抄録
A method is proposed to analyze dynamic response of a string with time-varying length. In this paper, we derived a finite element model of the string on the assumption that the tension of the string is constant and the length varies at constant speed. The finite element model consist of many constant elements and a telescopic element. The constant element is an ordinary finite element string model and the telescopic element is a finite element of which length varys with time. The equations of motion with time-varying coefficients are derived and solved by direct method such as the Wilson q method to calculate the dynamic response of a string. Numerical results are compared with exact solutions and the validity of this method is verified.
