The transverse vibration characteristic of the viscoelastic sandwich beam with axial speed is studied under the coupled temperature field and displacement field. Based on the theory of Euler - Bernouli beam and the constitutive relation of Kelvin viscoelastic material model, the transverse vibration equation of the axially moving beam is established ; considering the interaction of the material deformation and the heat conduction, the coupled governing equation of the beam is obtained. and the coupled thermoelastic dynamics system are obtained by Galerkin method. The related thermal parameters on the vibration frequency are analyzed by using numerical method.

Electron behaviors in the whole cathode space of a steady argon MHCD with a variable cathode gap have been simulated on the model of Monte Carlo collisions. As the cathode gap alters, the hollow-cathode effect in MHCDs has been studied by the variety rule of electron spacial and energy distribution. The results reveal that a too wide gap between two opposed cathodes under a settled pressure will die down the hollow-cathode effect.