over a wavy wall 257 Abstract Measurements of the spatial and time variation of two components of the velocity have been made over a sinusoidal solid wavy boundary with a height to length ratio of 2a/2 = 0.10 and with a dimensionless wave number of ~ + = (27t/2) (v/u*)= 0.02. For these conditions, both intermittent and time-mean flow reversals are observed near the troughs of the waves. Statistical quantities that are determined are the mean streamwise and normal velocities, the root-meansquare of the fluctuations of the streamwise and normal velocities, and the Reynolds shear stresses. Turbulence production is calculated from these measurements.The flow is characterized by an outer flow and by an inner flow extending to a distance of about c~-1 from the mean level of the surface. Turbulence production in the inner region is fundamentally different from flow over a flat surface in that it is mainly associated with a shear layer that separates from the back of the wave. Flow close to the surface is best described by an interaction between the shear layer and the wall, which produces a retarded zone and a boundary-layer with large wall shear stresses.Measurements of the outer flow compare favorably with measurements over a flat wall if velocities are made dimensionless by a friction velocity defined with a shear stress obtained by extrapolating measurements of the Reynolds stress to the mean levels of the surface (rather than from the drag on the wall).

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The focus of flow assurance analysis and design has often been from flowline entry to the initial separator at the production facility. This paper focuses on the flow assurance issues that pertain to the well, with emphasis on the subsea well located in cold environments. Consideration is given to design and operational issues that result from management of flow assurance related to hydrates, with a brief discussion of other issues, such as wax, asphaltenes, and chemical compatibility issues.

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