Concept explainers
At its best efficiency point (η = 0.87), a mixed-flow pump, with D = 16 in., delivers Q = 2500 cfm of water at H = 140 ft when operating at N = 1350 rpm. Calculate the specific speed of this pump. Estimate the required power input. Determine the curve-fit parameters of the pump performance curve based on the shutoff point and the best efficiency point. Scale the performance curve to estimate the flow, head, efficiency, and power input required to run the same pump at 820 rpm.
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
Mechanics of Materials (10th Edition)
Engineering Mechanics: Statics
Heating Ventilating and Air Conditioning: Analysis and Design
Fundamentals Of Thermodynamics
Introduction to Heat Transfer
Statics and Mechanics of Materials (5th Edition)
- Water at 20"C Bows through the pump impeller shown in the figure below, where the inner and outer diameters of the impeller are 160 mm and 400 mm respectively, and the width of the pump blades is 55 mm Part A Wan- μA Estimate the shaft power required to drive the pump at this operating condition Express your answer to three significant figures and include appropriate units. Value Blade Pump impeller The impeller rotates at 3600 rpm Under a particular operating condition, water enters in a direction normal to the inflow surface, the component of the outflow velocity normal to the outflow surface. V is equal to 17 m/s, and the magnitude of the absolute velocity, V, at the outflow surface is 33 m/s Submit Request Answer Units Outflow surface Inflow surface ? 160 บท 400 munarrow_forwardTwo centrifugal pumps are connected in series in a given pumping system. Plot total head Δh against capacity Q pump and system curves and determine the operating points for (a) only pump 1 running (b) only pump 2 running (c) both pumps running on the basis of the following data: operating data for pump 1 Δh1 m, 50.0 49.5 48.5 48.0 46.5 44.0 42.0 39.5 36.0 32.5 28.5 Q m3 /h, 0 25 50 75 100 125 150 175 200 225 250 operating data for pump 2 Δh2 m, 40.0 39.5 39.0 38.0 37.0 36.0 34.0 32.0 30.5 28.0 25.5 Q m3 /h, 0 25 50 75 100 125 150 175 200 225 250 data for system Δhs m, 35.0 37.0 40.0 43.5 46.5 50.5 54.5 59.5 66.0 72.5 80.0 Q m3 /h, 0 25 50 75 100 125 150 175 200 225 250arrow_forwardA 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) approxi-mate 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 unitis 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 ft.arrow_forward
- A certain centrifugal pump was tested and its performance curves can be approximated as follows: H = 340 - 1.2(Q2), in feet BP = (0.0521Q3) + (1.25Q2) + (11.042Q) + 134.5, in horsepower where Q is in ft3/s. If two of this pump is connected in series to deliver water to a system whose head requirement is 615 ft, what will be the operating discharge rate in ft3/s of either pumps?arrow_forwardLen is asked to design a small water pump for an aquarium. The pump should deliver 18.0 Lpm of water at a net head of 1.6 m at its best efficiency point. A motor that spins at 1200 rpm is available Suppose the pump is modified by attaching a different motor, for which the rpm is 1800 rpm. If the pumps operate at homologous points (namely, at the BEP) for both cases, predict the volume flow rate and net head of the modified pump. Calculate the pump specific speed of the modified pump, and compare to that of the original pump. Discuss.arrow_forwardA certain centrifugal pump was tested and its performance curves can be approximated as follows: H = 340 - 1.2(Q2), in feet BP = (0.0521Q3) + (1.25Q2) + (11.042Q) + 134.5, in horsepower where Q is in ft3/s. If two of this pump is connected in series to deliver water to a system whose head requirement is 615 ft, what will be the operating discharge rate in ft3/s of either pumps? Assuming the head is equally divided between the two pumps, what is the efficiency of either pumps (in %)? Take the specific weight of water to be 62.4 lbf/ft3.arrow_forward
- Refer to the “composite performance chart” for a Goulds 3x4-10centrifugal pump operating at 1750 rpm. It shows the pump performance curve for 5 differentimpeller sizes, but also shows the HP required, efficiency, and NPSH required at differentoperating points.Describe the performance of this pump, using an 8 inch impeller and a required flow rate of175 gpm. Give head available, power required (BHP), efficiency, and NPSH req’d. What is the water horsepower (WHP)?arrow_forwardThis course EHide block A centrifugal pump with the following impeller dimensions is used to pump water. The pump is running at 1000 rpm. The ideal head rise through the pump is 190 ft. b2 Poz 72 by The parameters of the impeller are as follows: r2= 9in, b2=3in, B2= 31° Take g= 9.81 m/s23 32.2 ft/s2 pw = 998 kg/m3 = 1.94 Slug/ft. Determine the theoretical flow rate in gpm Choose.. Determine the theoretical Power shaft in (hP) Choose...arrow_forwardGiven: Two (2) identical pumps connected in parallel has the following data: Suction Pressure = 315 KPA Discharge Pressure = 220mmHg Suction Pipe Dia = 390mm Discharge pipe Dia = 405mm Velocity of Water = 6.0 m/s Solve: Total Head, Pump1 & 2 individual head and if Pump 2 is 9.5% less than Pump 1 and Q₁ = Total Flow Ratearrow_forward
- Displacement (c): 0.2 in3/revShank diameter (d) = 0.625 in.Piston diameter (D) = 1.5 in.Rotation speed (n): 1725 RPMPressure (P): 600 PSIStroke (L) = 18in. a) Calculate the theoretical flow rate of the pump in in3/min and US GPM.Theoretical flow (Q) = Theoretical displacement (C) x Speed of revolution (n)Theoretical flow (Q) = 0.2 in3/rev x 1725 rpmTheoretical flow (Q) = 345 in3/min = 1.49 US GPM b) Calculate the cylinder output speed in in/s.Cylinder output speed (VS) = Piston side flow (Q) / Piston area (Ap)Cylinder output speed (VS) = (Displacement x Speed of revolution) / Piston area (Ap)Cylinder output speed (VS) = (0.2 in3/rev x 1725 RPM) / 1.77 in2Cylinder output speed (VS) = (0.2 in3/rev x 1725 RPM) / 1.77 in2Cylinder output speed (VS) = 196.02in/s = 196.02 / 60s = 3.20 in/s Questions: c) Knowing the output velocity (ram speed), calculate the rod side flow in GPM when the ram is extending. d) Calculate the piston exit time in seconds. e) Calculate the piston entry time in…arrow_forwardGiven: Two (2) identical pumps connected in parallel has the following data: Suction Pressure =220mmHg Discharge Pressure = 315 KPA Suction Pipe Dia = 390mm Discharge pipe Dia = 405mm Velocity of Water = 6.0 m/s Solve: Total Head, Pump1 & 2 individual head and if Pump 2 is 9.5% less than Pump 1 and QT = Total Flow Ratearrow_forwardA radial flow pump operating at maximum efficiency at a specific speed of 2300 is to deliver 260gpm against a head of 129ft at a rotative speed of 2100 rpm. Find the required number of stages. ANSWER: 3arrow_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