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It Is shown in this paper that, once the problem of designing dynamically optimal mechanisms is formulated as a constrained minimisation problem, genetic algorithms provide a procedure for solving this design problem which is very powerful but also very simple. These general results are illustrated by the genetic optimisation of a particular four-bar linkage that was previously optimised non-genetlcally. However, It is pointed out that the genetic design methodology described in this paper can in principle be used to minimise any desired combination of forces and couples in any mechanism.

Numerical simulations have been conducted to simulate the flow over an oscillating NACA 0012 airfoil operating at various Mach numbers, oscillatory frequencies and mean angles of attack, for nominally attached flow conditions. The simulations have been carried out using the ANSYS-CFX5 flow solver, to assess the performance of this tool in conducting unsteady aerodynamic analysis of this nature. Numerical results are compared to the experimental work of Landon, and discussed in relation to previous numerical studies. Overall a good agreement is found for the majority of cases, however, a number of discrepancies have been noted and discussed, particularly regarding simulation of high mean incidence angles and subsonic Mach numbers.

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