本文之主旨在於利用轉移矩陣法來求解由一系列的軸與圓盤所構成的轉子系統，在油膜軸承支撐下的旋動頻率(whirling frequency)。
文中以二維的樑來介紹轉移矩陣法之基本原理，然後再用三維的樑理論來推導軸、圓盤及油膜軸承的轉移矩陣。最後再用轉移矩陣法來求得系統的特徵方程式，則與特徵方程式之極小值對應之特徵值即為轉子軸承系統的旋動頻率。本文對於旋動頻率與一般旋轉軸之臨界轉速的關係亦有扼要的探討。

The purpose of this paper is determining the whirling frequency of rotor systems, mounted on oil-film bearings. The rotor is described by a series of shafts and disks. Transfer matrix methods are used to determine the characteristic determinant of system.
In this paper we use the beam of two dimensions to introduce the basic theorem of the transfer matrix method. Then, we use the theory of the beam of three dimensions to derive the transfer matrices of shafts, disks and oil-filmed bearings. Finally, we use the transfer matrix method to determine the characteristic equations, and the minimum corresponding eigenvalues are the whirling frequencies of the rotor-bearing system. In this paper we have the summary discussing with the whirling frequency and critical speed.

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