Modification for the Chisnell's method of approximate analytic solution of the converging shock wave problem

The self-similar problem about a convergence to the centre of a strong shock wave is discussed. The approximate analytical solution which has the same form as the Chisnell's solution is proposed. The simple expressions for definition of self-similar representers of the velocity, density and square of the sound speed are written down. The self similar exponent is determined by solving the algebraic equation. The achived results correlate better with the exact solution of the classical numerical method.