Measurements of the Turbulence Structure Downstream of a Tube Bundle at High Reynolds Numbers

Abstract

Mean and turbulent velocity profiles are measured in natural gas at a static pressure of approximately 5200 kPa and a Reynolds number of around 7 × 106 . These measurements are obtained by conventional hot film anemometry suitably modified for use in a natural gas environment. Measurements are taken in a 102.26 mm nominal diameter pipe following a development length of around 76D. The mean velocity profile and the turbulence intensities at this location are typical for a fully developed pipe flow. Further, measurements downstream of a 19 tube bundle flow conditioner are also presented. The tube bundle is traversed downstream of a 90 degree, long radius (r = 1.5D) elbow and the measurements are taken at 19D downstream of the elbow exit. Measurements include those of the axial mean and turbulent velocities and the integral length scales. It is found that the decay of turbulence is slower and the magnitude of the length scale is smaller in comparison to measurements at lower Reynolds numbers. Orifice meter comparisons, performed in a 19D test section (meter run), confirm earlier findings that turbulence is one of the factors that affects orifice meter accuracy.