Adding the alongshore current

This case is still confusing. Here is a comparison between the results for Case 2 (slightly different frequencies and equal/opposite angles) and Case 3 (slightly different frequencies, two different angles that give a 3.5 degree carrier wave angle).



Case 2 still has a mean alongshore current which we've attributed to nonlinearity (I haven't actually looked at the balance to verify). Case 3 which is expected to have a mean negative longshore current has practically none. Could it just be that the alongshore current we expect to see (~ 15cm/s) is just compensating for the nonlinearity we saw in Case 2 (~14 cm/s) ??