Fox and McDonald's Introduction to Fluid Mechanics
9th Edition
ISBN: 9781118912652
Author: Philip J. Pritchard, John W. Mitchell
Publisher: WILEY
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 9, Problem 75P
A rotary mixer is constructed from two circular disks as shown. The mixer is rotated at 60 rpm in a large vessel containing a brine solution (SG = 1:1). Neglect the drag on the rods and the motion induced in the liquid. Estimate the minimum torque and power required to drive the mixer.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
A Savonius rotor can be approximatedby the two open half-tubes in Fig mounted ona central axis. If the drag of each tube is similar to thatin Table 7.2, derive an approximate formula for therotation rate Ω, as a function of U, D, L, and the fluidproperties (ρ, μ).
An airfoil generates a 1200 N/m sectional lift when traveling at 75 m/s at sea level. What is the circulation generated by this airfoil?
A ship is 150 m long and has a wetted area of 5000 m2.If it is encrusted with barnacles, the ship requires 7000 hpto overcome friction drag when moving in seawater at 15 kn and 20°C. What is the average roughness of thebarnacles? How fast would the ship move with the samepower if the surface were smooth? Neglect wave drag.
Chapter 9 Solutions
Fox and McDonald's Introduction to Fluid Mechanics
Ch. 9 - The roof of a minivan is approximated as a...Ch. 9 - A model of a river towboat is to be tested at 1:18...Ch. 9 - For flow over a smooth plate, what approximately...Ch. 9 - A model of a thin streamlined body is placed in a...Ch. 9 - A student is to design an experiment involving...Ch. 9 - A 1 m 2 m sheet of plywood is attached to the...Ch. 9 - The extent of the laminar boundary layer on the...Ch. 9 - Velocity profiles in laminar boundary layers often...Ch. 9 - An approximation for the velocity profile in a...Ch. 9 - Evaluate / for each of the laminar boundary-layer...
Ch. 9 - Evaluate the displacement thickness and the...Ch. 9 - Evaluate the displacement thickness and the...Ch. 9 - A fluid, with density = 1.5 slug/ft3, flows at U...Ch. 9 - Solve Problem 9.13 with the velocity profile at...Ch. 9 - Air flows in a horizontal cylindrical duct of...Ch. 9 - Evaluate the displacement thickness and the...Ch. 9 - Evaluate the displacement thickness and the...Ch. 9 - A laboratory wind tunnel has a test section 25 cm...Ch. 9 - Air flows in the entrance region of a square duct,...Ch. 9 - A flow of 68F air develops in a flat horizontal...Ch. 9 - A flow of air develops in a horizontal cylindrical...Ch. 9 - Using numerical results for the Blasius exact...Ch. 9 - Using numerical results obtained by Blasius (Table...Ch. 9 - Using numerical results obtained by Blasius (Table...Ch. 9 - A smooth flat plate 2.4 m long and 0.6 m wide is...Ch. 9 - Consider flow of air over a flat plate. On one...Ch. 9 - A thin flat plate, L = 9 in. long and b = 3 ft...Ch. 9 - For a laminar boundary layer on a flat plate,...Ch. 9 - Air at atmospheric pressure and 20C flows over...Ch. 9 - A thin flat plate is installed in a water tunnel...Ch. 9 - Assume laminar boundary-layer flow to estimate the...Ch. 9 - Assume laminar boundary-layer flow to estimate the...Ch. 9 - Assume laminar boundary-layer flow to estimate the...Ch. 9 - Prob. 34PCh. 9 - Water at 10C flows over a flat plate at a speed of...Ch. 9 - Use the momentum integral equation to derive...Ch. 9 - A smooth flat plate 1.6 ft long is immersed in 68F...Ch. 9 - Prob. 38PCh. 9 - A developing boundary layer of standard air on a...Ch. 9 - Assume the flow conditions given in Example 9.3....Ch. 9 - A flat-bottomed barge having a 150 ft 20 ft...Ch. 9 - European InterCity Express trains operate at...Ch. 9 - Grumman Corp. has proposed to build a magnetic...Ch. 9 - Repeat Problem 9.32, for an air flow at 80 ft/s,...Ch. 9 - The velocity profile in a turbulent boundary-layer...Ch. 9 - The U.S. Navy has built the Sea Shadow, which is a...Ch. 9 - The two rectangular smooth flat plates are to have...Ch. 9 - Standard air flows over a horizontal smooth flat...Ch. 9 - Air at standard conditions flows over a flat...Ch. 9 - A uniform flow of standard air at 60 m/s enters a...Ch. 9 - A laboratory wind tunnel has a flexible upper wall...Ch. 9 - Air flows in a cylindrical duct of diameter D = 6...Ch. 9 - Perform a