whats the hydraulic radius? and does it increase as you move downstream and why thanks x?

Answer 1

The hydraulic radius is defined as the ratio of the cross-sectional area of a flow channnel to the wetted perimeter of the flow: A/P. The hydraulic radius thus has units of length.

In dealing with the hydrology of fluvial systems, the hydraulic radius appears most commonly in the various empirical formulas for determining flow velocity (e.g., the Manning equation).

If you are asking about natural fluvial systems (as opposed to other types of fluid transport systems, e.g., blood vessels), I don't think you can make a general statement about whether the hydraulic radius increases or decreases as one moves downstream -- it depends on the nature of the stream system. For instance, the hydraulic radius of a braided stream system in the flood plain at the terminus of a river would have a small hydraulic radius (shallow, wide channels have low area/perimeter ratios), but I would imagine that at for at least part of a river system's length, the hydraulic radius of the main channel would increase as a function of distance downstream, so long as the cross-sectional geometry remains roughly the same, but simply increases in area (i.e., for a given 2-D shape, the area increases faster than the perimeter as that shape gets larger).

Answer 2

Hydraulic Radius Of A River

Answer 3

Ratio of the cross-sectional area of the flow at a point in an open channel or closed conduit to the wetted perimeter, that is, R = A/P.
Yeah!!

Answer 4

Perhaps you mean hydraulic gradient? Increases as you move down stream

Throw that info into your equation and you'll figure it out.

Answer 5

hi