抄録
An experimental study using a hot-wire anemometer was conducted to investigate fully-developed turbulent flows within ducts of a cross-chaped cross-section. Extensive measurements of mean velocity and Reynolds stress fields were made at 972 measuring points distributed over an entire cross-section. Examination of the experimental data including the secondary flow velocities and separation of normal stresses, confirmed that the flow field acquired a high degree of symmetry in all planes of symmetry. The resulting contour maps of various quantities were compared against the numerical calculation results based on Launder and Ying's algebraic stress model. The overall performance of the algebraic stress model was found to be satisfactory. The model, however, tends to underestimate the size of secondary vortices generated near the convex corner. Moreover, discussions were made on the secondary flow vorticity production in connection with isovels. The present study may give certain information which may be useaul for a further improvement of the stress model.
