DELTA-PERTURBATION EXPANSION FOR THE NORMAL FLOW DEPTH PROBLEM IN RECTANGULAR CHANNELS

L. AMARA, B. ACHOUR

Abstract


The normal flow depth is an important parameter in the design and analysis of free-surface flow problems for both man-made and natural channels. The implicit character of the governing Manning’s equation in rectangular-shaped channels requires a trial and error process for the computation of the normal flow depth, which sometimes leads to a large sequence computation. In this paper, a novel exact analytical approach based on the -perturbation expansion is proposed as a solution to the issue of computing normal depth in channels with rectangular cross sections. For practical purposes, the explicit analytical expression obtained provides a particularly precise solution. To show the application of the suggested approach, some examples are presented as illustrative examples.


Keywords


Normal flow depth, Rectangular channel, Analytical solution, Delta-perturbation method.

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References


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