Animals adapted through evolution to sustained and fast swimming and flying have had to solve an engineering problem: how to move a certain mass and/or volume with minimum fluid-dynamic drag and minimum cost of transport. Over millions of years the evolutionary process has created and tested a wealth of ideas and designs. Shape optimisation in conjunction with the use of natural and artificial cavitation, polymeric additives injection, compliant coatings and riblets, have been identified as important mechanisms in fluid-dynamic drag reduction. Theoretical and experimental investigations of drag and flow-noise reduction methods have had some success, but the physical processes are not yet well understood and used.

In a systematic study combining the efforts of biologists, physicists and engineers, the fluid-dynamic properties of a series of low-drag bodies known from nature will be investigated in order to improve theoretical models of near-wall flows, and of their control in different flow conditions, and to find new ways of minimising drag, flow-noise and energy losses in engineering. Based on large data sets recently available from morphological and fluid-dynamic studies on flighted birds, penguins and dolphins, which are adapted to different ranges of Reynolds numbers, the aim is to concentrate on scale effects in shape optimisation.

Experimental investigations conducted on models and carcasses in a wind tunnel and/or water tank, and particularly also on live animals (e.g. penguins will be studied in a 21m long swim canal in Antarctica), should provide additional data on total body drag, velocity and pressure distribution along the body surface and boundary-layer configurations such as transition from laminar to turbulent flow at different flow conditions.

The aim is to gain an understanding of the interaction between body shape and surface structures in the process of drag and flow-noise reduction, to improve current theoretical models of near-wall flows and of their control and, finally, to translate the results and proportions found in nature into designs and dimensions applicable in engineering. Computer simulations in conjunction with the Evolution Strategy work programme will therefore be conducted.