Density distribution in the vortex shedding problem at time t = 3.8    ×    10² in the innermost region of the grid, close to the cylinder, computed by restarting and performing 80 time steps with the implicit scheme as described in the text. The outer part of the grid, which extends to 20 cylinder diameters, is not shown. Fifty equidistant contours are used between the density minimum and maximum.