Fluid Mechanics: Fundamentals and Applications
4th Edition
ISBN: 9781259696534
Author: Yunus A. Cengel Dr., John M. Cimbala
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Videos
Question
Chapter 11, Problem 123P
To determine
The average friction coefficient over the entire plate.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Air flow at a constant speed (Ug = 10 m/s) is forming a two-dimensional incompressible
laminar boundary layer along a flat plate The velocity profile inside the boundary layer is
given by:
-2²-²
a) Determine the shear stress at the wall, at y = 3 mm and y = 10 mm.
b) Calculate the boundary layer displacement thickness.
c) Calculate the mass flow rate through the boundary layer per unit width.
Q2)
In flow over a surface, velocity and temperature profiles are of the forms
u(y) = Ay + By² + Cy3
and
T(y) = D+ Ey + Fy? - Gy3
where the coefficients A through G are constants. Obtain expressions for the friction
coefficient C, and the convection coefficient h in terms of uo, To, and appropriate profile
coefficients and fluid properties.
Q3)
Water at a temperature of T = 25°C flows over one of the surfaces of a steel wall
(AISI 1010) whose temperature is Ts1 = 40°C. The wall is 0.35 m thick, and its other surface
temperature is Ts,2
= 100°C. For steady state conditions what is the convection coefficient
associated with the water flow? What is the temperature gradient in the wall and in the water
that is in contact with the wall? Sketch the temperature distribution in the wall and in the
adjoining water.
-1/5
A// For laminar flow over a flat plate, the local heat transfer coefficient h, is known to
vary as x¹/5, where x is the distance from the leading edge (x =0) of the plate. What is
the ratio of the average coefficient between the leading edge and some location x on
the plate to the local coefficient at x? for velocity equation u= 2-0.43x+x² Plot the local
heat transfer coefficient over a 0.8 cm length(take T-35c)
B// Air at 1 atm and 15°C flows through a long rectangular duct 7.5 cm by 15 cm. A
1.8-m section of the duct is maintained at 120°C, and the average air temperature at
exit from this section is 65°C. Calculate the airflow rate and the total heat transfer
Chapter 11 Solutions
Fluid Mechanics: Fundamentals and Applications
Ch. 11 - What is drag? What causes it? Why do we usually...Ch. 11 - Prob. 2CPCh. 11 - Which bicyclist is more likely to go faster: one...Ch. 11 - Prob. 4CPCh. 11 - Define the frontal area of a body subjected to...Ch. 11 - Define the planform area of a body subjected to...Ch. 11 - Prob. 7CPCh. 11 - What is the difference between streamlined and...Ch. 11 - Prob. 9CPCh. 11 - During flow over a given body, the drag force, the...
Ch. 11 - During flow over a given slender body such as a...Ch. 11 - What is terminal velocity? How is it determined?Ch. 11 - What is the difference between skin friction drag...Ch. 11 - What is the effect of surface roughness on the...Ch. 11 - Prob. 15CPCh. 11 - What is flow separation? What causes it? What is...Ch. 11 - Prob. 17CPCh. 11 - Consider laminar flow over a flat plate. How does...Ch. 11 - In general, how does the drag coefficient vary...Ch. 11 - Fairings are attached to the front and back of a...Ch. 11 - Prob. 21PCh. 11 - The resultant of the pressure and wall shear...Ch. 11 - Prob. 23PCh. 11 - Prob. 24PCh. 11 - To reduce the drag coefficient and thus to improve...Ch. 11 - A circular sign has a diameter of 50 cm and is...Ch. 11 - Prob. 28PCh. 11 - Prob. 29PCh. 11 - At highway speeds, about half