Hydraulic modelling of a sharp crested labyrinth weir
General Material Designation
[Thesis]
First Statement of Responsibility
A. T. Sitompul
Subsequent Statement of Responsibility
J. J. Sharp
.PUBLICATION, DISTRIBUTION, ETC
Name of Publisher, Distributor, etc.
Memorial University of Newfoundland (Canada)
Date of Publication, Distribution, etc.
1993
PHYSICAL DESCRIPTION
Specific Material Designation and Extent of Item
239
DISSERTATION (THESIS) NOTE
Dissertation or thesis details and type of degree
M.Eng.
Body granting the degree
Memorial University of Newfoundland (Canada)
Text preceding or following the note
1993
SUMMARY OR ABSTRACT
Text of Note
A labyrinth weir is an attractive alternative for water level control in flat land where the head is usually limited. The advantages occur because the crest length of a labyrinth weir is significantly longer than the width of the river. This is achieved by having a plan form which consists of repeating geometric cycles, typically trapezoidal in form. As a result large flow can be released at relatively low heads. Trapezoidal and triangular forms have become the favoured geometric cycles for designers. Experimental and theoretical results confirmed that the trapezoidal shape with the side wall angle, usd\alphausd = 0.68usd\alpha\sb{\rm max.}usd and the length magnification, 1/w = 2.65 gave the best hydraulic performance among other labyrinth weir plan forms which were tested in this study. Such a crest is useful when a river has a large quantity of debris. The economic advantages of labyrinth weirs were also studied with reference to the Ciwadas trapezoidal labyrinth weir which was constructed in Indonesia in 1988. This labyrinth weir was designed to handle the flood flows of 200 m/s and control water depths between 1.6 m and 2.35 m. Comparison with a typical weir with gate shows that this labyrinth weir was more than 25% less expensive. A computer code for analytical studies was also established. It was shown that for trapezoidal plan forms, a good agreement between theoretical results and experimental data could be achieved. (Abstract shortened by UMI.)