The theory study on unstable spiral wave in the circular vortex
流体涡旋中螺旋波不稳定发展的理论研究

Through seeking the first analytical solutions of equation,this article studied unstable spiral waves in vortex(in Column coordinate),the result is,spiral waves will develop through the resonance action between the waves and base flow.The growth rate has close relation to wave number.Numerical calculation indicates that in the process of development,the spiral structure of wave becomes more and more obvious,spiral angle will become smaller and smaller.