The oil outflow condition in the spool valve with U shaped notches was analyzed as an example in order to obtain the flow forces characteristics of the non-circular opening spool valve in spool movement process under such conditions as different spool speed, direction of movement, pressure differential and throttle slot numbers. The non-conformal, sliding mesh techniques and UDF programming method were adopted. Numerical results show that there is only marginal difference between the flow forces obtained from steady and transient calculations when the spool speed is below 0.1 m/s, so transient calculation can be approximately used in place of steady state calculation. The deviation between these two simulation results became more obvious with the increase of spool speed. The flow force hysteresis appeared when the spool motion direction changed. Flow force redirection happened when the spool approaching to small valve opening with big speed in closing movement. The hysteresis became more obvious with the addition of spool speed, pressure differential and throttling groove number.
WANG Jian sen, LIU Yao lin, JI Hong, WANG Peng fei. Transient simulation on flow force of non-circular opening spool valve. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2016, 50(10): 1922-1926.
［1］ 冀宏,傅新,杨华勇.非全周开口滑阀稳态液动力研究［J］.机械工程学报,2003, 39(6): 13-17.
JI Hong, FU Xin, YANG Huayong. Study on steady flow force of noncircular opening spool valve ［J］. Chinese Journal of Mechanical Engineering, 2003, 39(6):13-17.
［2］ AMIRANTE R, DEL VESCOVO G, LIPPOLIS A. Flow forces analysis of an open center hydraulic directional control valve sliding spool ［J］. Energy Conversion and Management, 2006, 47(1): 114-131.
［3］ AMIRANTE R, MOSCATELLI P G, CATALANO L A. Evaluation of the flow forces on a direct (single stage) proportional valve by means of a computational fluid dynamic analysis ［J］. Energy Conversion and Management, 2007, 48(3): 942-953.
［4］方文敏,成琳琳,傅新,等.带U形节流槽的滑阀稳态液动力研究［J］.浙江大学学报：工学版,2010, 44(3):574-580.
FANG Wenmin, CHENG Linlin, FU Xin, et al. Investigation on steady state flow force of spool valve with Ugrooves ［J］. Journal of Zhejiang University: Engineering Science, 2010, 44(3): 574-580.
［5］ 吴晓明,要继业,李伟,等.U+K节流槽滑阀的数值模拟［J］.流体传动与控制,2010, 5: 13-16.
WU Xiaoming, YAO Jiye, LI Wei, et al. The numerical simualtion of spool valve with U+K notches ［J］. Fluid Power Transmission and Control, 2010, 5: 13-16.
［6］ 高俊庭,殷晨波,叶仪,等.非全周开口的液压滑阀内部流场的CFD解析［J］.液压与气动,2013, 5: 58-61.
GAO Junting, YIN Chenbo, YE Yi, et al. CFD simulation of flow field in hydraulic spool valve with notches ［J］. Chinese Hydraulic and Pneumatics, 2013, 5: 58-61.
［7］ 叶仪,殷晨波,刘辉,等.节流槽阀口静态流动特性研究［J］.农业机械学报,2014, 45(6): 308-316.
YE Yi, YIN Chenbo, LIU Hui, et al. Stationary flow characteristics of notches on throttling grooves ［J］. Transaction of the Chinese Society for Agricultural Machinery, 2014, 45(6)：308-316.
［8］ DEL VESCOVO G, LIPPOLIS A. Review analysis of unsteady forces in hydraulic valves ［J］. International Journal of Fluid Power, 2006, 7(3): 29-39.
［9］ 赵蕾,陈青,权龙.阀芯运动状态滑阀内部流场的可视化分析［J］.农业机械学报,2008,39(11): 142-146.
ZHAO Lei, CHEN Qing, QUAN Long. Visualizaion of the flow field in a moving spool valve ［J］.Transaction of the Chinese Society for Agricultural Machinery, 2008,39(11): 142-146.
［10］ POSA A, ORESTA P, LIPPOLIS A. Influence of the spool velocity on the performance of a directionalhydraulic valve ［J］. International Journal of Fluid Power, 2013, 14(3): 15-25.
［11］ 王东升.节流槽滑阀阀口流量系数及稳态液动力计算的研究［D］.兰州:兰州理工大学,2008: 42-43.
WANG Dongsheng. Investigation into flow coefficient of orifice and caculation of steady flow force of spool valve with notches ［D］. Lanzhou: Lanzhou University of Technology, 2008: 42-43.
［12］ 冀宏,侯敏,王金林,等. 液动多路阀主阀芯瞬态运动的实测［J］.机床与液压,2011, 39(23): 69.
JI Hong, HOU Min, WANG Jinlin, et al. Measurement of dynamic motion of spool in hydraulic operated mutiway valve ［J］. Machine Tool and Hydraulics, 2011, 39(23): 69.
