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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />Following the reducer would be a 90 degree vertical bend. An <br />upward 10-inch "T" would be in the pipeline after the bend to <br />allow a bypass around the turbine if the turbine is shut down. On <br />each of the downstream legs of the "T" would be a butterfly valve <br />which is automatically controlled so that the valve on the turbine <br />leg is open when the machine is operating and the bypass leg valve <br />is closed. I f the machine stops for some reason, the turbine <br />butterfly valve automatically closes and the butterfly valve on <br />the bypass leg opens. The lO-inch bypass pipe loops above the <br />turbine and "T"'s back into the pipe downstream of the turbine. <br /> <br />The 10-inch pipe would connect to the turbine after the <br />butterfly valve. With this configuration the turbine and genera- <br />tor would be placed on concrete pedestals nearly three feet above <br />the floor of the chamber. The turbine discharge is 14-inches in <br />diameter which is immediately reduced by a 14-inch to 12-inch <br />reducer to match the diameter of the outlet pipe which is 12- <br />inches in diameter. A 12-inch gate valve is located after the <br />reducer and before the intersection with the bypass "T" so that <br />the turbine can be isolated from the bypass pipe. The "T" for the <br />. <br />bypass would be incorporated in the 90 degree downward bend. From <br />the bend the pipe would extend downward until connecting with the <br />existing 12- inch outlet pipe. The head loss through this pipe <br />configuration, expressed as a function of flow is 0.2116Q2 for the <br />inlet and 0.0566Q' for the outlet for a total loss of 0.2682Q'. A <br />15% contingency is added to the calculated loss giving 0.3084Q2. <br />The result is 52 feet of head loss at 13 cfs, which is the maximum <br />flow, and 25 feet of loss at 9 cfs, the lowest flow. <br /> <br />This configuration has the advantage of requiring the least <br />change in the existing piping; however, it has two disadvantages. <br />One disadvantage is the need for a three-foot high concrete <br />pedestal that would be required for the turbine and generator. <br />The other disadvantage is that 10 ft is the maximum elevation the <br /> <br />7.0-5 <br />