簧上质量对油气弹簧阀系设计参数的影响

利用开阀压力和流量以及阀片变形之间的关系，分别建立了油气弹簧节流缝隙和单片节流阀片厚度与单轮簧上质量之间的关系式。在此基础上，对单轮簧上质量对阀系设计参数的影响因素进行了分析，求取了单轮簧上质量影响系数。通过实例，分别利用解析设计法与质量影响系数推算设计方法，对油气弹簧阀系参数进行了设计，对参数设计结果进行了比较和校核，并对设计的油气弹簧进行了特性试验。设计和试验结果表明，单轮簧上质量对油气弹簧阀系设计参数有影响，阀系参数的质量影响系数推算设计方法是可靠的。

Analysis on Jet Stability of Magnetorheological Jet Polishing

In magnetorheological jet polishing(MJP),the stable and collimated jet of magnetorheological(MR) fluid magnetized by a local axial magnetic field near the exit of the nozzle was used to polish the remote surface in a deterministic precision process. But the theoretical considerations on the mechanism of jet stabilization were required for optimization of the technology.Therefore,the stabilization of MR jet under the external axial magnetic field was analyzed.Firstly,a kinematic model was developed to analyze the MR effects on the jet flow.Secondly,the stabilization of MR effect was numerically simulated by finite element methods based on the Maxwell equations and the kinematic equation of MR jet.Thirdly,experiments were conducted to observe the jet structure of the MR jet under the external magnetic filed.Finally,the stabilization of axial magnetic field on MR jet was analyzed based on the knowledge of continuous medium.And the results are consistent with the experimental ones.The longitudinal chain-like fibrillation and subsequently high apparent viscosity within the MR jet induced by a local axial magnetic field can suppress jet breakup in the stage of initial dynamic disturbances and result in a stable and collimated jet remaining for a relatively long distance.Due to the insensitivity to the offset distance MJP has potential advantages in deterministic precision polishing of complex shapes of steep concave optics and cavities.