Abstract-The task of the combustion engineer is reviewed in the light of available numerical methods,and it is demonstrated how these numerical methods have influenced this task. Examples are shown of application to combustor pattern factor improvement, to diffuser flow and loss optimisation, and to cooling device design improvement. The power of a coupled mesh technique and the flexibility of a boundary fitted orthogonal mesh system are demonstrated to be essential features in the success obtained in applying a single code to all these combustor problems.