Concept explainers
Francis turbine Units 19, 20, and 21, installed at the Grand Coulee Dam on the Columbia River, are very large [55]. Each runner is 32.6 ft in diameter and contains 550 tons of cast steel. At rated conditions, each turbine develops 820,000 hp at 72 rpm under 285 ft of head. Efficiency is nearly 95 percent at rated conditions. The turbines operate at heads from 220 to 355 ft. Calculate the specific speed at rated operating conditions. Estimate the maximum water flow rate through each turbine.
Want to see the full answer?
Check out a sample textbook solutionChapter 10 Solutions
Fox and McDonald's Introduction to Fluid Mechanics
Additional Engineering Textbook Solutions
Introduction To Finite Element Analysis And Design
Applied Statics and Strength of Materials (6th Edition)
Introduction to Heat Transfer
Fundamentals of Heat and Mass Transfer
Statics and Mechanics of Materials (5th Edition)
Engineering Mechanics: Statics
- A Kaplan turbine has the following specifications: H =25 ft., N= 400 rpm; power = 650 hp. If the efficiency of the unit is 90%, estimate (a) the flow rate, (b) approximate diameter of the runner, (c) turbine setting to avoid cavitation if the location is at sea level, and (d) turbine setting to avoid cavitation if the location of the unit is at an elevation of 5000 ft. The local temperature is 60°F. Ans: (a) Q=254 cfs; (c) Hs= 5.8 ft.; (d) 0.12 ftarrow_forwardAsaparrow_forwardfri a Peloton turbine, the wheel diameter is 2 m and the deneeting angle of the waer is 162". The jet diameter is 165 mm. the water pressure at the nozzle is 1000 kpa and the discharge correction is not necessary. The wheel rotates at 320 rpm. Neglecting friction, find; (a) the power developed by the wheel, (b) turbine efficiency and (c) wasted water energyarrow_forward
- ima Q1/ An inward flow turbine with radial discharge has an overall efficiency of 80% and develops 150 kw. The head is 8 m and the peripheral velocity at inlet is 0.9√/2gH and flow velocity is 0.36/2gH. The runner speed is 150 rpm: the hydraulic efficiency is 85%. If there is no leakage. determine (a) velocity of whirl at inlet. (b) diameter of the wheel at inlet. (c) flow rate and (d) guidearrow_forwardA Pelton wheel develops 12,900kW at 425rpm under a head of 505m. The efficiency of the machine is 84%. Find (1) discharge of the turbine, (2) diameter of the wheel, and (3) diameter of the nozzle. Assume Cv = 0.98, and ratio of bucket speed to jet speed ¼ 0.46 Draw the schematic diagram and full solution showing formulas use.arrow_forwardHow Vt=Vr × sin (70°) ? i need explanation regarding it. Please provide a solution within 10-20minarrow_forward
- A Pelton wheel works under a net head of 300 meters at a speed of 550 rpm developing 5890 kW of shaft power. The overall efficiency of the turbine is 60%. The ratio of jet diameter to the mean bucket circle diameter is 1/10. Find the number of jets, their diameter, the diameter of the turbine and the quantity of water supplied to the turbine. Assume C, 0.97 and bucket speed = 0.47 jet speed. %3D %3Darrow_forwardPlease solve correctlyarrow_forwardUsing data given below, determine the main dimensions and blade angles of a Francis turbine. Net head=65 m, speed%3 700 rpm, BHP= 400. Actual hydraulic efficiency= 94%, overall efficiency= 85%, flow ratio= 0.18, wheel width at inlet/ wheel diameter at inlet=0.1, inner diameter/ outer diameter= 0.5. Assuming constant velocity of flow and radial discharge. Neglect area blocked by blades. Vane angle at inlet:arrow_forward
- A two stage centrifugal pump is designed to discharge water at a total head of 70 m with an overallefficiency of 0.76. The pump runs at 2331.6 rpm. The actual head developed (per stage) is 65% ofthe theoretical head. The flow at the inlet is pure radial. The impeller at the exit has a diameter of D2=0.219m and a width b2=0.0216m .The outlet blade angle is ?= 28°. Determine:1. The flow rate of the pump.2. The output power of the two stage centrifugal pump. Take ρ= 1000kg/m^3g=9.81 m^2/sarrow_forward[5] A Francis turbine operates at its maximum efficiency point at h0 = 0.94, corresponding to a power specific speed of 0.9 rad. The effective head across the turbine is 160 m and the speed required for electrical generation is 750 rev/min. The runner tip speed is 0.7 times the spouting velocity, the absolute flow angle at runner entry is 70 deg from the radial direction and the absolute flow at runner exit is without swirl. Assuming there are no losses in the guide vanes and the mechanical efficiency is 100%, determine (i) the turbine power and the volume flow rate; (ii) the runner diameter; (iii) the magnitude of the tangential component of the absolute velocity at runner inlet; (iv) the axial length of the runner vanes at inlet.arrow_forwardA Pelton wheel works at the foot of a dam because of which the head available at the nozzle is 400 m. The nozzle diameter is 160 mm and the coefficient of velocity is 0.98, The diameter of the wheel bucket circle is 1.75 m and the buckets deflect the jet by 150°. The wheel-to-jet speed ratio is 0.45. Neglecting riction, calculate (1) the power developed by the turbine, (i) its speed and (i) hydraulic efficiency.arrow_forward
- Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University PressMechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSONThermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
- Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEYMechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage LearningEngineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY