Research on Hydraulic System of Hydraulic Driven Garden Pulverizer Based on AMESim Simulation

To analyze a certain type of trees crusher working condition, to consider the limitation of electric, the motor driven pulverizer can only work in a fixed place. Therefore, a set of hydraulic system is used to replace the motor. So it can get rid of electricity, and move conveniently, applying to the suburbs, parks, roadsides, which means expanding the range of application. Secondly, in view of the pulverizer speed higher than the motor speed, it is necessary to add the auxiliary speed regulating device. Besides , to adjust speed is more troublesome, and the hydraulic motor can directly drive the pulverizer. Therefore to adjust the flow of the hydraulic motor can change the speed of the pulverizer. In addition, base on the characteristics of work start, and stop, with a long time, big moment of inertia for Pulverizer, and it is the growth process of the motor driving pulverizer. The rotary inertia equivalent to the motor end will increase the square of the reduce ratio, and the load of the machine obviously. Driving by hydraulic motor straightly, and this problem will be avoided. Finally, in the light of the large start-up torque, and the high speed at working time of the pulverizer, the constant power pumps is choosed to meet the work demand. Constant power pumps can adjust the flow and pressure according to the different load automatically, thus more energy are saved. Hydraulic system simulation model is established based on the AMESim simulation, which verify the scheme is feasible

基于Simcenter AMEsim与Matlab联合仿真的电液控制伺服系统模拟实验设计

针对传统液压油缸控制伺服系统模型的复杂可变性、系统参数不确定性和时变性等,设计一种基于Simcenter Amesim-Matlab联合仿真的电液位置伺服系统仿真模拟实验。以常规液压缸为实验设计对象,利用Matlab与Simcenter AMESim软件对电液伺服系统的模型辨识方法进行设计;基于相关传递函数,进行滑膜变结构控制器设计;将其应用到特定的变载荷条件下的恒速电液位置伺服系统实验仿真。仿真结果表明,该方法具有良好的实用性与有效性。该模拟实验仿真的开展可加深学生对电液位置伺服系统理论知识的理解,提升学生的综合运用能力。

Numerical analysis of hydraulic fracture propagation in deep shale reservoir with different injection strategies

Deep shale reservoirs are characterized by elevated breakdown pressures,diminished fracture complexity,and reduced modified volumes compared to medium and shallow reservoirs.Therefore,it is urgent to investigate particular injection strategies that can optimize breakdown pressure and fracturing efficiency to address the increasing demands for deep shale reservoir stimulation.In this study,the efficiency of various stimulation strategies,including multi-cluster simultaneous fracturing,modified alternating fracturing,alternating shut-in fracturing,and cyclic alternating fracturing,was evaluated.Subsequently,the sensitivity of factors such as the cycle index,shut-in time,cluster spacing,and horizontal permeability was investigated.Additionally,the flow distribution effect within the wellbore was discussed.The results indicate that relative to multi-cluster simultaneous fracturing,modified alternating fracturing exhibits reduced susceptibility to the stress shadow effect,which results in earlier breakdown,extended hydraulic fracture lengths,and more consistent propagation despite an increase in breakdown pressure.The alternating shut-in fracturing benefits the increase of fracture length,which is closely related to the shut-in time.Furthermore,cyclic alternating fracturing markedly lowers breakdown pressure and contributes to uniform fracture propagation,in which the cycle count plays an important role.Modified alternating fracturing demonstrates insensitivity to variations in cluster spacing,whereas horizontal permeability is a critical factor affecting fracture length.The wellbore effect restrains the accumulation of pressure and flow near the perforation,delaying the initiation of hydraulic fractures.The simulation results can provide valuable numerical insights for optimizing injection strategies for deep shale hydraulic fracturing.

