Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
8th Edition
ISBN: 9781305387102
Author: Kreith, Frank; Manglik, Raj M.
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 5, Problem 5.3P
Evaluate the Nusselt number for flow over a sphere for the following conditions:
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
The velocity profile for laminar flow between two plates, as in Fig.3, is
2umaxy(h-y)
h4
u=
If the wall temperature is Tw at both walls, use the incompressible flow energy equation to solve for
the temperature distribution T (y) between the walls for steady flow.
Energy equation:
dT
pcp dt
y=h
y=0
•= kV²T +4
u(y)
v=W=0
Tw
T(y)
Fig.3. Fluid flow between two walls
Hello sir Muttalibi is a step
solution in detailing
mathematics the same as an
existing step solution
EXAMPLE 6-1
Momentum-Flux Correction Factor
for Laminar Pipe Flow
CV
Vavg
Consider laminar flow through a very long straight section of round pipe. It
is shown in Chap. 8 that the velocity profile through a cross-sectional area of
the pipe is parabolic (Fig. 6-15), with the axial velocity component given by
r4
V
R
V = 2V
1
avg
R2
(1)
where R is the radius of the inner wall of the pipe and Vavg is the average
velocity. Calculate the momentum-flux correction factor through a cross sec-
tion of the pipe for the case in which the pipe flow represents an outlet of
the control volume, as sketched in Fig. 6-15.
Assumptions 1 The flow is incompressible and steady. 2 The control volume
slices through the pipe normal to the pipe axis, as sketched in Fig. 6-15.
Analysis We substitute the given velocity profile for V in Eq. 6-24 and inte-
grate, noting that dA, = 2ar dr,
FIGURE 6–15
%3D
Velocity…
A capillary tube has an 8mm inside diameter through which liquid fluorine refrigerant R-11 flows at a rate of 0.03 cm3/s. The tube isto be used as a throttling device in an air conditioning unit. A model of this flow is constructed by using a pipe of 3cm inside diameter and water as the fluid medium. (Density of R-11 = 1.494 g/cm3 and its viscosity is 4.2 x10-4 Pa.s; Density of water is 1g/cm3 and its viscosity 8.9 x10-4 Pa.s)a) What is the required velocity in the model for dynamic similarity? Hint: For flow through a tube the Ne number can be expressed in terms of the Reynolds numberb) When dynamic similarity is achieved the pressure drop is measured at 50 Pa. What is the corresponding pressure drop in the capillary tube?Hint: In this case the Euler number defines dynamic similarity with reference to the static pressure drop
Chapter 5 Solutions
Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
Ch. 5 - Evaluate the Reynolds number for flow over a tube...Ch. 5 - 5.2 Evaluate the Prandtl number from the following...Ch. 5 - Evaluate the Nusselt number for flow over a sphere...Ch. 5 - 5.4 Evaluate the Stanton number for flow over a...Ch. 5 - Evaluate the dimensionless groups hcD/k,UD/, and...Ch. 5 - 5.6 A fluid flows at 5 over a wide, flat plate 15...Ch. 5 - 5.7 The average Reynolds number for air passing in...Ch. 5 - Prob. 5.8PCh. 5 - When a sphere falls freely through a homogeneous...Ch. 5 - 5.10 Experiments have been performed on the...
Ch. 5 - 5.13 The torque due to the frictional resistance...Ch. 5 - The drag on an airplane wing in flight is known to...Ch. 5 - 5.19 Suppose that the graph below shows measured...Ch. 5 - Engine oil at 100C flows over and parallel to a...Ch. 5 - For flow over a slightly curved isothermal...Ch. 5 - Air at 20C flows at 1 m/s between two parallel...Ch. 5 - Air at 1000C flows at an inlet velocity of 2 m/s...Ch. 5 -
5.43 A refrigeration truck is traveling at 130...Ch. 5 - The air-conditioning system in a Chevrolet van for...Ch. 5 - Determine the rate of heat loss from the wall of a...