cost-effectiveness analysis on a typical...Ch. 9 - Table 9.1 (on the web) shows the numerical results...Ch. 9 - A fluid flow enters the plane-wall diffuser that...Ch. 9 - For flow over a flat plate with zero pressure...Ch. 9 - A flat-bottomed barge, 80 ft long and 35 ft wide,...Ch. 9 - A towboat for river barges is tested in a towing...Ch. 9 - Plot the local friction coefficient cf, the...Ch. 9 - A smooth plate 3 m long and 0.9 m wide moves...Ch. 9 - Resistance of a barge is to be determined from...Ch. 9 - A nuclear submarine cruises fully submerged at 27...Ch. 9 - You are asked by your college crew to estimate the...Ch. 9 - The drag coefficient of a circular disk when...Ch. 9 - A steel sphere of 0.25 in. diameter has a velocity...Ch. 9 - A steel sphere (SG = 7.8) of 13 mm diameter falls...Ch. 9 - A sheet of plastic material 0.5 in. thick, with...Ch. 9 - As part of the 1976 bicentennial celebration, an...Ch. 9 - What constant speed will be attained by a lead (SG...Ch. 9 - Assuming a critical Reynolds number of 0.1,...Ch. 9 - Glass spheres of 0.1 in. diameter fall at constant...Ch. 9 - A rotary mixer is constructed from two circular...Ch. 9 - Calculate the drag of a smooth sphere of 0.3 m...Ch. 9 - Calculate the drag of a smooth sphere of 0.5 m...Ch. 9 - A cylindrical chimney 0.9 m in diameter and 22.5 m...Ch. 9 - The resistance to motion of a good bicycle on...Ch. 9 - Ballistic data obtained on a firing range show...Ch. 9 - A standard marine torpedo is 0.533 m in diameter...Ch. 9 - A large truck has an essentially boxlike body that...Ch. 9 - At a surprise party for a friend youve tied a...Ch. 9 - A 0.5-m-diameter hollow plastic sphere containing...Ch. 9 - A simple but effective anemometer to measure wind...Ch. 9 - The Willis Tower (formerly the Sears Tower) in...Ch. 9 - It is proposed to build a pyramidal building with...Ch. 9 - Calculate the drag forces on a 1/200 scale model...Ch. 9 - A circular disk is hung in an air stream from a...Ch. 9 - A vehicle is built to try for the land-speed...Ch. 9 - An F-4 aircraft is slowed after landing by dual...Ch. 9 - A tractor-trailer rig has frontal area A = 102 ft2...Ch. 9 - A 180hp sports car of frontal area 1.72 m2, with a...Ch. 9 - An object falls in air down a long vertical chute....Ch. 9 - Prob. 99PCh. 9 - A light plane tows an advertising banner over a...Ch. 9 - The antenna on a car is 10 mm in diameter and 1.8...Ch. 9 - Consider small oil droplets (SG = 0.85) rising in...Ch. 9 - Standard air is drawn into a low-speed wind...Ch. 9 - A small sphere with D = 6 mm is observed to fall...Ch. 9 - A tennis ball with a mass of 57 g and diameter of...Ch. 9 - A water tower consists of a 12-m-diameter sphere...Ch. 9 - A cast-iron 12-pounder cannonball rolls off the...Ch. 9 - A rectangular airfoil of 40 ft span and 6 ft chord...Ch. 9 - A rectangular airfoil of 9 m span and 1.8 m chord...Ch. 9 - Why is it possible to kick a football farther in a...Ch. 9 - If CL = 1.0 and CD = 0.05 for an airfoil, then...Ch. 9 - A wing model of 5 in. chord and 2.5 ft span is...Ch. 9 - A barge weighing 8820 kN that is 10 m wide, 30 m...Ch. 9 - A spherical sonar transducer with 15 in. diameter...Ch. 9 - While walking across campus one windy day, an...Ch. 9 - If the mean velocity adjacent to the top of a wing...Ch. 9 - The NACA 23015 airfoil is to move at 180 mph...Ch. 9 - A human-powered aircraft has a gross weight of 240...Ch. 9 - WiffleTM balls made from light plastic with...Ch. 9 - A model airfoil of chord 6 in. and span 30 in. is...Ch. 9 - An antique airplane carries 50 m of external guy...Ch. 9 - How do cab-mounted wind deflectors for...Ch. 9 - An airplane with an effective lift area of 25 m2...Ch. 9 - The U.S. Air Force F-16 fighter aircraft has wing...Ch. 9 - A light airplane, with mass M = 1000 kg, has a...Ch. 9 - A light airplane has 35-ft effective wingspan and...Ch. 9 - Assume the Boeing 727 aircraft has wings with NACA...Ch. 9 - Jim Halls Chaparral 2F sports-racing cars in the...Ch. 9 - Some cars come with a spoiler, a wing section...Ch. 9 - Roadside signs tend to oscillate in a twisting...Ch. 9 - Air moving over an automobile is accelerated to...Ch. 9 - A class demonstration showed that lift is present...Ch. 9 - Rotating cylinders were proposed as a means of...Ch. 9 - A baseball pitcher throws a ball at 80 mph. Home...