Simulation Method and Feature Analysis of Shutdown Pressure Evolution During Multi-Cluster Fracturing Stimulation

Multistage multi-cluster hydraulic fracturing has enabled the economic exploitation of shale reservoirs,but the interpretation of hydraulic fracture parameters is challenging.The pressure signals after pump shutdown are influenced by hydraulic fractures,which can reflect the geometric features of hydraulic fracture.The shutdown pressure can be used to interpret the hydraulic fracture parameters in a real-time and cost-effective manner.In this paper,a mathematical model for shutdown pressure evolution is developed considering the effects of wellbore friction,perforation friction and fluid loss in fractures.An efficient numerical simulation method is established by using the method of characteristics.Based on this method,the impacts of fracture half-length,fracture height,opened cluster and perforation number,and filtration coefficient on the evolution of shutdown pressure are analyzed.The results indicate that a larger fracture half-length may hasten the decay of shutdown pressure,while a larger fracture height can slow down the decay of shutdown pressure.A smaller number of opened clusters and perforations can significantly increase the perforation friction and decrease the overall level of shutdown pressure.A larger filtration coefficient may accelerate the fluid filtration in the fracture and hasten the drop of the shutdown pressure.The simulation method of shutdown pressure,as well as the analysis results,has important implications for the interpretation of hydraulic fracture parameters.

Dynamic impact experiment and response characteristics analysis for 1:2 reduced-scale model of hydraulic support

It is significant to research the impact resistance properties of hydraulic support due to its key support role in the fully mechanized mining face.However,it is difficult for the entire hydraulic support to implement the impact experiment underground and analyze the response characteristic.Therefore,a dynamic impact experiment for the entire hydraulic support was proposed in this paper,where a 1:2 reducedscale model of hydraulic support was designed and its response characteristics under dynamic impact load were analyzed.Firstly,a comprehensive monitoring scheme was proposed to achieve an effective monitoring for dynamic response of hydraulic support.Secondly,a multi-scale impact experiment was carried out for the entire hydraulic support and dynamic behaviors of hydraulic support under the multi-scale impact load were revealed by experimental data.Then a dynamic impact experiment of the entire hydraulic support was simulated in ADAMS with the same experiment conditions,and the experimental and simulation data were verified mutually.Finally,the characteristics of energy conversion and dissipation of the entire experiment system after impact were analyzed.The experiment results showed that the impact resistance properties of hydraulic support largely depended on the initial support conditions and different vertical rigidities affected energy distribution proportion of the entire support system.

Dynamic Performance Analysis of Gas-Liquid United Hydraulic Hammer

In order to improve the impactor performance, the dynamic performance of gas-liquid united hydraulic hammer should be optimized. Based on the analysis of the operating principle for the hydraulic impactor, one simulation model of gas-liquid united hydraulic impactor was built with AMESim software. By setting different simulation parameters, curves of displacement, velocity, acceleration and cavity pressure were obtained under different working conditions. The key component can be obtained by the analysis of activity index. The whole simulation results provide a reliable basis for component selection and parameter optimization of hydraulic impactor.

Research of refrigeration system for a new type of constant temperature hydraulic tank

Different from the traditional hydraulic oil cooling method,a new type of constant temperature oil tank cooling system based on semiconductor refrigeration technology is designed. This paper studies the principle of semiconductor refrigeration and establishes a heat transfer model. Semiconductor cooler on piping refrigeration is simulated,and influence of the parameters on the outlet temperature,such as pipe pressure difference of inlet and outlet,pipe length,pipe radius,are gotten,and then hydraulic tank semiconductor refrigeration system is proposed. The semiconductor refrigeration system can control temperature at 37 ± 1°C.

Methanol Distillation System: Process Analysis and Column Design

Base on industrial research and experience, the process of methanol distillation is analyzed,and above all, a new concept of high pressure flowsheet and low pressure flowsheet is defined. The new configuration helps to handle problems encountered in many factories in China. The inter influence between process and column internal pattern is also pointed out. Recommendation of new column internal designs is given. Finally, industrial examples tell the how the new concept works and the possibility of combining process to give more opens to solve engineering problems.

Model identification of hydraulic flight simulator based on improved particle swarm optimization and wavelet analysis

A new model identification method of hydraulic flight simulator adopting improved panicle swarm optimization （PSO） and wavelet analysis is proposed for achieving higher identification precision. Input-output data of hydraulic flight simulator were decomposed by wavelet muhiresolution to get the information of different frequency bands. The reconstructed input-output data were used to build the model of hydraulic flight simulator with improved particle swarm optimization with mutation （IPSOM） to avoid the premature convergence of traditional optimization techniques effectively. Simulation results show that the proposed method is more precise than traditional system identification methods in operating frequency bands because of the consideration of design index of control system for identification.

