Fox and McDonald's Introduction to Fluid Mechanics
Fox and McDonald's Introduction to Fluid Mechanics
9th Edition
ISBN: 9781118912652
Author: Philip J. Pritchard, John W. Mitchell
Publisher: WILEY
bartleby

Videos

Textbook Question
Chapter 9, Problem 1P

The roof of a minivan is approximated as a horizontal flat plate. Plot the length of the laminar boundary layer as a function of minivan speed, V, as the minivan accelerates from 10 mph to 90 mph.

Expert Solution & Answer
Check Mark
To determine

The plot of the length of the laminar boundary versus minivan speed.

Explanation of Solution

Given:

The initial speed of the minivan (V1) is 10mph.

The final speed of the minivan (V2) is 20mph.

Calculation:

The Reynolds number for the laminar boundary layer is 5×105.

Refer the appendix, Table A.9 “Properties of Air at Atmospheric Pressure (U.S. Customary Units)” for the temperature of 68°F.

  μ=3.379×107 lbfs/ft2×5ρ=0.00234 slugs/ft3

Calculate the expression for the length of the laminar boundary layer using the Reynolds number (Re).

  Re=ρVLμL=ReμρV

Substitute the known values in the above Equation.

  L=3.379×107 lbfs/ft2×5×1050.00234 slugs/ft3×V=80.342V        (I)

Use the spread sheet and equation (I), calculate the length of minivan for various speed range from 10 to 90 mph.

V1(mph)V1(ft/s)L(ft)
1014.66675.477851
2029.33342.738926
3044.00011.82595
4058.66681.369463
5073.33351.09557
6088.00020.912975
70102.66690.78255
80117.33360.684731
90132.00030.60865

Use the above table values; plot the length of the laminar boundary layer as a function of minivan speed as shown in the figure below:

Fox and McDonald's Introduction to Fluid Mechanics, Chapter 9, Problem 1P

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
Show that the pressure on the wing surface is increasing with downstream distance. Is this consistent with your calculations showing that the boundary layer is approaching separation? Explain your reasoning.
The viscous laminar flow of air over a flat plate results in the formation of a boundary layer. The boundary layer thickness at the end of the plate of length L is Delta L . When the plate length is increased to twice its original length. The percentage change in laminar boundary layer thickness at the end of the plate (with respect to Delta L ) is ______
The boundary layer formed as turbulent around the sphere is when ReD = 2.5*10^5 (a) Golf ball(D=43mm)  (b)Soccer ball(D=222mm) How fast does the ball have to be in order for a turbulent boundary layer to form around a ball? Assume standard atmospheric pressure.

Chapter 9 Solutions

Fox and McDonald's Introduction to Fluid Mechanics

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...
Knowledge Booster
Mechanical Engineering
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
    • SEE MORE QUESTIONS
    Recommended textbooks for you
  • Principles of Heat Transfer (Activate Learning wi...
    Mechanical Engineering
    ISBN:9781305387102
    Author:Kreith, Frank; Manglik, Raj M.
    Publisher:Cengage Learning
  • Principles of Heat Transfer (Activate Learning wi...
    Mechanical Engineering
    ISBN:9781305387102
    Author:Kreith, Frank; Manglik, Raj M.
    Publisher:Cengage Learning
    Heat Transfer – Conduction, Convection and Radiation; Author: NG Science;https://www.youtube.com/watch?v=Me60Ti0E_rY;License: Standard youtube license