对Roscoe粘度公式中λ_0取值的研究

ON THE ADOPTION OF λ_0 VALUE FOR ROSCOE'S EQUATION

通过对Roscoe绝对粘度计算公式的适用条件和推导过程的研究,提出了由实验测量液态金属的深度H与振动对数衰减率λ的关系曲线,并将其外延到H→0时所对应的λ值,作为原λ_0的取值(记为λ_f)的方法,液态Cu和Sn的实验结果表明,所提出的方法不仅满足原公式的使用条件,而且消除了“端面和滑动”等影响,使计算准确。

Considering the availability and derivation of Roscoe's equation for absolute viscosity calculation, the method to adopt λ_0 value, so-called λ_f, was proposed by experimen- tally determining relational curve of the measured height,H,of metal melt vs logarithmic oscillation decrement,λ, extrapolating H into zero, if such corresponding λ value is taken. Ex- perimental results show that the proposed method not only satisfies the availability of original equation but also eliminate the effects of:'end and slippage', so as to improve the accuracy for liquid Cu and Sn examinations.