Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781259822674
Author: Yunus A. Cengel Dr., Michael A. Boles
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 2.8, Problem 134FEP
To determine
The overall efficiency of the pump.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
A pump is to deliver 80 gpm of water having specific volume of 1.0164x10-3 m3/kg at a temperature of 140°F and discharge pressure of 150 psig.
Suction pressure indicates 2 in.of mercury vacuum. The diameter of suction and discharge pipes are 5 in. and 4 in., respectively. The pump has an
efficiency of 70%, while the motor efficiency is 80%. Determine the power input to drive the motor in horsepower.
When water is pumped into a water tank 20 m above a lake with a flow rate of 70 l/s, 20.4kW of electrical power is consumed. Determine the efficiency of the pump-motor group by ignoring the friction losses in the pipes and the change in kinetic energy. Determine the pressure difference between the inlet and outlet of the pump.
A pump takes water at 60°F from a large reservoir and delivers it to the bottom of an open elevated tank 25 ft above the reservoir surface through a 3 inch ID pipe. The inlet to the pump is located 10 ft below the water surface, and the water level in the tank is constant at 160 ft above the reservoir surface. The pump delivers 150 gal/min. If the total loss of energy due to friction in the piping system is 35 ft·lbf/lb. The pump and its motor have an overall efficiency of 55 %.
answer the ff:
i. Determine the velocity of the water at point 2.
ii. Reynolds number for the flow.
iii. A pump efficiency of 55% means that the theoretical work needed for the process is 55% of the actual work needed. In other words, 55% more shaft work is necessary. Determine the theoretical shaft work required in foot-pound force per pound mass.
Chapter 2 Solutions
Thermodynamics: An Engineering Approach
Ch. 2.8 - What is the difference between the macroscopic and...Ch. 2.8 - What is total energy? Identify the different forms...Ch. 2.8 - List the forms of energy that contribute to the...Ch. 2.8 - How are heat, internal energy, and thermal energy...Ch. 2.8 - What is mechanical energy? How does it differ from...Ch. 2.8 - Portable electric heaters are commonly used to...Ch. 2.8 - Natural gas, which is mostly methane CH4, is a...Ch. 2.8 - Consider the falling of a rock off a cliff into...Ch. 2.8 - Electric power is to be generated by installing a...Ch. 2.8 - The specific kinetic energy of a moving mass is...
Ch. 2.8 - Determine the specific kinetic energy of a mass...Ch. 2.8 - Calculate the total potential energy, in Btu, of...Ch. 2.8 - Determine the specific potential energy, in kJ/kg,...Ch. 2.8 - An object whose mass is 100 kg is located 20 m...Ch. 2.8 - A water jet that leaves a nozzle at 60 m/s at a...Ch. 2.8 - Consider a river flowing toward a lake at an...Ch. 2.8 - At a certain location, wind is blowing steadily at...Ch. 2.8 - What is the caloric theory? When and why was it...Ch. 2.8 - In what forms can energy cross the boundaries of a...Ch. 2.8 - What is an adiabatic process? What is an adiabatic...Ch. 2.8 - When is the energy crossing the boundaries of a...Ch. 2.8 - Consider an automobile traveling at a constant...Ch. 2.8 - A room is heated by an iron that is left plugged...Ch. 2.8 - A room is heated as a result of solar radiation...Ch. 2.8 - A gas in a pistoncylinder device is compressed,...Ch. 2.8 - A small electrical motor produces 5 W of...Ch. 2.8 - A car is accelerated from rest to 85 km/h in 10 s....Ch. 2.8 - A construction crane lifts a prestressed concrete...Ch. 2.8 - Determine the torque applied to the shaft of a car...Ch. 2.8 - A spring whose spring constant is 200 lbf/in has...Ch. 2.8 - How much work, in kJ, can a spring whose spring...Ch. 2.8 - A ski lift has a one-way length of 1 km and a...Ch. 2.8 - The engine of a 1500-kg automobile has a power...Ch. 2.8 - A damaged 1200-kg car is being towed by a truck....Ch. 2.8 - As a spherical ammonia vapor bubble rises in...Ch. 2.8 - A steel rod of 0.5 cm diameter and 10 m length is...Ch. 2.8 - What are the different mechanisms for transferring...Ch. 2.8 - For a cycle, is the net work necessarily zero? For...Ch. 2.8 - On a hot summer day, a