压破碎锤凿岩模拟,对凿岩施工参数设计进行理论研究。不同型号破碎锤的冲击能大小对凿岩速度的影响很大,为获得理想的施工效率,需根据岩石参数选择破碎锤型号。研究发现3个自由面条件下凿岩产生2个方向的劈裂效果,随着凿岩布孔间距少量增大,凿入深度变化不大,但劈裂效果产生的深度变化较大。对于航道疏浚平整度要求高的情况下,选择凿入深度和产生劈裂效果深度相当的布孔参数,施工效率和施工质量均能达到理想的效果。 展开更多
关键词 液压破碎锤 凿岩 施工参数 ABAQUs软件
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基于T-S模糊故障树的液压旋挖钻机缓冲平衡阀故障诊断方法
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作者 张恒武 章建平 +3 位作者 郭达明 周卓 刘永宽 马小珑 《机械制造与自动化》 2024年第6期268-273,共6页
为了准确、高效地识别液压旋挖钻机缓冲平衡阀故障,提出基于T-S模糊故障树的液压旋挖钻机缓冲平衡阀故障诊断方法。分析液压旋挖钻机缓冲平衡阀结构,建立运动学方程,对其旋挖运动特性展开分析。设计T-S模糊门,根据液压旋挖钻机缓冲平衡... 为了准确、高效地识别液压旋挖钻机缓冲平衡阀故障,提出基于T-S模糊故障树的液压旋挖钻机缓冲平衡阀故障诊断方法。分析液压旋挖钻机缓冲平衡阀结构,建立运动学方程,对其旋挖运动特性展开分析。设计T-S模糊门,根据液压旋挖钻机缓冲平衡阀现场的故障数据,结合专家经验,在平衡阀旋挖动力特点的基础上建立T-S模糊故障树,将缓冲阀状态异常作为故障树的顶层事件。利用T-S模型得到故障事件的故障程度,实现液压旋挖钻机缓冲平衡阀的故障诊断。实验结果表明:所提方法诊断效率高、诊断精度高。 展开更多
关键词 液压旋挖钻机 缓冲平衡阀 T-s模糊故障树 故障诊断
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垂直管道水力输送的水击研究与AMESim仿真分析 被引量:8
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作者 李艳 蒋坤 唐达生 《广西大学学报(自然科学版)》 CAS 北大核心 2015年第2期412-420,共9页
为降低深海采矿中矿物垂直水力提升中的水击现象,根据垂直管固液两相流的特征,考虑固液两相流密度、浓度、弹性模量等特点,对垂直管水力提升不稳定流开展研究。推导出粗颗粒—匀质浆体两相流提升水击压力波波速方程、连续方程和运动方程... 为降低深海采矿中矿物垂直水力提升中的水击现象,根据垂直管固液两相流的特征,考虑固液两相流密度、浓度、弹性模量等特点,对垂直管水力提升不稳定流开展研究。推导出粗颗粒—匀质浆体两相流提升水击压力波波速方程、连续方程和运动方程,并且基于AMESim软件搭建了垂直管道水击仿真模型。分析了不同管道长度、不同管道直径以及不同颗粒浓度下的水击特性。仿真结果表明:每增加18 m管道长度,平均可以降低约12%的压力峰值,同时减小压力波对管道壁的冲击;每增加10 mm管道直径,也可以降低约7%的压力峰值,但流速增加,紊流强度增大;粗颗粒浓度每增加6%,压力峰值相应增加约2%,与此同时对管道壁的冲击也增加。研究方法及结论对于实际深海采矿中的垂直管道提升具有指导借鉴意义。 展开更多
关键词 水力提升 水击 粗颗粒 AMEsIM
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3SFBQ-500型果园气爆松土注肥机的优化设计与试验 被引量:14
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作者 奚小波 张瑞宏 +2 位作者 单翔 金亦富 张剑峰 《农业工程学报》 EI CAS CSCD 北大核心 2017年第24期35-43,共9页
针对目前果园开沟施肥存在的易伤树木根系、耕作能耗大、施肥不均等问题,该文研制了3SFBQ-500型果园气爆松土注肥机,采用液力辅助气铲激振的钻杆结构,建立液力辅助气铲钻土的力学模型及运动学方程,分析了钻杆的土力学关系,优化了钻头构... 针对目前果园开沟施肥存在的易伤树木根系、耕作能耗大、施肥不均等问题,该文研制了3SFBQ-500型果园气爆松土注肥机,采用液力辅助气铲激振的钻杆结构,建立液力辅助气铲钻土的力学模型及运动学方程,分析了钻杆的土力学关系,优化了钻头构型参数,优化后的钻头锥角60°、钻杆圆柱半径12.5 mm;设计了一种基于PLC控制的经济型多旋钮式开关操控系统,实现了机具手动、自动控制作业,一键操作可完成钻杆钻土、气爆松土、液肥注射、钻杆回升四步操作;在SolidWorks软件中建立了样机模型,并完成了样机的试制与田间试验工作。样机田间试验结果表明,气爆作用可在土体内部产生裂隙并扩散,300 mm钻深、0.8 MPa气爆压力下的土体最大裂隙宽约3~4 mm,裂隙扩展扰动半径约400 mm;土壤在气爆下发生扰动,扰动系数达50.11%;液肥在注肥机构作用下可在深土层中无堵塞喷射,并均匀扩散;样机操作简便,运行稳定,工作效率至少0.048 hm^2/h,满足果园施液肥农艺要求,适用于果树、园林、绿化地的施肥作业。 展开更多
关键词 优化 设计 农业机械 气爆松土 注肥 气铲激振 液力辅助 PLC
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基于AMESim的液压破碎锤液压系统建模与仿真 被引量:20
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作者 司癸卯 张青兰 +2 位作者 段立立 李晓宁 孙恒 《中国工程机械学报》 2010年第2期179-183,共5页
介绍了仿真软件AMESim的特点,利用AMESim仿真软件对液压破碎锤液压系统进行建模和仿真,分析了其工作参数对液压锤性能的影响,通过调节频率得到液压锤最优参数.仿真结果为以后液压锤的工程应用提供了理论参考.
关键词 液压破碎锤 液压系统 AMEsIM 建模与仿真
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