Current Investigations of Turbulent Shear

The paper covers first a short review of the history of research on turbulent shear and second a description of current experiments which may lead to further understanding. The first portion categorizes the kinds of data which have been taken and discusses what can be learned from each. It then summarizes what is firmly established concerning the nature of turbulent shear, mostly from work of the past decade. A description of the several interpretations of these data under theoretic study by current leading researchers is then given. The second portion of the paper discusses the extraordinarily difficult problem of identifying and measuring the actual production of turbulence in a boundary layer. The difficulties arise from the fact that production is a partly-coherent, intermittent process buried in relatively high amplitude noise. The measurement problems are discussed and a potential solution for the measurement of turbulence production with adequate accuracy is proposed