of the power...Ch. 11 - A submarine can be treated as an ellipsoid with a...Ch. 11 - A 70-kg bicyclist is riding her 1 5-kg bicycle...Ch. 11 - A wind turbine with two or four hollow...Ch. 11 - During steady motion of a vehicle on a level road,...Ch. 11 - Prob. 37EPCh. 11 - A 0.80-m-diameter, 1 .2-rn-high garbage can is...Ch. 11 - An 8-mm-diameter plastic sphere whose density is...Ch. 11 - Prob. 40PCh. 11 - The drag coefficient of a vehicle increases when...Ch. 11 - To reduce the drag coefficient and thus to improve...Ch. 11 - During major windstorms, high vehicles such as RVs...Ch. 11 - What does the friction coefficient represent in...Ch. 11 - What fluid property is responsible for the...Ch. 11 - How is the average friction coefficient determined...Ch. 11 - Prob. 47EPCh. 11 - The local atmospheric pressure in Denver, Colorado...Ch. 11 - Prob. 50PCh. 11 - Prob. 51EPCh. 11 - Air at 25C and 1 atm is flowing over a long flat...Ch. 11 - Prob. 54PCh. 11 - During a winter day, wind at 70 km/h, 5C , and I...Ch. 11 - Prob. 56PCh. 11 - The forming section of a plastics plant puts out a...Ch. 11 - Prob. 58CPCh. 11 - Why is flow separation in flow over cylinders...Ch. 11 - Prob. 60CPCh. 11 - A 5-mm-diameter electrical transmission line is...Ch. 11 - A 1ong 5-cm-diameter steam pipe passes through...Ch. 11 - Consider 0.8-cm-diameter hail that is falling...Ch. 11 - Prob. 64EPCh. 11 - Prob. 65PCh. 11 - Prob. 66PCh. 11 - Prob. 67EPCh. 11 - One of the popular demonstrations in science...Ch. 11 - Prob. 69PCh. 11 - What is stall? What causes an airfoil to stall?...Ch. 11 - Prob. 71CPCh. 11 - Air is flowing past a symmetrical airfoil at zero...Ch. 11 - Both the lift and the drag of an airfoil increase...Ch. 11 - Prob. 74CPCh. 11 - Prob. 75CPCh. 11 - Air is flowing past a symmetrical airfoil at an...Ch. 11 - Prob. 77CPCh. 11 - Prob. 78CPCh. 11 - Prob. 79CPCh. 11 - Prob. 80CPCh. 11 - How do flaps affect the lift and the drag of...Ch. 11 - Prob. 82EPCh. 11 - Consider an aircraft that takes off at 260 km/h...Ch. 11 - Prob. 84PCh. 11 - Prob. 85PCh. 11 - A tennis ball with a mass of 57 and a diameter of...Ch. 11 - A small aircraft has a wing area of 40 m2, a lift...Ch. 11 - Prob. 89PCh. 11 - Consider a light plane that has a total weight of...Ch. 11 - A small airplane has a total mass of 1800 kg and a...Ch. 11 - An airplane has a mass of 48.000 k. a wins area of...Ch. 11 - Prob. 93EPCh. 11 - Prob. 94PCh. 11 - Prob. 95EPCh. 11 - A 2-zn-high, 4-zn-wide rectangular advertisement...Ch. 11 - 11-97 A plastic boat whose bottom surface can be...Ch. 11 - Prob. 99PCh. 11 - Prob. 100EPCh. 11 - A commercial airplane has a total mass of 150.000...Ch. 11 - Prob. 102PCh. 11 - Prob. 103PCh. 11 - Prob. 104PCh. 11 - Prob. 105PCh. 11 - Prob. 107PCh. 11 - Prob. 108PCh. 11 - Prob. 109PCh. 11 - Prob. 110PCh. 11 - Prob. 111PCh. 11 - Prob. 113PCh. 11 - Prob. 115PCh. 11 - Prob. 116PCh. 11 - Prob. 117PCh. 11 - Prob. 118PCh. 11 - Prob. 119PCh. 11 - The region of flow trailing the body where the...Ch. 11 - Prob. 121PCh. 11 - Prob. 122PCh. 11 - Prob. 123PCh. 11 - Prob. 124PCh. 11 - Prob. 125PCh. 11 - Prob. 126PCh. 11 - An airplane has a total mass of 3.000kg and a wing...Ch. 11 - Prob. 128PCh. 11 - Write a report on the history of the reduction of...Ch. 11 - Write a report oil the flips used at the leading...Ch. 11 - Discuss how to calculate drag force a unsteady...Ch. 11 - Large commercial airplanes cruise at high...Ch. 11 - Many drivers turn off their air conditioners and...Ch. 11 - Consider the boundary layer growing on a flat...
