1 - Alaska Energy Data Inventory

the type of pipe to be used at Crater Lake. This shows that the RPL givesa more conservative value than the VKP formula when steel pipe is beingconsidered.d Summary. The portion of the above discussion involving frictionfactors in concrete linea pipe could very well be considered an acadelTlicexercise because of the relatively short lengths of tunnel involved (100 ftto 200 ft) and the small differences in the friction factors that wereobtained between the two methods that are being compared. Friction factorsin the penstock however, are of greater significance and it can be seenthat the RPL gives a more conservative value of friction factor than theVKP formula when large steel pipes are being considered. It should be keptin mind that the maximum losses are used to determine minimum pressuregradients and maximum discharges, and the more conservative values are feltto be appropriate here.(5) Minor Losses in the Power Conduit - Calculations for minorlosses included bends, contractions, expansions, slots, tees, trashracksetc. Detailed calculations for minor losses were initially performed for al2-ft power tunnel and a 6-ft penstock which was the power conduit for theDM-23, vented surge tank alternate. The percentages of minor losses withrespect to friction losses for these conduit sizes appear below:Ratio of Minor Losses to Friction LossesCond itionMinimum LossesExpected LossesMaximum LossesIntake toSurge Tank13%24%30%Penstock Entranceto Turbine2.3%3.0%2.8%Friction losses were accurately calculated for each of the differentpower conduits investigated for the economic diameter study. The frictionlosses were then multiplied by the appropriate above percentages, and thesevalues were added to the friction losses to obtain the total hydrauliclosses for each condu it size that was bei ng cons i dered in the economi cdiameter study (see figure 7 in Appendix B2).Bl-2l