Furrow geometric parameters

Trout, Thomas J. (1991) Furrow geometric parameters. Journal of Irrigation and Drainage Engineering. 117(5):613-634.

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Abstract

Furrow shape information is required for modeling and evaluating
furrow irrigation. Currently used shape models assume the furrow perimeter is rigid
so that only the flow depth increases with capacity. Actual furrow perimeters are
not rigid and may widen as their capacity increases. If the furrow width increases
proportionally with flow depth, the flow cross-sectional shape remains constant
and only the size increases with capacity. This constant-shape model results in
simple generalized relationships between the hydraulic and geometric parameters,
which simplifies analysis of the complicated interactions that occur during furrow
irrigation. The two shape models are compared conceptually and against field
measurements. The rigid-perimeter model better matches field-measured furrow
shapes and is easier to rationalize conceptually. However, both models match the
important relationships between furrow geometric parameters and hydraulic parameters
equally well. The most important relationship between flow area and
uniform flow section factor is insensitive to both the model and shape. The predictions
of both models are more sensitive to the furrow top width-to-flow depth
ratio than to shape.

Item Type:	Article
NWISRL Publication Number:	0752
Subjects:	Research methodology Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:53
Last Modified:	06 Dec 2016 23:51
Item ID:	562
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/562