Fig. 3. Cross-sectional profiles of the relative velocities in each zone of the flume, by nominal velocity. Data are for flow rates of 1.5 m s^-1 (A), 2.5 m s^-1 (B) and 3.5 and 4.5 m s^-1 (C), and were used to calculate the correction factors in Table 1 (see text for details). Arrowheads, location of the water surface.