41.5 Case Study: Dam Break Analysis for Kali River Basin

Transcription

1 41.5 Case Study: Dam Break Analysis for Kali River Basin Kali River is a small River originates in Western Ghats at an elevation of about 9 m and flows down for about 16 Km before joining Arabian sea. Kali River has very steep head slopes. It has a catchment of 4428 sq.km. Series of dams have been constructed to develop hydropower project. Typical cross sections are shown in the figure. From the safety point of view the dam break analysis was carried out by Mahesh Kumar and Thandaveswara in 1992 using Mac Cormack Finite Difference scheme. The typical results are shown in figure. One of the very interesting situations is the flow reaches super critical flow conditions in rapids and moving hydraulic jump occurs (in time) Chainage in 'm' C/S at 46th Km (n =.127) Kali River Plan Numbers indicate the Chainage Chainage in 'm' Chainage in 'm' Chainage in 'm' C/S at 47th Km C/S at 48th Km C/S at 49th Km (n =.12) (n =.125) (n =.125)

2 Chainage in 'm' Chainage in 'm' Chainage in 'm' C/S at 5th Km C/S at 51st Km C/S at 52 nd Km (n =.155) (n =.182) (n =.182) Q = 2, cumec Q = 17, cumec 13 5 Chainage in 'm' C/S at 53rd Km (n =.167) Typical cross sections of Kali river Nagjhari Power House Distance in Km Kali River: Bed profile of the river along its course upto Kadra dam location

3 Distance in Km Saddle dam 2 to Nala Junction Note: The channel is Nala from to 1 km and thenon Kaneri river Distance in Km Saddle dam 1 to Kali river: Bed profile of the channel

4 16.15 Mm m 1 m3 /s Upper Kaneri Dam 3758 Mm m Supa Dam PH Km (Starting) Mm 3 2 * 77.5 m 3 /s 99.1 m 3 /s m 83.9 Mm 3 Tattihalla Dam M BP Dam 31.6 Km 43 Km PH Tattihalla River 55.6 Km 6 * 43.5 m 3 /s 62 Km Kaneri River Kali River Mm m PH Kodasalli Dam 82 Km 29.6 Mm3 Constructed 29.6 Mm 3 Under Construction 34.5 m Diversion of flow Kadra Dam 15.8 Km PH Net storage is shown in Mm 3 Arabian Sea Schematic diagram of Karnataka Hydro Electric Project - Stages I and II Supa Dam Bommanahalli Pickup Dam

5 Tattihalla Dam Upper Kaneri Dam Reservoir Inflow Hydrographs

6 Inflow peak = 6629 cumecs (with 1.25 times PMF) Outflow peak = 6173 cumecs for Saddle 1 Outflow peak = 6237 cumecs for Saddle Inflow : Supa Outflow : Supa Outflow : Saddle 1 Outflow : Saddle Inflow Outflow peak 1468 m 3 /s (Supa Dam) Supa Dam: Inflow and Outflow Hydrographs (MWL = initial reservoir level) (outflow from Supa, Saddle 1 and Saddle 2: Breach = 1 hour)

7 m 3 /s (Outflow peak) m 3 /s (Inflow peak) Inflow Breach outflow Bommanahalli pickup dam breach: Inflow and outflow hydrographs

8 m 3 /s (inflow Peak) 6569 m 3 /s (Outflow peak) 5 4 Outflow Inflow Saddle dam number 2 breach: Outflow Hydrograph at 8th km Reference 1. Mahesh Kumar D.V., "Dam-break analysis for Kali River Basin", M.Tech Thesis, Department of Civil Engineering, IIT - Madras, Jan 1992 under the guidance of Prof. B.S.Thandaveswara. 2. Thandaveswara B.S. and Mahesh Kumar D.V. "Dam Break Analysis using Mac Cormack Scheme for Kali River, International Conference On Dam Egg Jahore, Behru Malaysia, January 1993.