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In this study, apparent ferro-viscosity on applied directional field, through the evaluation of mean piping flow velocity, is examined. Here viscosity in magnetized ferro-flow is found to be closely dependent on the field intensity as well as direction, which is quite different from the constant thermal property usually used in traditional fluid dynamics problem. To predict ferro-magnetization and ferro-viscosity induced under horizontal and vertical field imposed , an auxiliary electromagnetic mechanism is then designed and set up ,As a result, the apparent viscosity ,for ferro-concentration ψ0.4 and 0.04 exposed to field in different direction, will initiate a faster growth within field strength of 6~12 mT where the quick magnetization of ferro-particles starts working, and magnetic field along with flow direction is found to have more potential to induce viscous drag. While compared with theoretic results on Brownian relaxation theory in Langevin function, experimental vortex viscosity behave a good agreement within the working magnetic intensity 0~36 mT and their maximum relative errors will be less than 10% and 50% for ferro-concentration ψ0.4 and 0.04 at working temperature at 25 o c.

In this study, a 2-D model with dimensionless analysis was proposed by discussing the roles of the active material properties in high energy beam drilling. With the assumption of small Pelect number, quasi-steady transformation and scalar analysis in this model, several dimensionless parameters had been generalized. Among these parameters, the dimensionless material property , defined as evaporation latent heat to internal energy at melting point, was proven to be the key member; which not only significantly influenced the nonlinear variation inside the work piece, but also directly determined the penetration results whose behavior showed a resemblance to the distribution of exponential function in . Further more, the maximum efficiency had been successfully estimated, and the dramatic change of drilling characteristic during the transitional energy region was also reasonably simulated. When compared with the experimental results from Allmen [1], the present model with given copper properties showed an excellent agreement on material removal rate (their relative errors were not more than 15 ％.)