“…No single, simple GA mechanism appears to work well all the time. For example, grid adaptation is relatively straightforward in more elementary applications such as in flows past ''irregular" boundaries [63,15,62,16,35,2,54]; free surface flows [34,22,65,33]; or in tracer transport [7,14,2,21]. In these examples focusing the GA on boundary shape or targeting various combinations of tracer magnitude, gradient and/or second derivatives of the tracer field have all produced good results.…”