A numerical solution of the nonlinear macroscopic laser‐fluid equations for propagation of a Gaussian laser pulse in air is described. The concept of ``utility analysis'' of numerical differencing schemes is introduced. With the computation scheme used, the laser pulse could be followed for only 10−5 sec; so enormous energy was put into the pulse to enhance the interaction with the fluid. Thus the initial pulse distortion could be observed. Analytical evaluation of the computer results produces a detailed quantitative check and suggests that a combination of analytic and numerical methods would allow a pulse to be conveniently followed for much longer periods of time. The preceding paper by the same authors describes various types of instabilities to be anticipated for propagation over long periods of time or with large powers.
