51 | 51 | Note that we must initialize the left and right state of the Riemann problem (where the discontinuity corresponds to the interface between the grid and the boundary zones) such that the generated wave fan yields a shock traveling to the right into the grid at 2,000 km/s. In other words, we solve the R-H jump conditions across a 2,000 km/s shock using the pre-shock values of the gas in the grid, and initialize the boundary zones with those values. If the incoming flow does not match the jump condition values, additional wave fans will be generated once that flow collides with gas in the box. To illustrate this, see the following image which shows an initial inflow at the boundary that has slightly different values than those specified by the jump conditions, compared to the true values (right). |