Turbulent velocity field in isothermal and heated liquid flow through a vertical annular channel

Abstract

Time-mean axial and radial velocities, axial and radial turbulent intensities and the single-point cross-correlation between axial and radial turbulent velocity fluctuations (∼axial Reynolds shear stress) were measured in unheated and heated turbulent upflow of liquid Refrigerant-113 through a vertical concentric annular channel. Time-mean temperature and temperature fluctuation intensity were measured in the heated flows. A two-component laser Doppler velocimeter was used for the velocity measurements and microthermocouples for temperature measurement. Results are reported for Reynolds numbers of 18 000, 28 450 and 40 480 at inner wall heat fluxes of 0, 9000 and 16 000 W m −2. Buoyancy effects were found on the time-mean velocity and turbulence fields, even at very low values of Gr Re 2 . Mechanisms suggested by Petukhov and Polyakov explain these effects. The results should be useful in the development and validation of turbulence models for such flows.