Flow measurement around organisms and surrogates
This chapter reviews methods of measuring turbulent fluid flowing through and around flora and fauna. It begins with a discussion of the relevant aspects of the nature of turbulent flows and highlights difficulties associated with their measurement. Detailed discussions of turbulent flows can be found in many textbooks, including Tennekes & Lumley (1972), Hinze (1975), Nezu & Nakagawa (1993), Pope (2000) and Davidson (2004) and are not repeated here. Here, the focus is on generic issues that affect the successful measurement of turbulent flows, irrespective of the technique adopted and the crucial issue of selecting an appropriate measurement duration. There is a summary of relevant techniques with a detailed review of how each one has been used with biota or surrogates, including past deployments, and an overview of relevant strengths and weaknesses. Finally some suggestions about standardised reporting of instrument deployment and data processing are presented, which if adopted, would provide adequate grounds for critical evaluation of reported data and promote best practice.