Vertical Velocity Distribution Characteristics Research In Smooth Open Channel

Based on the classification of types of uniform and non-uniform flow for open channel flows, the vertical velocity distribution characteristics were extentive studied of smooth open channel under researchers' studies. Compared with different hydraulic characteristics between uniform and non-uniform flow, also be discussed and interpreted. Conclusions were summed up in the following:For steep and gentle slope, uniform flow have similar regions ,the logarithmic law approximates adequately the date throughout the entire channel depth., a wake does exist. being of limited The log-wake law for describing the velocity profile is not better than the logarithmic law. Re effect isn't obvious to Karman value .For steep slope,Karman value is smaller than for gentle slope.S₁ S₂ M₁ M₂ non-uniform flow both have similar regions, Karman value in M₂ non-uniform flow is bigger than in M₁ non-uniform flow. The log law equation precedor obtained could describe the velocity profile well for straight slope pen channel. Boundary layer thickness in supercritical flow is smaller than subcritical flow. Uniform and non-uniform flow both have similar tubulence intensity distribution.Counter-slope flow has regions, vertical velocity distribution is described well by log law in turbulence region. The log law equation precedor obtained could not describe the velocity profile well for counter-slope.It indicates that one needs carefully to apply velocity profile into practice because this study shows the complex characters of open channel. Turbulence intensity for counter-slope flow is smaller than for gentle slope.