student turns his fan on...Ch. 2.8 - Water is being heated in a closed pan on top of a...Ch. 2.8 - An adiabatic closed system is accelerated from 0...Ch. 2.8 - A fan is to accelerate quiescent air to a velocity...Ch. 2.8 - A vertical pistoncylinder device contains water...Ch. 2.8 - At winter design conditions, a house is projected...Ch. 2.8 - A water pump increases the water pressure from 15...Ch. 2.8 - The lighting needs of a storage room are being met...Ch. 2.8 - A university campus has 200 classrooms and 400...Ch. 2.8 - Consider a room that is initially at the outdoor...Ch. 2.8 - An escalator in a shopping center is designed to...Ch. 2.8 - Consider a 2100-kg car cruising at constant speed...Ch. 2.8 - Prob. 51PCh. 2.8 - What is mechanical efficiency? What does a...Ch. 2.8 - How is the combined pumpmotor efficiency of a pump...Ch. 2.8 - Can the combined turbinegenerator efficiency be...Ch. 2.8 - Consider a 2.4-kW hooded electric open burner in...Ch. 2.8 - The steam requirements of a manufacturing facility...Ch. 2.8 - Reconsider Prob. 256E. Using appropriate software,...Ch. 2.8 - A 75-hp (shaft output) motor that has an...Ch. 2.8 - Prob. 59PCh. 2.8 - An exercise room has six weight-lifting machines...Ch. 2.8 - A room is cooled by circulating chilled water...Ch. 2.8 - The water in a large lake is to be used to...Ch. 2.8 - A 7-hp (shaft) pump is used to raise water to an...Ch. 2.8 - A geothermal pump is used to pump brine whose...Ch. 2.8 - At a certain location, wind is blowing steadily at...Ch. 2.8 - Reconsider Prob. 265. Using appropriate software,...Ch. 2.8 - Water is pumped from a lower reservoir to a higher...Ch. 2.8 - An 80-percent-efficient pump with a power input of...Ch. 2.8 - Water is pumped from a lake to a storage tank 15 m...Ch. 2.8 - Large wind turbines with a power capacity of 8 MW...Ch. 2.8 - A hydraulic turbine has 85 m of elevation...Ch. 2.8 - The water behind Hoover Dam in Nevada is 206 m...Ch. 2.8 - An oil pump is drawing 44 kW of electric power...Ch. 2.8 - A wind turbine is rotating at 15 rpm under steady...Ch. 2.8 - How does energy conversion affect the environment?...Ch. 2.8 - What is acid rain? Why is it called a rain? How do...Ch. 2.8 - Why is carbon monoxide a dangerous air pollutant?...Ch. 2.8 - What is the greenhouse effect? How does the excess...Ch. 2.8 - What is smog? What does it consist of? How does...Ch. 2.8 - Consider a household that uses 14,000 kWh of...Ch. 2.8 - When a hydrocarbon fuel is burned, almost all of...Ch. 2.8 - Prob. 82PCh. 2.8 - A typical car driven 20,000 km a year emits to the...Ch. 2.8 - Prob. 84PCh. 2.8 - What are the mechanisms of heat transfer?Ch. 2.8 - Which is a better heat conductor, diamond or...Ch. 2.8 - How does forced convection differ from natural...Ch. 2.8 - What is a blackbody? How do real bodies differ...Ch. 2.8 - Define emissivity and absorptivity. What is...Ch. 2.8 - Does any of the energy of the sun reach the earth...Ch. 2.8 - The inner and outer surfaces of a 5-m 6-m brick...Ch. 2.8 - The inner and outer surfaces of a 0.5-cm-thick 2-m...Ch. 2.8 - Reconsider Prob. 292. Using appropriate software,...Ch. 2.8 - Prob. 94PCh. 2.8 - Prob. 95PCh. 2.8 - Prob. 96PCh. 2.8 - Prob. 97PCh. 2.8 - For heat transfer purposes, a standing man can be...Ch. 2.8 - Prob. 99PCh. 2.8 - Prob. 100PCh. 2.8 - A 1000-W iron is left on the ironing board with...Ch. 2.8 - A 7-cm-external-diameter, 18-m-long hot-water pipe...Ch. 2.8 - A thin metal plate is insulated on the back and...Ch. 2.8 - Reconsider Prob. 2103. Using appropriate software,...Ch. 2.8 - The outer surface of a spacecraft in space has an...Ch. 2.8 - Prob. 106PCh. 2.8 - A hollow spherical iron container whose outer...Ch. 2.8 - Some engineers have developed a device that...Ch. 2.8 - Consider a classroom for 55 students and one...Ch. 2.8 - Consider a homeowner who is replacing his...Ch. 2.8 - Prob. 111RPCh. 2.8 - The U.S. Department of Energy estimates that...Ch. 2.8 - A typical household pays about 1200 a year on...Ch. 2.8 - Prob. 114RPCh. 2.8 - Prob. 115RPCh. 2.8 - Prob. 116RPCh. 2.8 - Consider a TV set that consumes 120 W of electric...Ch. 2.8 - Water is pumped from a 200-ft-deep well into a...Ch. 2.8 - Consider a vertical elevator whose cabin has a...Ch. 2.8 - Prob. 120RPCh. 2.8 - In a hydroelectric power plant, 65 m3/s of water...Ch. 2.8 - The demand for electric power is usually much...Ch. 2.8 - The pump of a water distribution system is powered...Ch. 2.8 - Prob. 124RPCh. 2.8 - A 2-kW electric resistance heater in a room is...Ch. 2.8 - Prob. 126FEPCh. 