Additional Engineering Textbook Solutions
Find more solutions based on key concepts
Why is laser-beam welding an attractive process for producing tailored blanks for sheet metal forming? For use ...
DeGarmo's Materials and Processes in Manufacturing
In each case, construct the parallelogram law to show FR = F1 + F2. Then establish the triangle rule, where FR ...
Statics and Mechanics of Materials (5th Edition)
Determine the normal stress in each member of the truss structure. All joints are ball joint, and the material ...
Introduction To Finite Element Analysis And Design
ICA 10-6
The worksheet provided was designed to calculate the total pressure felt by an object submerged in a f...
Thinking Like an Engineer: An Active Learning Approach (3rd Edition)
8.19 Compute the radii of gyration with respect to the X-X and Y-Y centroidal axes for the aluminum extruded sh...
Applied Statics and Strength of Materials (6th Edition)
An undersea camera (Figure 5.36 ) is to hang from a float in the ocean, allowing it to take constant video of u...
Applied Fluid Mechanics (7th Edition)
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
- If your lift to drag ratio is 15 for airline A flight and the airplane weighs 15,000-lb for L/Dmax, what’s the speed for L/Dmax at 22,500 lbs.?arrow_forwardIcebergs can be driven at substantial speeds by the wind.Let the iceberg be idealized as a large, flat cylinder, D >> L,with one-eighth of its bulk exposed, as in Fig.. Letthe seawater be at rest. If the upper and lower drag forcesdepend on relative velocities between the iceberg and thefluid, derive an approximate expression for the steady icebergspeed V when driven by wind velocity U.arrow_forwardA new sports car has a drag corfficient of 0.30 and a frontal area of 18.5 ft<, and is traveling at 90 mi/h. How much power (in ft-lb/s) is required to overcome aerodynamic drag if air density is 0.002378 slugs/ft?arrow_forward
- A propeller-driven aircraft has an in-flight weight of 4,105 lb (equivalent to a mass of 1,862 kg) and is cruising at a true airspeed of 120 kts. The lift-to-drag ratio of the aircraft is 8.2. If the propeller efficiency, ηp, is 0.8, then how much brake power is required for flight? Work through this problem in both USC and SI units.arrow_forwarda)What is the impact of increasing Reynolds number on skin friction and pressure drags over an airfoil? What can be happened for separation in this case? b) What is an adverse pressure gradient and where does it occur on an airfoil (show that on a sketch)? c) Why lift-to-drag ratio is an important parameter for an aircraft? d)How can changing in altitude affect the aircraft power required, PR? Show thatmathematically and graphically?arrow_forwardName some applications in which a large drag is desired.arrow_forward
- A ship is 125 m long and has a wetted area of 3500 m2.Its propellers can deliver a maximum power of 1.1 MWto seawater at 20°C. If all drag is due to friction, estimatethe maximum ship speed, in kn.arrow_forwardFor those who think electric cars are sissy, Keio University inJapan has tested a 22-ft-long prototype whose eight electricmotors generate a total of 590 horsepower. The “Kaz” cruisesat 180 mi/h (see Popular Science, August 2001, p. 15). If thedrag coefficient is 0.35 and the frontal area is 26 ft2, what percentageof this power is expended against sea-level air drag?arrow_forwardHow do we use the Buckingham pi theorem to prove that drag coefficient is dimensionless?arrow_forward
- The standard sea level value of viscosity coefficient for air is μ = 1.7894×10−5 kg/(m · s) = 3.7373 × 10−7 slug/(ft · s). The wing on a Piper Cherokee general aviation aircraft is rectangular, witha span of 9.75 m and a chord of 1.6 m. The aircraft is flying at cruisingspeed (141 mi/h) at sea level. Assume that the skin-friction drag on thewing can be approximated by the drag on a flat plate of the samedimensions. Calculate the skin-friction drag:a. If the flow were completely laminar (which is not the case in real life)b. If the flow were completely turbulent (which is more realistic)Compare the two results.arrow_forwardEstimate its drag in N. Take CD ≈ 0.4.arrow_forwarda balloon is 4 m in diameter and contains helium at 125 kpa and 15°c. balloon material and payload weigh 200 n, not including the helium. estimate (a) the terminal ascent velocity in sea-level standard air, (b) the final standard altitude (neglecting winds) at which the balloon will come to rest, and (c) the minimum diameter (< 4 m) for which the balloon will just barely begin to rise in sea-level standard air.arrow_forward
arrow_back_ios
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
Unit Conversion the Easy Way (Dimensional Analysis); Author: ketzbook;https://www.youtube.com/watch?v=HRe1mire4Gc;License: Standard YouTube License, CC-BY