将螺旋槽型动压气体止推轴承(spiral groove gas bearing,SGGB)与主动磁轴承相结合,搭建了轴向磁气组合轴承转子系统试验台。通过仿真分析,研究了槽深、槽数、槽宽比、槽端半径比和螺旋角等结构参数对螺旋槽型动压气体止推轴承承载力的影响。通过高速旋转试验,研究了螺旋槽型动压气体止推轴承的实际承载力和系统的动态性能。通过跌落试验,验证了螺旋槽型动压气体止推轴承作为轴向保护轴承的可行性。研究结果表明,引入螺旋槽型动压气体止推轴承,有助于提高系统的动态性能,当轴向磁轴承失效时,可减轻转子直接撞击造成的损害。
An equation of state(EOS) is a thermodynamic equation describing the state of matter under a given set of physical conditions,and the Mie-Grüneisen EOS is a widely used EOS for solid materials.Polyimide is a typical complex high-molecular polymer of imide monomers which is widely used in the manufacture of parts for aerospace technology and for fabricating the inertial fusion energy shells(IFE).When a spacecraft collides with a meteoroids(or orbital debris) or the IFE shells are radiated by high power laser,the polyimide used in the equipment is in high pressure state.In order to study the safety of the spacecraft and IFE shells,the EOS of polyimide should be determined.In our research,the three key parameters of the Mie-Grüneisen EOS based on the shock adiabat for polyimide have been determined with two-stage light-gas gun experiments,i.e.the bulk speed of sound of polyimide is determined as 2.62±0.22 km/s,the linear Hugoniot slope coefficient is determined as 1.25±0.063,and the Grüneisen parameter at initial state is determined as 1.53±0.135.The Mie-Grüneisen EOS for polyimide is finally obtained,and the parameter values are proved reliable via the comparison of Grüneisen parameter value calculated from two different theoretical models using the experimental data.
脉冲电子束辐照材料试验研究中,束流电子具有不同的速度和角度分布。但数值模拟计算一般都考虑电子束垂直入射靶材料,这可能导致数值计算结果与试验结果不符。针对该问题,提出了一种计算电子束辐照下能量沉积剖面的新方案,利用MCNP(Monte Carlo N Particle Transport Code)软件对铝、铜、钽金属材料在电子束辐照下的能量沉积进行模拟,分析了电子束垂直入射与带有角度分布入射时能量沉积的差异,为解释电子束辐照试验测量数据与理论计算结果之间的差异提供了依据。
