Fluid Mechanics
8th Edition
ISBN: 9780073398273
Author: Frank M. White
Publisher: McGraw-Hill Education
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Chapter 1, Problem 1.59P
A solid cylinder of diameter D, length L, and density
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The laminar flow of a fluid with viscosity µ and density ρ in a circular pipe of radius R has a velocity distribution described by where UCL is the velocity on the centerline where r = 0. (a) Using a control volume analysis, find τw, the shear stress at the wall, in terms of R and the pressure gradient dp/dx. (b) Using the expression for the velocity profile, find τw, the shear stress at the wall, in terms of µ, R, and UCL. (c) Find the average velocity in terms of UCL. (d) Using the results from parts (a)-(c), show that where Re is the Reynolds number based on the diameter D.
A cylinder of mass m slides down from rest in a vertical tube whose inner surface is covered by a viscous oil of film thickness h. If the diameter and height of the cylinder are D and L, respectively, derive an expression for the velocity of the cylinder as a function of time, t. Discuss what will happen as t → ∞. Can this device serve as a viscometer?
Oil Coating: A long, continuous belt is pulled upwards through a chemical oil bath at velocity V0. The belt has rectangular cross-section and has length (L), width into the paper (W). The belt picks up a film of oil of thickness h, density ρ, and dynamic viscosity μ. Gravity g tends to make the oil drain down, but the movement of the belt keeps the fluid from running off completely. Assume fully developed, steady, laminar, incompressible and two-dimensional flow of oil to answer the following questions. Assume that no pressure gradient is needed in the vertical direction to drive the film flow. Also assume that the shear stress at the air-oil interface is zero (free shear condition). Assume no-slip condition for the fluid in contact with the moving belt. Justify any other assumptions you may make. Show all steps.
(a) Derive an expression for the two-dimensional velocity field inside the oil film in terms of the known parameters. Clearly indicate your co-ordinates and origin. You must…
Chapter 1 Solutions
Fluid Mechanics
Ch. 1 - Prob. 1.1PCh. 1 - Table A.6 lists the density of the standard...Ch. 1 - For the triangular element in Fig, P1.3,show that...Ch. 1 - Sand, and other granular materials, appear to...Ch. 1 - The mean free path of a gas, l, is defined as the...Ch. 1 - Henri Darcy, a French engineer, proposed that the...Ch. 1 - Convert the following inappropriate quantities...Ch. 1 - Suppose we know little about the strength of...Ch. 1 - A hemispherical container, 26 inches in diameter,...Ch. 1 - The Stokes-Oseen formula [33] for drag force F on...
Ch. 1 - P1.11 In English Engineering units, the specific...Ch. 1 - For low-speed (laminar) steady flow through a...Ch. 1 - The efficiency ? of a pump is defined as the...Ch. 1 - Figure P1.14 shows the flow of water over a dam....Ch. 1 - The height H that fluid rises in a liquid...Ch. 1 - Algebraic equations such as Bernoulli's relation,...Ch. 1 - The Hazen-Williams hydraulics formula for volume...Ch. 1 - For small particles at low velocities, the first...Ch. 1 - In his study of the circular hydraulic jump formed...Ch. 1 - Books on porous media and atomization claim that...Ch. 1 - Aeronautical engineers measure the pitching moment...Ch. 1 - Prob. 1.22PCh. 1 - During World War II, Sir Geoffrey Taylor, a...Ch. 1 - Air, assumed to be an ideal gas with k = 1.40,...Ch. 1 - On a summer day in Narragansett, Rhode Island, the...Ch. 1 - When we in the United States say a