基于AMESim的电磁换向阀高温可靠性试验台故障分析与诊断

针对客机系统电磁换向阀的故障情况,使用AMESim仿真软件搭建了电磁换向阀高温可靠性试验台的仿真模型。通过设置能表示元件失效的参数如电磁铁烧毁、弹簧折断、推杆磨损、内泄漏、迟滞等以模拟电磁换向阀的部分故障情况。同时对高温时内泄漏量的变化以及高温时推杆磨损对流量的影响进行了仿真。仿真结果表明:随着温度的升高,引起换向阀的流量变化所对应的推杆磨损量逐渐增大。此外,油液泄漏量受温度影响较大,应注意阀的加工精度、配合精度以避免较大的泄漏。仿真结果为试验台的调试以及实际使用过程中的故障诊断提供了参考。

基于AMESim的圆柱桥墩浇筑模具液压系统设计与研究

针对当前预制桥墩浇筑过程中模具的对接、调平、内部清洗以及脱模等工作难以通过人力完成的问题,设计一套圆柱桥墩浇筑模具工作液压系统。通过分析模具工作要求,采用多路阀控制整个液压系统,实现不同执行元件的复合运动要求。建立AMESim仿真模型并进行分析,得到液压缸在不同C v值下的动态特性曲线,并根据仿真结果对液压系统进行实验验证。结果表明:额定压力设定为16 MPa时,该液压系统能满足实际工作的负载要求,还能提供足够压力保证液压缸的速度和行程要求;系统C v值设定为0.3~0.7时,满足系统变速要求且速度波动小;仿真结果与实验结果基本相符,验证了液压系统的有效性。

Analysis on Static Pressure Bearing Seal Characteristics of Guide Sleeve of Electro-hydraulic Servo Cylinder

As a typical bionic walking robot, hydraulic quadruped robot has attracted much attention because of its high mobility, strong load capacity and steady motion. The electro-hydraulic servo cylinder, as its power actuator, requires low friction, good lateral load resistance and high speed motion. The electro-hydraulic servo cylinder hydrostatic bearing seal guide sleeve is taken as the research object in this paper. By using Fluent software to analyze and contrast the film characteristics of rectangular and I-shaped oil chamber of hydrostatic bearing seal guide sleeve, the relationship between piston rod moving speed, eccentricity, oil film carrying capacity, friction force and leakage volume, as well as the relationship between oil feed flow and oil film bearing capacity, friction force, inlet pressure and leakage volume were analyzed. This study provides a theoretical basis for optimizing the static pressure bearing seal parameters.

基于AMESim新型径向柱塞泵设计与性能分析

基于传统径向柱塞泵的结构,通过改变转子与定子的布置方式,设计了一种新型径向柱塞泵。首先,阐述了新型径向柱塞泵的结构和工作原理,利用AMESim软件分析了其流量和压力特性,并与传统径向柱塞泵进行了比较;然后分析了不同参数对新型柱塞泵性能的影响。分析结果表明:与传统径向柱塞泵相比,新型径向柱塞泵流量波动平缓、脉动小,压力特性优于传统径向柱塞泵;增大外负载,泵的输出流量基本保持稳定;增大柱塞数能有效降低流量脉动;柱塞直径和偏心距越大,柱塞泵流量曲线波动幅值越大。

基于AMESim的压力加油控制阀的性能研究

压力加油控制阀采用两套相互独立的控制措施,实现压力加油双余度切断功能,其安装于油箱底部,利用该加油控制阀进行压力加油时,当油液达到相应高度时切断加油。为了研究该压力加油控制阀的工作性能,依据其实际结构改变节流孔大小对其加油过程进行分析。首先建立压力加油控制阀数学模型并结合物理模型进行定性分析;再利用AMESim建立仿真模型,通过仿真数据分析不同参数对压力加油控制阀切断时间的影响;最后通过试验验证仿真结果的可靠性。仿真分析结果表明:节流孔大小对压力加油控制阀切断性能有很大影响;调整节流孔大小可显著优化压力加油控制阀的切断时间。

