抄録
A laser induced fluorescence (or luminescence) method was used to investigate the flow field of a steady laminar developing flow in a U-bend of square cross-section. Visualization of velocity profile across the duct was attained by observation of a luminous curve consisting of a swarm of fluorescing tiny particles irradiated by a nitrogen pulse laser. Both of axial velocity profiles in the directions of centrifugal force and perpendicular to it were visualized and measured at five cross-sections of different bending angle θ. As a result, the flow velocity field was clearly measured, and those results of the LIF measurement were compared with that of LDV measurement. Both approximately agreed each other.
