Concept explainers
The water needs of a small farm are to be met by pumping water from a well that can supply water continuously at a rate of 5 L/s. The water level in the well is 20 m below the around level, and water is to be pumped to large tank on a hill, which is 58 m above the ground level of the well, using 6-cm internal diameter plastic pipes. The required length of piping is measured to be 510 in. and the total minor loss coefficient due to the use of elbows, vanes, etc. is estimated to be 12. Taking the efficiency of the pump to be 75 percent, determine the rated power of the pump that needs to be purchased, in kW. The density and viscosity of water at anticipated operation conditions are taken to be 1000 kgm3 and 0.00131 kg/m.s, respectively. Is it wise to purchase a suitable pump that meets the total power requirements, or is it necessary to also pay particular attention to the large elevation head in this case? Explain. Answer: 6.89kW
Want to see the full answer?
Check out a sample textbook solutionChapter 8 Solutions
Fluid Mechanics Fundamentals And Applications
Additional Engineering Textbook Solutions
Heating Ventilating and Air Conditioning: Analysis and Design
Engineering Mechanics: Statics
Vector Mechanics for Engineers: Statics and Dynamics
Vector Mechanics for Engineers: Statics and Dynamics
Foundations of Materials Science and Engineering
Fundamentals of Heat and Mass Transfer
- Water is pumped through a 60-m-long, 0.3 –m-diameter pipe from a lower reservoir to a higher reservoir whose surface is 10 m above the lower one. The sum of the minor loss coefficients for the system is Kl = 1.5. When the pump adds 40 kW to the water the flowrate is 0.2 m3/s. Determine the pipe roughness.arrow_forwardIn a hydroelectric power plant, water at 20°C is supplied to the turbine at a rate of 0.55 m3/s through a 200-m-long, 0.35-m-diameter cast iron pipe. The elevation difference between the free surface of the reservoir and the turbine discharge is 140 m, and the combined turbine–generator efficiency is 85 percent. Disregarding the minor losses because of the large length-to-diameter ratio, determine the electric power output of this plant.arrow_forwardWhich has a greater minor loss coefficient during pipe flow: gradual expansion or gradual contraction? Why?arrow_forward
- Water at 15°C is to be discharged from a reservoir at a rate of 18 L/s using two horizontal cast iron pipes connected in series and a pump between them. The first pipe is X= 5 m long and has a 6-cm diameter, while the second pipe is 5 m long and has a 4-cm diameter. The water level in the reservoir is 30 m above the centerline of the pipe. The pipe entrance is sharp-edged, and losses associated with the connection of the pump are negligible. Neglecting the effect of the kinetic energy correction factor, determine the required pumping head and the minimum pumping power to maintain the indicated flow rate. (The density and dynamic viscosity of water at 15°C are ρ = 999.1 kg/m3 and μ = 1.138x10-3 kg/m.s. The loss coefficient is KL = 0.5 for a sharp-edged entrance. The roughness of cast iron pipes is ε= 0.00026 m.)arrow_forwardWater at 20°C is to be pumped from one tank (ZA=5 m) to another tank at a higher elevation (ZB=13 m) through two 36 m long pipes connected in parallel, as shown in the figure. . The pipes are made of commercial steel, and the diameters of the two pipes are 4 and 8 cm. Water will be pumped via a 70 percent efficient motor-pump coupling that extracts 8 kW of electrical power during operation. Minor losses and head loss in the pipes connecting the pipe joints parallel to the two tanks are considered negligible. Determine the total flow rate between the reservoirs and the flow rate through each of the parallel pipes. Hypothesis: 1.The flow is stationary and incompressible. 2. The input elects are negligible and therefore the flow is fully developed. 3. The elevation of deposits remains constant. 4. Minor losses and head loss in pipes other than parallel pipes are said to be negligible. 5. The flows through both pipes are turbulent (to be verified).arrow_forwardTwo reservoirs are connected by a pipe whose total length is 36 m as shown in Figure 2. From the upper reservoir, the pipe is 250 mm in diameter for a length of 12 m and the remaining 24 m are 125 mm in diameter. The entrance of the pipe is a square-edge inlet and the change of section is sudden. The difference in levels of the water in the two reservoirs is 10 m. The friction coefficient, f, is 0.06 for both pipes and the loss coefficient, K, for sudden contraction is 0.3. Determine the flow rate in the system. Type of losses:Entrance loss (square edge inlet)Friction loss due to pipe 1 (f=0.06)Sudden contraction (K=0.3)Friction loss due to pipe 2 (f=0.06)Exit loss (K=1.0)arrow_forward
- Water is being pumped from a reservoir with water surface elevation of 12 m to another reservoir at elev. 69 m at the rate of 25 L/s. The pump is located at elevation 2 m. The pipe leading from the lower reservoir to the suction side of the pump has Manning’s n=0.011 and is 15 m long and 250 mm in diameter. The pipe from the discharge side of the pump to the upper reservoir is 600 m long and 200 mm in diameter with a friction factor f=0.02. Determine the horsepower required by the pump if its efficiency is 70%.arrow_forwardWater at 60°F (? = 62.36 lbm/ft3 and ? = 7.536 × 10−4 lbm/ft·s) is flowing steadily in a 2-in-diameter horizontal pipe made of stainless steel at a rate of 0.2 ft3/s. Determine the pressure drop, the head loss, and the required pumping power input for flow over a 200-ft-long section of the pipe.arrow_forwardWater in a partially filled large tank is to be supplied to the roof top, which is 8 m above the water level in the tank, through a 2.5-cm-internal-diameter pipe by maintaining a constant air pressure of 300 kPa (gage) in the tank. If the head loss in the piping is 2 m of water, determine the discharge rate of the supply of water to the roof top. Ans: 0.00986 m3/s or 9.86L/sarrow_forward
- Two vessels in which the difference of surface levels is maintained constant at 2.4 m are connected by a 75 mm diameter pipeline 15 m long. If the frictional coefficient f may be taken as 0.008, determine the volume rate of flow.?arrow_forwardWater in a partially filled large tank is to be supplied to the rooftop, which is 8 m above the water level inthe tank, through a 2.5 cm internal diameter pipe by maintaining a constant air pressure of 300 kPa (gauge) inthe tank. If the head loss in the piping system is 2 m of water, determine the discharge rate of the supply ofwater to the rooftop in L/s. Show complete solutionarrow_forwardWater is flowing through a circular pipe made of cast iron with a diameter of 26 cm. If Reynolds number is 105. What is the Darcy friction factor?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