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
- Engine oil at 100C flows over and parallel to a flat surface at a velocity of 3 m/s. Calculate the thickness of the hydrodynamic boundary layer at a distance 0.3 m from the leading edge of the surface.arrow_forwardTopic: Heat transfer Completely solve and box the final answer. A 20degC water flows to 50cmx60cm flat plate with velocity of 6m/s . The flat plate surface temperature is maintained at 40deg C. The air flows parallel to the 50cm side of the plate. If the kinematic viscosity of water is 78x10-8 m2/s, at what length the flow become turbulent? If the average laminar heat transfer coefficient of water is 7740W/m2 degC, what is the overall heat transfer at the laminar section?arrow_forward) A 75 mm-diameter orifice is on the verticalside of a closed tank. The tank rests on a flat groundand the orifice is 0.5 m above the ground. Filled withfour fluids with air on the topmost portion that is undera pressure of 15 KPa, and the rest of specific gravities of0.80, 1.0, and 1.50, respectively, the jet hits the groundat a horizontal distance of 3.75 m. If the liquids have thesame thickness, and the power lost in the system is 233watts, determine the following:(a) The initial discharge in L/s if C=0.63.(b) The thickness of each liquid in m.(c) The coefficient of contraction.arrow_forward
- For free flow of air over a plate, it is given that Grashof number is 7 x 10º and Prandtl number is 0.25 Then, determine the type of flow.arrow_forwardRequired information Air flowing dver a 1-m-long flat plate at a velocity of 7 m/s has a friction coefficient given as Cf=0.664(Vx/V)-0.5 is the location along the plate. P, where x Given: The properties of air at 20°C are u = 1.825 x 10-5 kg/ms, v = 1.516 x 10-5 m/s, and p= 1.204 kg/m. Determine the air velocity gradient on the plate surface. Evaluate the air properties at 20°C and 1 atm. (Round the final answer to two decimal places.) The air velocity gradient on the plate surface is s-1arrow_forwardA 20 °C water flows to 50cmx60cm flat plate with velocity of 6m/s . The flat plate surface temperature is maintained at 40 °C The water flows parallel to the 50cm side of the plate. If the kinematic viscosity of water is 78x10-8 m2/s, What is the local heat flux (Q/A) at the end of the plate (k=0.86 W/m deg C, Re=3840000, and Pr=0.7)?arrow_forward
- Briefly explain the shear stress and velocity profile for turbulent flow.arrow_forward-drill Pipe supp-rt its an oil wel is drilled, each nerw section the we'git Own weight of the pipe and 8.00-m-long steal Pipe that supports a 200,000g dril 5A and a 5 km length the drill bit beneath it. Calculate the stréch ing new and OF pipe with a linear mass dersity of 20 kglm. Treat the pipe as a solid cylinder with a 8.00 cm diaimeter.arrow_forwardTopic: Heat transfer Completely solve and box the final answer. 1. A 20degC water flows to 50cmx60cm flat plate with velocity of 5.2m/s . The flat plate surface temperature is maintained at 40deg C. The air flows parallel to the 50cm side of the plate. If the kinematic viscosity of water is 78x10-8 m2/s, at what length the flow become turbulent?arrow_forward
- Engine oil at 100°C flows on the top surface of a 1-m-long flat plate maintained at 20°C. The oil’s freestream speed (u infinity) is 0.1 m/s. Find the engine oil properties from the table A.5 A. Evaluate the Reynolds number, local convection coefficient, heat flux and shear stress at the end of the plate (x = L). Is the air flow laminar or turbulent over the plate?B. Evaluate the average convection coefficient, average heat flux, average shear stress and drag force over the plate.arrow_forwardYou are designing an IC heatsink which uses round pins in cross-flow. The heatsink must dissipate 3000W. The heatsink has 10 rows of 8 columns of round pins with a diameter of 1mm. The pins have longitudinal and transverse pitch of 6mm. The incoming air is at 25oC with a velocity of 3 m/s. Assume fluid properties are constant. If the pins are arranged in-line: a) Find the Reynold’s Number b) Find the Nusselt Number c) If the pins are 30mm tall, how hot must the pin surface be (average) to dissipate the proper amount of heat?arrow_forwardIn the laminar flow of air (Pr = 0.7) over a heated plate, if & and 8, denote, respectively, the hydrodynamic and thermal boundary layer thicknesses, then (a) 8 = 8, (c) 8 8- (d) 8 = 0 but 8,# 0arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author: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