High-end equipment always operate in low-speed and heavy-load working environments,highlighting the need for cam-lobe hydraulic motors with excellent speed stability(<1 r/min)and ultrahigh-power rotary output(>1...High-end equipment always operate in low-speed and heavy-load working environments,highlighting the need for cam-lobe hydraulic motors with excellent speed stability(<1 r/min)and ultrahigh-power rotary output(>1 MW).The successful operation of cam-lobe hydraulic motors relies on the circulation supply of high-and low-pressure oil.However,the switching between high-/low-pressure oil controlled by the oil distributor inevitably causes an obvious pressure impact and speed pulsation,which directly reduces the speed stability of hydraulic motors.Therefore,an optimization design approach for the oil distributor port is proposed to minimize the speed pulsation of cam-lobe hydraulic motors.In the proposed approach,a simulation model that links the oil distributor port structural parameters with the hydraulic motor speed pulsation was developed to clarify the e ect of the oil distributor structural parameters on speed pulsation.Then,an orthogonal analysis method was used to identify the optimized oil distributor port structural parameters while minimizing the hydraulic motor's speed pulsation as much as possible.Finally,several experiments were conducted to validate the e ectiveness and accuracy of the proposed optimization design approach.The experimental results indicate that the pulsation rate of the hydraulic motor equipped with the optimized oil distributor was 62.5%lower than that of the original motor at a working pressure of 25 MPa,which is consistent with the simulation results using the proposed optimization design approach.The findings of this study o er a feasible and e ective approach to guide the design optimization of the oil distributor port for low-pulsation hydraulic motors.展开更多
粮食的储藏安全对于国家降低粮食供给波动、改善人民生活、促进社会稳定等方面具有重要作用,研究进料方式造成的孔隙率分布特征对通风降温效果的影响,对保证粮食安全具有重大意义。文章针对装配了新型螺旋进料器的浅圆仓,使用离散元方法...粮食的储藏安全对于国家降低粮食供给波动、改善人民生活、促进社会稳定等方面具有重要作用,研究进料方式造成的孔隙率分布特征对通风降温效果的影响,对保证粮食安全具有重大意义。文章针对装配了新型螺旋进料器的浅圆仓,使用离散元方法(Discrete Element Method, DEM)模拟该进料装置的装粮过程,重构了粮堆多孔结构;通过提取堆积体内颗粒位置分布信息分析静态粮堆内部孔隙率的分布规律。结果表明:配备螺旋布料装置的浅圆仓内粮堆具有更均匀的颗粒分布,且孔隙率分布跨度较小,能够显著地降低粮食颗粒的自动分级现象。展开更多
基金Supported by National Key R&D Program of China(Grant No.2021YFB3400501)。
文摘High-end equipment always operate in low-speed and heavy-load working environments,highlighting the need for cam-lobe hydraulic motors with excellent speed stability(<1 r/min)and ultrahigh-power rotary output(>1 MW).The successful operation of cam-lobe hydraulic motors relies on the circulation supply of high-and low-pressure oil.However,the switching between high-/low-pressure oil controlled by the oil distributor inevitably causes an obvious pressure impact and speed pulsation,which directly reduces the speed stability of hydraulic motors.Therefore,an optimization design approach for the oil distributor port is proposed to minimize the speed pulsation of cam-lobe hydraulic motors.In the proposed approach,a simulation model that links the oil distributor port structural parameters with the hydraulic motor speed pulsation was developed to clarify the e ect of the oil distributor structural parameters on speed pulsation.Then,an orthogonal analysis method was used to identify the optimized oil distributor port structural parameters while minimizing the hydraulic motor's speed pulsation as much as possible.Finally,several experiments were conducted to validate the e ectiveness and accuracy of the proposed optimization design approach.The experimental results indicate that the pulsation rate of the hydraulic motor equipped with the optimized oil distributor was 62.5%lower than that of the original motor at a working pressure of 25 MPa,which is consistent with the simulation results using the proposed optimization design approach.The findings of this study o er a feasible and e ective approach to guide the design optimization of the oil distributor port for low-pulsation hydraulic motors.
文摘粮食的储藏安全对于国家降低粮食供给波动、改善人民生活、促进社会稳定等方面具有重要作用,研究进料方式造成的孔隙率分布特征对通风降温效果的影响,对保证粮食安全具有重大意义。文章针对装配了新型螺旋进料器的浅圆仓,使用离散元方法(Discrete Element Method, DEM)模拟该进料装置的装粮过程,重构了粮堆多孔结构;通过提取堆积体内颗粒位置分布信息分析静态粮堆内部孔隙率的分布规律。结果表明:配备螺旋布料装置的浅圆仓内粮堆具有更均匀的颗粒分布,且孔隙率分布跨度较小,能够显著地降低粮食颗粒的自动分级现象。