2.8 - A 75-hp compressor in a facility that operates at...Ch. 2.8 - On a hot summer day, the air in a well-sealed room...Ch. 2.8 - A fan is to accelerate quiescent air to a velocity...Ch. 2.8 - A 900-kg car cruising at a constant speed of 60...Ch. 2.8 - Prob. 131FEPCh. 2.8 - Prob. 132FEPCh. 2.8 - A 2-kW pump is used to pump kerosene ( = 0.820...Ch. 2.8 - Prob. 134FEPCh. 2.8 - Prob. 135FEPCh. 2.8 - Prob. 136FEPCh. 2.8 - Prob. 137FEPCh. 2.8 - Heat is transferred steadily through a...Ch. 2.8 - The roof of an electrically heated house is 7 m...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- A pump takes water at 60°F from a large reservoir and delivers it to the bottom of an open elevated tank 25 ft above the reservoir surface through a 3 inch ID pipe. The inlet to the pump is located 10 ft below the water surface, and the water level in the tank is constant at 160 ft above the reservoir surface. The pump delivers 150 gal/min. If the total loss of energy due to friction in the piping system is 35 ft·lbf/lb. The pump and its motor have an overall efficiency of 55 %. i.Let us set our first point at the surface of the large reservoir, and the second point at the surface of the open elevated tank. Determine the velocity of the water at point 1 in ft/s. ii.What is the density of water at the conditions stated in lb/ft3? iii.If 1 horsepower is equivalent to 500 (ft-lbf)/s, the pump should be able to supply how much hp?arrow_forwardA pump takes water at 60°F from a large reservoir and delivers it to the bottom of an open elevated tank 25 ft above the reservoir surface through a 3 inch ID pipe. The inlet to the pump is located 10 ft below the water surface, and the water level in the tank is constant at 160 ft above the reservoir surface. The pump delivers 150 gal/min. If the total loss of energy due to friction in the piping system is 35 ft·lbf/lb. The pump and its motor have an overall efficiency of 55 %. a. Assuming that the large open reservoir is open to the atmosphere as well, what is the mechanical energy balance eq for the system? b. What is the Reynolds number for the flow ?arrow_forwardThe motor of a pump consumes 1.05 hp of electricity. The pump increases the pressure of water from 120 kPa to 1100 kPa at a rate of 35 L/min. If the motor efficiency is 94 percent, the pump efficiency is (a) 0.75 (b) 0.78 (c) 0.82 (d) 0.85 (e) 0.88arrow_forward
- A pump takes water at 60°F from a large reservoir and delivers it to the bottom of an open elevated tank 25 ft above the reservoir surface through a 3 inch ID pipe. The inlet to the pump is located 10 ft below the water surface, and the water level in the tank is constant at 160 ft above the reservoir surface. The pump delivers 150 gal/min. If the total loss of energy due to friction in the piping system is 35 ft·lbf/lb. The pump and its motor have an overall efficiency of 55 %. i. Determine Delta Z (Z2 - Z1) in ft. ii. What is the actual shaft work needed for this particular mass flow rate in (ft-lbf)/s. iii. What is the mass flow rate of the water in lbm/s?arrow_forwardSeawater is to be pumped into a large tank at a rate of 165 kg/min. The tank is open to the atmosphere and the water enters the tank from an 80 m height. The overall efficiency of the motor pump unit is 75 percent and the motor consumes electricity at a rate of 3.2 KW. If the irreversible headloss in the piping is 7 m, the velocity of the water (in m/s) at the tank inlet is ____. Include the diagram in your solution. A.5.05 B.7.12 C.6.21 D.8.7arrow_forwardA pump is to deliver 80 GPM of water at 1400F (ρ = 61.424 lb/ft3) with a discharge pressure of 150 psig. Suction pressure indicates 2 inches of mercury vacuum. The diameter of the suction and discharge pipes are five (5) inches and four (4) inches, respectively. The pump has an efficiency of 70%, while the motor efficiency is 80%. DETERMINE: 1. Water horsepower of the pump 2. Brake horsepower of the pump 3. Power input to drive the motor 4. Combined motor-pump efficiencyarrow_forward
