Fox and McDonald's Introduction to Fluid Mechanics
9th Edition
ISBN: 9781118912652
Author: Philip J. Pritchard, John W. Mitchell
Publisher: WILEY
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Textbook Question
Chapter 9, Problem 5P
A student is to design an experiment involving dragging a sphere through a tank of fluid to illustrate (a) “creeping flow” (ReD < 1) and (b) flow for which the boundary layer becomes turbulent (ReD ≈ 2.5 × 105). The student proposes to use a smooth sphere of diameter 1 cm in SAE 10 oil at room temperature. Is this realistic for both cases? If either case is unrealistic, select an alternative reasonable sphere diameter and common fluid for that case.
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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. 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