Fluid Mechanics: Fundamentals and Applications
4th Edition
ISBN: 9781259877827
Author: CENGEL
Publisher: MCG
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Chapter 5, Problem 11P
A desktop computer is to be cooled by a fan whose flow rate is 0.30 m3/min. Determine the mass flow rate of air through the fan at an elevation of 3400 m where the air density is 0.7 kg/m3. Also, if the average velocity of air is not to exceed 95 m/min, determine the minimum diameter of the casing of the fan.
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Air at a static temperature and pressure of 9°C and 100 kPa respectively enters the intake of an aircraft gas turbine engine with a velocity of 206 m/s. The intake may be regarded as a diffuser with an inlet area of 0.4 m2 and an exit area that reduces the air flow velocity essentially to zero. Calculate the mass flow rate (kg/s) of air through the intake, given the specific gas (air) constant as 287 J/(kg.K)
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Note that Air Power of the fan is give by: AP = Qy Ah
Where: Q = volume flow rate of air m3/s, y = specific weight of air, kN/m³, Ah = pressure head, m
Ans: 618 mm
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Chapter 5 Solutions
Fluid Mechanics: Fundamentals and Applications
Ch. 5 - Does the amount of mass entering a control volume...Ch. 5 - Define mass and volume flow rates. How are they...Ch. 5 - Name four physical quantities that are conserved...Ch. 5 - When is the flow through a control volume steady?Ch. 5 - Consider a device with one inlet and one outlet....Ch. 5 - A hair dryer is basically a duct of constant...Ch. 5 - A garden hose attached with a nozzle is used to...Ch. 5 - Air whose density is 0.082 Ibm/ft3 enters the duct...Ch. 5 - A 0.7$-m3 rigid tank initially contains air whose...Ch. 5 - Consider the flow of an incompressible Newtonian...
Ch. 5 - A desktop computer is to be cooled by a fan whose...Ch. 5 - The minimum fresh air requirement of a residential...Ch. 5 - The ventilating fan of the bathroom of a building...Ch. 5 - Air enters a nozzle steadily at 2.21 kg/m3 and 20...Ch. 5 - Air at 40°C flow steadily through the pipe shown...Ch. 5 - In climates with low night-time temperatures, an...Ch. 5 - What is mechanical energy? How does it differ from...Ch. 5 - Define turbine efficiency, generator efficiency,...Ch. 5 - What is mechanical efficiency? What does a...Ch. 5 - How is the combined pump-motor efficiency of a...Ch. 5 - Prob. 21PCh. 5 - A differential thermocouple with sensors at the...Ch. 5 - Electric power is to be generated by installing a...Ch. 5 - Consider a river flowing toward a lake at an...Ch. 5 - Express the Bernoulli equation in three different...Ch. 5 - What are the three major assumptions used in the...Ch. 5 - Define static, dynamic, and hydrostatic pressure....Ch. 5 - What is streamwise acceleration? How does it...Ch. 5 - What is stagnation pressure? Explain how it can be...Ch. 5 - Define pressure head, velocity head, and elevation...Ch. 5 - How is the location of the hydraulic grade line...Ch. 5 - Prob. 33CPCh. 5 - What is the hydraulic grade line? 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Is...Ch. 5 - The water level in a tank is 20 m above the...Ch. 5 - A 3-rn-high tank filled with water has a discharge...Ch. 5 - A person is filling a knee-high bucket with water...Ch. 5 - Tater is being pumped from a large lake to a...Ch. 5 - A 15-hp (shaft) pump is used to raise water to a...Ch. 5 - Water flows at a rate of 0.040 m3/s in a...Ch. 5 - The water level in a tank is 20 m above the...Ch. 5 - A hydraulic turbine has 50 m of head available at...Ch. 5 - In a hydroelectric power plant, water flows from...Ch. 5 - Reconsider Prob. 5-78E. Determine the flow rate of...Ch. 5 - A fan is to be selected to ventilate a bathroom...Ch. 5 - Water flows at a rate of 20 L/s through a...Ch. 5 - The water level in a tank is 34 ft above the...Ch. 5 - A large tank is initially filled with water 4 m...Ch. 5 - Water enters a hydraulic turbine through a...Ch. 5 - A 78-percent efficient 12-hp pump is pumping water...Ch. 5 - Water is pumped from a lower reservoir to a higher...Ch. 5 - Water in a partially filled large tank is to be...Ch. 5 - Underground water is to be pumped by a 78 percent...Ch. 5 - Reconsider Prob. 5-88. Determine the flow rate of...Ch. 5 - The velocity profile for turbulent flow in a...Ch. 5 - The demand for electric power is usually much...Ch. 5 - Prob. 92PCh. 5 - Consider a fully filled hemisphere shaped tank...Ch. 5 - The velocity of a liquid flowing in a circular...Ch. 5 - Air at 250 kgrn3 enters a nozzle that has an...Ch. 5 - The air in a 5m5-m3-m hospital room is to be...Ch. 5 - The water level in a tank is 70 ft above the...Ch. 5 - A pressurized 2-rn-diameter tank of water has a...Ch. 5 - Underground water is being pumped into a pool...Ch. 5 - Prob. 100PCh. 5 - A very large tank contains air at 102 kPa at a...Ch. 5 - Water is flowing through a Venturi meter whose...Ch. 5 - Water flows at a rate of 0.011 m3/s in a...Ch. 5 - Air flows through a pipe at a rate of 120 L/s. The...Ch. 5 - A 3-rn-high large tank is initially filled with...Ch. 5 - Reconsider Prob. 5-105. In order to dram the tank...Ch. 5 - A D0= 1 2-rn-diameter tank is initially filled...Ch. 5 - An oil pump is drawing 18 kW of electric power...Ch. 5 - A wind tunnel draws atmospheric air at 20°C and...Ch. 5 - Consider a spherical tank containing compressed...Ch. 5 - A tank with openings 1,2, and 3 is moving to left...Ch. 5 - Two dimensionally identical containers are...Ch. 5 - A circular thin plate is placed on the top of a...Ch. 5 - A pump-storage plant uses a turbine to generate...Ch. 5 - A diffuser in a pipe flow is basically a slow...Ch. 5 - Prob. 117PCh. 5 - Prob. 118PCh. 5 - Prob. 119PCh. 5 - Air enters a steady-flow compressor at 1 atm and...Ch. 5 - A 7$-m-high water body that is open to the...Ch. 5 - Prob. 122PCh. 5 - Prob. 123PCh. 5 - A hydraulic turbine is used to generate power by...Ch. 5 - The efficiency of a hydraulic turbine-generator...Ch. 5 - Which one is not an assumption involved with the...Ch. 5 - Consider incompressible, frictionless flow of a...Ch. 5 - Consider incompressible, frictionless flow of...Ch. 5 - Consider water flow in a piping network. 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