Submitted to: Journal of Irrigation and Drainage Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/1/1998
Publication Date: N/A
Technical Abstract: This paper is a discussion of an article published on idealized control of sloping canals. The discussion agrees with a number of insights provided by the paper but disagrees with several ideas put forth. First, it is pointed out that the paper deals only with feedforward control and implies that effective feedback control can be derived from it. Second, canal pool lproperties needed for designing feedback controllers are different from those needed for feedforward controllers. It is felt that the author's suggestion of using the average Froude numbers as an important property is not very useful in practice. Alternate properties are suggested. A different equation is provided for predicting wave travel times, based on the speed of a kinematic shock wave. The need for decoupling simple canal pool controllers is discussed along with ways to provide this decoupling. It is suggested that a variety of control methods are needed for different situations.