the

length of the outlet tunnel, \( \mathrm{L}_{2} \), is unknown. But the outlet tumel is made of spray lined concrete that has a friction factor of 0.012 . In the spiral a maximum pressure of 56 bar was recorded during the load rejection. Th a) The flow of water during the load rejection. b) The power of the station before the load rejection happened. c) The length of the tunnel.

13. During a load rejection in the power plant illustrated in the figure below. The elevation in the surge tank varied sinusoidally with a maximum rate of change of 9.55 m/s. h h 12 hz The chief engineer has found data on the outlet tunnel area and the surge cavern area, being 75 m and 7.5 m respectively. Unfortunately the length of the outlet tunnel, L2, is unknown. But the outlet tunnel is made of spray lined concrete that has a friction factor of 0.012. In the spiral a maximum pressure of 56 bar was recorded during the load rejection. The stationary levels at the positions indicated by h was +280 masl, h was +130 masl, and hy was +128 masl. Help the chief engineer to calculate: a) The flow of water during the load rejection. b) The power of the station before the load rejection happened. c) The length of the tunnel. (10p)