University of Tasmania, Australia

Impact of biological surfaces on near wall flow and boundary layer development

All systems involving the relative movement between a fluid passing a solid boundary result in a loss of energy due to skin friction at the solid/fluid interface. A reduction in carrying capacity of canals and pipelines occurs due to the deterioration of the internal lining. This problem is exacerbated by the presence of biofilms. A 10% reduction in flow carrying capacity has been measured in a hydroelectric canal in Tasmania due to the seasonal growth of the diatom species Gomphonema tarraleahae.

The detrimental effect of biofilms on drag is well established and the increases in frictional resistance and resultant energy losses are of concern to industry including ship owners, bulk water suppliers, and hydroelectric power generators.

The proposed project will investigate the development of the boundary layer in the presence of biofilms, using a purpose built water tunnel and commercial Laser Doppler Velocimetry system. Artificial biofilms will also be used to simulate specific aspects of the known biological biofilm to investigate the mechanisms for energy transfer and turbulence generation due to different features of the complex biological structure. New surfaces will then be developed in order to utilise the known energy transfer mechanisms in an attempt to develop surfaces with characteristics that may be useful for industrial application.

The biological aspects of the project will be supported by collaboration with Plant Scientists. In addition to generic research skills, the successful candidate will develop skills in the measurement and analysis of boundary layer flows using modern laser measurement techniques.