1905年 white 将球磨简化为旋转筒壳中具有一个球的情形,并假定球在“抛离”壳体前二者间无相对运动,从而导出了临界转速公式。以后,Левенсен等人将临界状态改为壳球间无相对滑动,又得到一个临界转速公式,进而按二者间无相对滚动再得第三个临界转速公式。当然,后两个公式均涉及摩擦系数。 In 1905, White reduced ball milling to the case of a ball in a rotating cylinder shell and assumed that there was no relative movement of the ball between the “throw-away” case and the critical velocity formula. Later, Левенсен et al changed the critical state to no relative slip between the shells and obtained a critical rotation speed formula, which was further compared with the third critical rotation speed formula with no relative rolling between the two. Of course, the latter two formulas all involve the coefficient of friction.