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双泵合流系统电-液联控合流阀设计与试验 被引量:2
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作者 李明生 叶进 +3 位作者 谢斌 杨仕 曾百功 柳剑 《农业机械学报》 EI CAS CSCD 北大核心 2018年第9期353-360,共8页
设计了一种电-液联控合流阀,电磁阀和换向阀内反馈压力联合控制合流阀的开启和关闭,能够实现油液的双向流动,使流量调速区间更大,执行机构动作更为迅速。基于传统方法确定阀结构参数,设计U型过渡节流槽,在Matlab中建立通流面积模型并进... 设计了一种电-液联控合流阀,电磁阀和换向阀内反馈压力联合控制合流阀的开启和关闭,能够实现油液的双向流动,使流量调速区间更大,执行机构动作更为迅速。基于传统方法确定阀结构参数,设计U型过渡节流槽,在Matlab中建立通流面积模型并进行计算。建立电-液联控合流阀AMESim模型并进行性能仿真,仿真结果表明,该阀控制流量范围为0~5.83×10^(-3)m^3/s,流量变化平稳;在8~11.5 mm阀芯位移区间内,合流阀压力损失随阀口开度增加而降低,当阀芯位移为11.5 mm时,合流阀压力损失为0.18 MPa。起重机卷扬系统试验结果表明,该阀最大流量达6×10^(-3)m^3/s,最大流量下压力损失为0.27 MPa;单泵供油模式下卷扬起升工况,卷筒最低稳定微动速度为1.9 r/min,启动冲击为2.1 MPa,停止冲击为2.2 MPa,启动响应延时0.7 s,停止响应延时0.8 s;卷扬下落工况,卷筒最低稳定微动速度为2.17 r/min,启动冲击为5.2 MPa,停止冲击为1.9 MPa,启动响应延时1.1 s,停止响应延时0.75 s。安装有该阀的双泵合流系统供油时,卷扬起升工况,卷筒最低稳定微动速度为2.17 r/min,启动冲击为2.5 MPa,停止冲击为0 MPa,启动响应延时0.65 s,停止响应延时0.28 s;卷扬下落工况,卷筒最低稳定微动速度为1.57 r/min,启动冲击为2.7 MPa,停止冲击为1.6 MPa,启动响应延时0.57 s,停止响应延时0.31 s。 展开更多
关键词 合流阀 电-液联控 设计 仿真 试验
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液压挖掘机合流阀的控制算法研究
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作者 张振宇 《建筑机械化》 2021年第11期11-13,共3页
合流阀在挖掘机液压控制系统起到流量分配的作用,合流阀的控制对提高整机性能至关重要。本文根据一种挖掘机控制系统所用到电控合流阀的特性参数表,分析了该电控合流阀的特点,提出了基于三点平面拟合法和多层感知器神经网络算法,阐述了... 合流阀在挖掘机液压控制系统起到流量分配的作用,合流阀的控制对提高整机性能至关重要。本文根据一种挖掘机控制系统所用到电控合流阀的特性参数表,分析了该电控合流阀的特点,提出了基于三点平面拟合法和多层感知器神经网络算法,阐述了两种算法的实现原理,比较了两种算法的优缺点。 展开更多
关键词 挖掘机 合流阀 控制策略 多层感知器 神经网络
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Mixed refrigerant composition shift due to throttle valves opening in auto cascade refrigeration system 被引量:5
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作者 许雄文 刘金平 曹乐 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期199-204,共6页
Auto cascade refrigeration(ACR) cycle with phase separators is widely used in the cryogenic system. The composition of mixed refrigerant has a great effect on the performance of the system. Based on the assumption of ... Auto cascade refrigeration(ACR) cycle with phase separators is widely used in the cryogenic system. The composition of mixed refrigerant has a great effect on the performance of the system. Based on the assumption of infinite volume of phase separator, ACR system with one phase separator is simulated in this paper. The variation of refrigerant composition under different valves opening is obtained. A related experimental system is set up to verify the variation. The result shows that when the valve opening connected to the evaporator increases or the valve opening under the phase separator decreases, the low-boiling component concentration of the working mixture passing through the compressor and condenser increases, while the high-boiling component concentration decreases. Furthermore, the variations of condensation pressure and evaporation pressure under different valves opening are also observed. This paper is helpful to deepen the understanding of ACR system. 展开更多
关键词 Auto cascade REFRIGERATION Composition shift THROTTLE
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Methodology for expressing the flow coefficients of coupled throttling grooves in a proportional–directional valve 被引量:8
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作者 Xiao-lu ZHANG An-lin WANG +2 位作者 Wei CHEN Long KUANG Tao JIANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2020年第10期799-816,共18页
Calculating the flow coefficient of a spool-valve is complicated due to the coupling–throttling effect in the throttling grooves of a proportional–directional valve.In this paper,a methodology for expressing the flo... Calculating the flow coefficient of a spool-valve is complicated due to the coupling–throttling effect in the throttling grooves of a proportional–directional valve.In this paper,a methodology for expressing the flow coefficient of coupled throttling grooves is proposed to resolve that difficulty.With this purpose,an approach of a 3 D numerical simulation and an experimental bench were introduced based on the prototype of a commercial proportional valve.The results show consistency between the numerical simulation and the bench test.Based on that,the concept of‘saturation limit’is introduced to describe the value gap between the current and saturated flows,so that the flow-coefficient saturation limit of the prototype in the process can be deducted.Accordingly,an approximate flow coefficient suitable for coupled throttling grooves within finite variable space,which is based on three typical throttling structures(i.e.O-shape,U-shape,and C-shape)of the coupled throttling grooves,is obtained based on an orthogonal test.The model results are consistent with the numerical and experimental results,with maximum errors of less than 5.29%and 5.34%,respectively.This suggests that the proposed method is effective in approximating the flow coefficient. 展开更多
关键词 Flow coefficient Proportional–directional valve Coupled throttling grooves Saturated flow
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Design and integrated simulation of a pressurized feed system of the dual-thrust hybrid rocket motor 被引量:9
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作者 LI JunHai YU NanJia +1 位作者 ZENG Peng CAI GuoBiao 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第4期989-1000,共12页
A new pressurized feed system of the dual-thrust hybrid rocket motor for flight is presented in this paper.The feed system supplies 90% hydrogen peroxide (90%H 2 O 2) with two different flows of 4.5 and 2 kg s 1.The o... A new pressurized feed system of the dual-thrust hybrid rocket motor for flight is presented in this paper.The feed system supplies 90% hydrogen peroxide (90%H 2 O 2) with two different flows of 4.5 and 2 kg s 1.The oxidizer flow is changed through regulating the mass flow of the high-pressure gas and switching the performance modes of the unique oxidizer flow control valve simultaneously.The models of the gas storage container,pressure regulator valve,control orifice,propellant tank,oxidizer flow control valve and cavitating venturi are generated and used to compute the instantaneous pressure,temperature and mass flow rate.There is a good agreement between the simulated and experimental results.Parameter sensitivity analysis is also conducted.It is found that the throat diameter of the cavitating venturi in feed line 1 is the main factor affecting the mass flow in both boost and sustaining phase.Other parameters have limited effects on the mass flow rate and the transition time of the system. 展开更多
关键词 pressurized feed system mathematical modeling liquid propellant tank variable flow dual-thrust hybrid motor
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