- A pump takes water at 60°F from a large reservoir and delivers it to the bottom of an open elevated tank 25 ft above the reservoir surface through a 3 inch ID pipe. The inlet to the pump is located 10 ft below the water surface, and the water level in the tank is constant at 160 ft above the reservoir surface. The pump delivers 150 gal/min. If the total loss of energy due to friction in the piping system is 35 ft·lbf/lb, Calculate the horsepower required to do the pumping. The pump and its motor have an overall efficiency of 55 %. i. What is Delta Z (Z2 - Z1) ? in ft. ii. Determine the theoretical shaft work required in foot-pound force per pound mass.. iii.Determine the actual shaft work needed for this particular mass flow rate in (ft-lbf)/s.arrow_forwardA pump takes water at 60°F from a large reservoir and delivers it to the bottom of an open elevated tank 25 ft above the reservoir surface through a 3 inch ID pipe. The inlet to the pump is located 10 ft below the water surface, and the water level in the tank is constant at 160 ft above the reservoir surface. The pump delivers 150 gal/min. If the total loss of energy due to friction in the piping system is 35 ft·lbf/lb, Calculate the horsepower required to do the pumping. The pump and its motor have an overall efficiency of 55 %. i. Determine the velocity of the water at point 2 in ft/s. ii. Assuming that the large open reservoir is open to the atmosphere as well, which of the following equations best describes the mechanical energy balance for the system? iii.The Reynolds number for the flow is?arrow_forwardAn adiabatic pump is used to increase the pressure of water from 100 kPa to 500 kPa at a rate of 400 L/min. If the efficiency of the pump is 75 percent, the maximum temperature rise of the water across the pump is (a) 0.096° C (b) 0.058° C (c) 0.035° C (d ) 1.52° C (e) 1.27° Carrow_forward
- The minimum power needed by a water pump that increases the pressure of 4 kg/s from 100 kPa to 6 MPa is nearestarrow_forwardThe pump of a water distribution system is powered by a 15-kW electric motor whose efficiency is 90 percent. The water flow rate through the pump is 50 L/s. The diameters of the inlet and outlet pipes are the same, and the elevation difference across the pump is negligible. If the absolute pressures at the inlet and outlet of the pump are measured to be 100 kPa and 300 kPa, respectively, determine (a) the mechanical efficiency of the pump and (b) the temperature rise of water as it flows through the pump due to mechanical inefficiencies.arrow_forwardThe pump of a water distribution system is powered by a 15-kW electric motor whose efficiency is 90 %. The water flow rate through the pump is 50 L/s. The diameters of the inlet and outlet pipes are the same, and the elevation difference across the pump is negligible. If the absolute pressures at the inlet and outlet of the pump are measured to be 100 kPa and 300 kPa, respectively, determine: (a) the mechanical efficiency of the pump (b) the temperature rise of water as it flows through the pump due to mechanical inefficiencies. 300 kPa 100 kPa 1 Water 450 L/s ① W. pump nmotor = 90% Motor 15 kWarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- 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
Elements Of Electromagnetics
Mechanical Engineering
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Oxford University Press
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:9780134319650
Author:Russell C. Hibbeler
Publisher:PEARSON
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:9781259822674
Author:Yunus A. Cengel Dr., Michael A. Boles
Publisher:McGraw-Hill Education
Control Systems Engineering
Mechanical Engineering
ISBN:9781118170519
Author:Norman S. Nise
Publisher:WILEY
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:9781337093347
Author:Barry J. Goodno, James M. Gere
Publisher:Cengage Learning
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:9781118807330
Author:James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:WILEY
Fluid Mechanics - Viscosity and Shear Strain Rate in 9 Minutes!; Author: Less Boring Lectures;https://www.youtube.com/watch?v=_0aaRDAdPTY;License: Standard youtube license