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 a vertical wall at temperature T, is surrounded by a fluid at temperature T, a natural convection boundary layer flow will form. For laminar flow, the momentum equation is au ди. p(u-+ v) = PB(T – T)g + µ- ди ay to be solved, along with continuity and energy, for (u, v, T) with appropriate boundary conditions. The quantity B is the thermal expansion coefficient of the fluid. Use p, g, L, and (Tw- To) to nondimensionalize this equation. Note that there is no “stream" velocity in this type of flow.arrow_forwardA liquid of density 1150 kg/m3 flows steadily through a pipe of varying diameter and height. At Location 1 along the pipe, the flow speed is 9.47 m/s and the pipe diameter d1 is 11.7 cm. At Location 2, the pipe diameter d2 is 17.7 cm. At Location 1, the pipe is Ay=8.19 m higher than it is at Location 2. Ignoring viscosity, calculate the difference APbetween the fluid pressure at Location 2 and the fluid pressure at Location 1.arrow_forwardFor axial flow through a circular tube, the Reynolds numberfor the transition to turbulence is approximately 2300 based on the diameter and average velocity. Ifd= 5 cm and the fl uid is kerosene at 20 ° C, fi nd the volumeflow rate in m 3 /h that causes transition.arrow_forward
- A liquid with µ = 1.5x10-3 kgf.s / m2 flows over a horizontal wall. Calculate velocity gradient and shear stress at the limits and points located at 1, 2, 3 cm from its surface. Suppose a destruction of parabolic speed. THE parabola has its apex at point A and the origin of the axis system is at B.arrow_forwardConsider a potential flow describing a uniform flow around a cylinder. What is the force on the cylinder (per unit length of the cylinder) that comes from the upstream half of the cylinder? Answer it terms of the upstream velocity Uo, fluid density p, and cylinder radius a? You may take the upstream pressure po to be 0.arrow_forwardUnless otherwise stated, given: Properties of air, p = 1.18kg/m³, µ = 1.85 x 10-2mPa·s. Properties of water, p = 997kg/m³, µ = 0.89mPa · s. 1. Consider an annulus flow. Two long cylinders are concentrically aligned as shown in Figure Q1. A viscous fluid filled up the space in between. The inner cylinder ofradius R; is stationary while the outer cylinder of radius R, rotates with an angular velocity w. Neglect gravitational effect. (a) Simplify the momentum equations. State all assumptions. (b) Apply the boundary conditions and determine the velocity. (c) Plot velocity against r and sketch the velocity profile for R;arrow_forward338 B/s O 1: 56% E 3:01 Question: Gasoline is flowing through this 180° pipe bend. The pipe cross-sectional area is 18 in?. Take the pipe weight as 5 Kg. Flow rate is 0.5 liters/s. Pressure at section-1 6 psia, pressure at section-2 is 4 psia. Calculate the anchoring force required to hold this pipe and also show its direction, referenced to proper 2-dimensional a cartesian coordinate system. (2 1arrow_forwardConsider steady, incompressible, parallel, laminar flow of a viscous fluid falling between two infinite vertical walls. The distance between the walls is h, and gravity acts in the negative z-direction (downward in the figure). There is no applied (forced) pressure driving the flow—the fluid falls by gravity alone. The pressure is constant everywhere in the flow field. For the fluid falling between two parallel vertical walls, generate an expression for the volume flow rate per unit width (V·/L) as a function of ?, ? , h, and g. Compare your result to that of the same fluid falling along one vertical wall with a free surface replacing the second wall, all else being equal. Discuss the differences and provide a physical explanation.arrow_forwardA viscous incompressible Newtonian fluid is contained between two fixed parallel plates inclined at an angle 0, and the flow is driven by both constant pressure gradient E = constant) and gravity. The distance between the two plates is 2H and the chosen system of coordinates is shown in the figure. Assuming steady, 2D, and parallel flow (v = w = 0) and using differential analysis: (a) Show that the flow is fully developed using continuity equation; and (b) Find the velocity profile u(y) in terms of ,H,P,g,0,H de using Navier-Stokes equations with appropriate boundary conditions. 211arrow_forwardA potential flow model of flow over a circular cylinder is described by the following velocity potential R² $ = U_cms (0) (r + 47) Find the magnitude of the pressure gradient normal to the cylinder surface, at an angle of 30° from the leading edge. The constants are given as U = 8 m/s and R = 2 m, while the density of the fluid is p = 1000 kg m-³. Give your answer in Pa/m to the nearest integer value.arrow_forwardAir at 20 °C flows over a flat aluminum plate at 30 m/s to cool electrical components on the other side. The plate measures 80 cm square. The plate is to be kept below a constant temperature of 80 °C, but as it is a conductive metal, we can assume the plate has a constant temperature. Plot h along the plate, Find the average h for the whole plate and, Tell me Q, the total heat dissipated when the plate is at its maximum temperature.arrow_forward(b) In two dimensional boundary layer, shear stress was changed linearly from the solid surface toward y-axis until it reach the value of zero at y = 6. Based on Table 2 and setting given to you; () Derive the equation of displacement thickness and momentum thickness using Von Karman Approximation Method ; and (ii) Determine the accuracy of this method in determining the value of displacement thickness and momentum thickness. Table 2 : Equation of Velocity Profile Setting Equation wU = 3(y/8)/2 – (y/8j?/2arrow_forwardarrow_back_iosSEE MORE QUESTIONSarrow_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