AppendkA. Prototype Labyrinth Spillways

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1 AppendkA Prototype Labyrinth Spillways 131

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3 HYDRAULIC DESIGN OF LABYRINTH WEIRS 133 Labyrinth Spillway Installations noted in the Literature Nae Country Year Built Q 3/s Ho P W L n Source Agua Branca Alfaiates Alijo Arcoss6 Avon Bartletts Ferry Belia Beni Bahdel Boardan Calde Carty Ciia Dungo Estancia Poutugal Australia Zaire Algeria Italy Angola Venezuela * /.0.76*.5.8/ Quintel et al (000) Quintel et al (000) Magalhaes (1989) Quintel et al (000) Darvis(1971) Mayer (1980) MagalhSes (1989) Afshar(1988) Babb(1976) Quintel et al (000) Afshar(1988) Lux/Hinchliff (1985) Lux (1989) Magalhaes (1989) * Sloped upstrea apron. The iniu diension at the upstrea apex is given. ** Another type of spillway was constructed.

4 134 HYDRAULIC DESIGN OF LABYRINTH WEIRS Nae Country Year Built Q 3/s Ho P W L n Source Forestport Lux (1989) Garland Canal Gea Harrezza Hyru Influente Jutarnaiba Keddera Kizilcapinar Mercer Navet OhauC Canal Pacoti Pisao Quincy Ritschard Algeria Mozabique Brazil Algeria Turkey Trinidad New Zealand Brazil ** * 3.5* * Lux/Hincliff (1985) Quintel et al (000) Lux (1989) Lux (1989) MagaMes (1989) Afshar(1988) Lux (1989) Yildiz(1996) CHM Hill (1976) Phelps (1974) Walsh (1980) MagaMes (1989) Quintel et al (000) MagalhSes (1989) Vereyen (1991) * Sloped upstrea apron. The iniu diension at the upstrea apex is given. ** Another type of spillway was constructed.

5 HYDRAULIC DESIGN OF LABYRINTH WEIRS 135 Nae Country Year Built Q 3/s Ho P W L n Source Rollins ** Tullis(1995) Saco S. Doingos Sa Rayburn Lake Santa Justa Sarioglan Sarno Teja Ute Woronora Nae Flaingo Tongue River Twin Lake Brazil Turkey Algeria Australia *** * Quinetal(1988) MagalhSes (1989) USCOLD Bulletin (1994) Lux (1989) Yildiz(1996) Afshar(1988) Quintel et al (000) Lux (1989) Afshar(1988) * Sloped upstrea apron. The iniu diension at the upstrea apex is given. ** Another type of spillway was constructed. *** Distribution of heads and discharges restricted by Departent of the Ary after Septeber 11,001. Labyrinth Spillway Installations not noted in the Literature Country Year Built Q 3/s Ho.3.74 P W L n 4 4 Location Las Vegas, NV Decker, MT Buffalo, WY The plan and profiles of a few of these installations are shown on the following pages to illustrate the varied configurations that have been used.

6 136 HYDRAULIC DESIGN OF LABYRINTH WEIRS AVON Avon Spillway - Australia Avon spillway is unusual in that the labyrinth axis is curved in profile. In addition it is uch wider than the downstrea channel. Inlet conditions with this spillway are not significant because of the large nuber of cycles. Convergence and supercritical wavers in the channel need to be considered.

7 HYDRAULIC DESIGN OF LABYRINTH WEIRS 137 BARTTLETTS FERRY The labyrinth spillway is 100 ft wide and consists of 40 cycles of triangular weirs. Due to the very wide spillway and the large nuber of cycles, supercritical waves in the downstrea channel are not significant. Lateral flow at each ebankent ay decrease the predicted axiu discharge for this structure. An overall odel of the installation or a nuerical odel of the reservoir should have been perfored to deterine if the inflow velocity vectors affect the discharge. Apparently only sectional odels of one and two cycles were studied. As a result, the predicted discharge for the structure ay be higher than that realized in nature.

8 138 HYDRAULIC DESIGN OF LABYRINTH WEIRS BOARDMAN The entrance conditions to this spillway are very iportant because of the sall nuber of cycles. Due to the sall radius of curvature at the inlet, separation will occur on the walls leading to a saller than expected axiu discharge. Supercritical waves in the channel are iportant. These were investigated in the odel studies.

9 HYDRAULIC DESIGN OF LABYRINTH WEIRS 139 GARLAND CANAL The structure is used to provide a constant head for a downstrea turbine. The canal conveys large suspended sedient loads that deposit between the upstrea sidewalls. During high flows the sedient is flushed out of the labyrinth. The sluice gate on the centerline of the canal was provided to pass the sedient downstrea. Because of the sluicing action of the labyrinth, the sluice gate is not used. This structure required extensive nuerical studies to develop the transition shape downstrea of the labyrinth.

10 140 HYDRAULIC DESIGN OF LABYRINTH WEIRS HYRUM The inlet section to this spillway was developed by odel studies that included changes to the location along the axis of the chute, varying the abutent conditions, and inverting the weir. Supercritical waves existed the entire length of the chute. To eliinate the a longer transition would have been necessary. As an alternative, higher chute walls were selected to be the ost cost effective solution.

11 HYDRAULIC DESIGN OF LABYRINTH WEIRS 141 KIZILCAPINAR This structure is unusual in that the axis of the labyrinth is curved. To reduce the tendency for subergence on the downstrea side of the structure, the downstrea invert was depressed. Extensive odel studies were necessary to deterine the best proportions for the weir height and the downstrea invert elevation.

12 14 HYDRAULIC DESIGN OF LABYRINTH WEIRS RITSCHARD This structure was studied with a physical odel. However, it was never built because the PMF was reduced after the odel investigation. This structure is located at,300 elevation. The original PMF was calculated fro the PMP at sea level. However, since the aount of water that is contained in the atosphere is less at,300 eters, the PMP could be reduced, which resulted in a lower PMF. The approach flow conditions to the labyrinth are good. With a large nuber of cycles, supercritical waves in the downstrea channel should interact with each other to produce an alost unifor flow depth where the discharge flows into Muddy Creek.

13 HYDRAULIC DESIGN OF LABYRINTH WEIRS 143 SARIOGLAN This structure uses an expanded upstrea section to increase the length of the spillway. The expanded section is joined to the downstrea channel with a curved transition. A drop on the downstrea side of the weir was provided to eliinate the tendency for subergence. The entire geoetry shown in the plan view was siulated in a odel to insure that the structure would perfor as designed.

14 144 HYDRAULIC DESIGN OF LABYRINTH WEIRS UTE This installation placed a labyrinth weir iediately upstrea of an existing ogee crest. The ogee crest was not reoved. Flow disturbances were noted on each end of the spillway. Abutent odifications did not affect the discharge capacity. Supercritical waves in the downstrea channel were not significant.

The Hydraulic Design of an Arced Labyrinth Weir at Isabella Dam

Utah State University DigitalCommons@USU International Symposium on Hydraulic Structures Jun 28th, 1:30 PM The Hydraulic Design of an Arced Labyrinth Weir at Isabella Dam E. A. Thompson Sacramento District