On the basis of Stewartson-Wedemeyer theory and Murphy method, a constant Cf representing the ratio of centrifugal force to liquid surface tension is introduced for studying the influence of liquid sloshing within the body to resonant instability frequency band. 引入表示离心力与液体表面张力之比的常数Cf,以Stewartson&Wedemeyer理论和Murphy方法为基础,研究腔内液体晃动对共振不稳定频带的影响。