1. A method of identifying a configuration of an object that satisfies a predetermined optimisation criterion under specified conditions, the method comprising the steps of: (i) specifying a plurality of different object configurations; (ii) for each specified object configuration, using a first simulation procedure to simulate the specified conditions so as to generate data that can be used to evaluate the object configuration against the optimisation criterion, wherein the first simulation procedure comprises iteratively calculating values of variables characterising the object configuration; (iii) identifying a functional relationship between the data generated for each specified object configuration; (iv) using the functional relationship and the optimisation criterion to select a data point, and identifying an object configuration corresponding thereto; and (v) using a second simulation procedure, simulating the specified conditions in respect of the identified object configuration, wherein the second simulation procedure comprises iteratively calculating values of variables characterising the object configuration until the values satisfy a convergence criterion, wherein, for at least one of the specified object configurations, the first simulation procedure is completed before the values calculated therein satisfy the convergence criterion used in the second simulation procedure.