基于AMESim的能源冗余电液伺服系统建模及故障模拟仿真

针对一种应用于航天领域的能源冗余电液伺服系统,建立了从溢流阀、限流阀、能源选择阀等关键阀门元件到伺服系统的AMESim仿真模型并进行仿真分析,仿真结果与理论设计结果相符。建立双机互联冗余伺服系统仿真模型,对一路溢流阀失效无法建压的典型故障模式进行模拟仿真。结果表明:在该情况下能源选择阀发生了切换,引入另一路能源为伺服机构供油,保证整个系统正常工作,验证了伺服系统能源冗余切换功能原理的正确性。建立的仿真模型具有实际参考价值,也能用于其他故障失效模式下的仿真分析。

基于AMEsim的液压惯容器外特性仿真分析

为分析影响液压式惯容器的力学性能的关键参数,在AMEsim软件中搭建仿真模型,并进行参数设置。通过仿真分析油液的粘度、液压管道参数、液压马达排量、飞轮转动惯量、活塞杆直径等参数对于液压惯容器的外特性的影响。仿真结果表明:阻尼力不容忽略,管道直径、管道长度、液压马达、飞轮转动惯量以及活塞杆直径的变化对其外特性的影响较大。

基于AMESim的大型磨齿机静压支承转台特性研究

为提升大型数控磨齿机的加工精度,研究了磨齿机静压支承转台的整体结构和工况以及分析了求解油膜厚度和输出流量的理论模型,初步得出了偏载对油膜厚度具有较大影响。为了进一步验证,在分析现有参数设计方法的基础上,利用AMESim软件建立系统模型,对不同工况和结构参数进行系统动态仿真分析。仿真结果表明:静压支承转台结构参数可以保证转台产生足够的承载力,流量脉动对油膜厚度变化率的影响不到0.4%,偏载对油膜厚度变化率的影响最大为13%,静态和动态仿真结果均与实际数据相符,性能测试结果满足磨床设计要求。

基于AMESim的叉车液压提升系统仿真分析

为了解决电动叉车货叉持重时液压缸回缩速度过快而产生较大冲击,容易损伤缸体和管路以及货叉持重量不同时液压缸伸出速度不可控的问题,优化了电动叉车液压提升系统,并进行仿真验证。根据设计手册设计液压提升系统,初选系统工作压力为16 MPa,在液压泵的出油路上连接蓄能器来吸收流量脉动,在液压缸无杆腔进油路配置调速阀,实现了对不同持重量的压力补偿,使抬升速度可控,在无杆腔回油路上配置顺序阀,为液压缸活塞杆在承载回缩时提供给背压,避免活塞杆自由下落损伤液压缸;对液压元件进行了设计选型,选用CBG2100-BF100液压泵、HSGL-100/70E-231-3000×3280液压缸、3WE10E31B/CG24N9Z4电磁换向阀、RVP30-10B单向阀、DBDS30P10B顺序阀和THF-G10调速阀;应用功率键和图的原理对液压系统进行研究,使用数字仿真法研究液压系统的动态特性,通过仿真软件AMESim搭建液压系统数学模型,并对设置关键元件参数进行仿真。仿真结果表明,优化后液压系统的液压缸活塞杆完全缩回用时8 s,无振荡,运行稳定,液压缸活塞杆缩回时油口流量为87 L/min,液压泵产生的流量脉动被蓄能器吸收,系统运行稳定,符合设计要求,液压提升系统理论上可行、可靠。

基于AMESim的隔水管下部总成液压控制系统仿真研究

基于对隔水管下部总成不同工况的分析,对其液压控制系统内的续油管剪切闸板、钢丝剪切阀及延时驱动装置等关键元器件进行AMESim建模后分析,并针对不同工况对液压控制系统进行仿真研究。利用AMESim平台进行机械、电器、液压联合仿真,分析研究匹配参数,从而验证液压控制系统配置能完整完成“首次脱离-回接-二次脱离”的工作任务,为隔水管下部总成液压控制系统的工程开发提供了理论指导。