car's tire is...Ch. 1 - Prob. 1.27PCh. 1 - Wet atmospheric air at 100 percent relative...Ch. 1 - Prob. 1.29PCh. 1 - P1.30 Repeat Prob. 1.29 if the tank is filled with...Ch. 1 - Prob. 1.31PCh. 1 - Prob. 1.32PCh. 1 - A tank contai as 9 kg of CO2at 20°C and 2.0 MPa....Ch. 1 - Consider steam at the following state near the...Ch. 1 - In Table A.4, most common gases (air, nitrogen,...Ch. 1 - Prob. 1.36PCh. 1 - A near-ideal gas has a molecular weight of 44 and...Ch. 1 - In Fig. 1.7, if the fluid is glycerin at 20°C and...Ch. 1 - Prob. 1.39PCh. 1 - Glycerin at 20°C fills the space between a hollow...Ch. 1 - An aluminum cylinder weighing 30 N, 6 cm in...Ch. 1 - Prob. 1.42PCh. 1 - Prob. 1.43PCh. 1 - One type of viscometer is simply a long capillary...Ch. 1 - A block of weight W slides down an inclined plane...Ch. 1 - A simple and popular model for two nonnewtonian...Ch. 1 - Data for the apparent viscosity of average human...Ch. 1 - A thin plate is separated from two fixed plates by...Ch. 1 - An amazing number of commercial and laboratory...Ch. 1 - Prob. 1.50PCh. 1 - Prob. 1.51PCh. 1 - The belt in Fig. P1.52 moves at a steady velocity...Ch. 1 - A solid tune of angle 2 , base r0, and density...Ch. 1 - A disk of radius R rotates at an angular velocity ...Ch. 1 - A block of weight W is being pulled over a table...Ch. 1 - The device in Fig. P1.56 is called a cone-plate...Ch. 1 - Extend the steady flow between a fixed lower plate...Ch. 1 - The laminar pipe flow example of Prob. 1.12 can be...Ch. 1 - A solid cylinder of diameter D, length L, and...Ch. 1 - Prob. 1.60PCh. 1 - Prob. 1.61PCh. 1 - P1.62 The hydrogen bubbles that produced the...Ch. 1 - Derive Eq. (1.33) by making a force balance on the...Ch. 1 - Pressure in a water container can be measured by...Ch. 1 - The system in Fig. P1.65 is used to calculate the...Ch. 1 - Prob. 1.66PCh. 1 - Prob. 1.67PCh. 1 - Prob. 1.68PCh. 1 - A solid cylindrical needle of diameter d, length...Ch. 1 - Derive an expression for the capillary height...Ch. 1 - A soap bubble of diameter D1coalesces with another...Ch. 1 - Early mountaineers boiled water to estimate their...Ch. 1 - A small submersible moves al velocity V, in fresh...Ch. 1 - Oil, with a vapor pressure of 20 kPa, is delivered...Ch. 1 - An airplane flies at 555 mi/h. At what altitude in...Ch. 1 - Prob. 1.76PCh. 1 - Prob. 1.77PCh. 1 - P1.78 Sir Isaac Newton measured the speed of sound...Ch. 1 - Prob. 1.79PCh. 1 - Prob. 1.80PCh. 1 - Use Eq. (1.39) to find and sketch the streamlines...Ch. 1 - P1.82 A velocity field is given by u = V cos, v =...Ch. 1 - Prob. 1.83PCh. 1 - In the early 1900s, the British chemist Sir Cyril...Ch. 1 - Prob. 1.85PCh. 1 - A right circular cylinder volume v is to be...Ch. 1 - The absolute viscosity of a fluid is primarily a...Ch. 1 - Prob. 1.2FEEPCh. 1 - Helium has a molecular weight of 4.003. What is...Ch. 1 - An oil has a kinematic viscosity of 1.25 E-4 m2/s...Ch. 1 - Prob. 1.5FEEPCh. 1 - Prob. 1.6FEEPCh. 1 - FE1.7 Two parallel plates, one moving at 4 m/s...Ch. 1 - Prob. 1.8FEEPCh. 1 - A certain water flow at 20°C has a critical...Ch. 1 - Prob. 1.10FEEPCh. 1 - Sometimes we can develop equations and solve...Ch. 1 - When a person ice skates, the surface of the ice...Ch. 1 - Two thin flat plates, tilted at an angle a, are...Ch. 1 - Oil of viscosity and density drains steadily...Ch. 1 - Prob. 1.5CPCh. 1 - Prob. 1.6CPCh. 1 - Prob. 1.7CPCh. 1 -
C1.8 A mechanical device that uses the rotating...Ch. 1 - Prob. 1.9CPCh. 1 - A popular gravity-driven instrument is the...Ch. 1 - Mott [Ref. 49, p. 38] discusses a simple...Ch. 1 - A solid aluminum disk (SG = 2.7) is 2 in in...
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