Micro- and Macro-scopic Study of Two-phase Flow on a Stepped Chute
نویسنده
چکیده
Stepped chute flows are characterised by intense turbulence and strong flow aeration (Fig. 1), but most studies did not investigate the turbulence characteristics. Detailed air-water flow properties were measured in skimming flow on a stepped chute (θ = 16o, h = 0.05 m). Longitudinal oscillations of depth-averaged flow properties were observed with a wave length of about two step cavity lengths. High turbulence levels were recorded downstream of inception, and the data were correlated to the air-water interface area. In the bubbly flow region (C < 0.3), bubble size distributions demonstrated a broad range of entrained bubbles, with a fair proportion associated with a bubble cluster structure. Overall the results emphasise the complexity of air-water skimming flows down stepped chutes.
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