Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470917855
Author: Bergman, Theodore L./
Publisher: John Wiley & Sons Inc
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 7, Problem 7.47P
A circular pipe of 25-mm outside diameter is placed in an airstream at
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Air at 295 K flows at 3 m/s over a flat plate at 390 K. The air properties are as follows: density =1.1 kg/m3, viscosity =18.1×10−6 Pa.s, specific heat capacity =1005 J/kgK, and thermal conductivity =0.024 W/mK. The velocity and temperature profiles are assumed to be linear, giving the local Nusselt number to be Nux = 0.289 Rex1/ 2Pr1/3. The flow will become turbulent at a Reynolds number of 5×105. Assume the width of the plate perpendicular to the air flow is 1 m.
At what distance from the leading edge does the flow become turbulent? ________m
What is the heat transfer at the point of transition? ___________W
What is the total heat transfer along the length of the plate where the flow is laminar? __________W
Air at 22˚C and at atmospheric pressure flows over a flat plate at a velocity of 1.65 m/s. If the length
of the plate is 2.179 m and its temperature is 98 ˚C, Calculate Heat rate by using exact and approximate
methods both. What is the %age difference of the heat transfer rate values by these methods? Take
width of the plate as unity.
Properties given at 60˚C are as follows:
Density: 1.058 kg/m3
, cp = 1.005 kJ/kg˚C, k= 0.02897 w/m˚C, Kinematic viscosity is 18.97 × 10-6 m2
/s
A 0.5-m diameter uninsulated pipe transports high-temperature steam. Its surface temperature is 150°C
and it is exposed to air at -10°C. The air moves in cross flow over the pipe with a velocity of 5 m/s. To
compute for the Nusselt number of the air flow, what is the exact value of the temperature in °C on
which the air properties should be based?
Chapter 7 Solutions
Fundamentals of Heat and Mass Transfer
Ch. 7 - Consider the following fluids at a film...Ch. 7 - Engine oil at 100C and a velocity of 0.1 m/s flows...Ch. 7 - Consider steady, parallel flow of atmospheric air...Ch. 7 - Consider a liquid metal (Pr1), with free stream...Ch. 7 - Consider the velocity boundary layer profile for...Ch. 7 - Consider a steady, turbulent boundary layer on and...Ch. 7 - Consider flow over a flat plate for which it is...Ch. 7 - A flat plate of width 1 m is maintained at a...Ch. 7 - An electric air heater consists of a horizontal...Ch. 7 - Consider atmospheric air at 25C and a velocity of...
Ch. 7 - Repeat Problem 7.11 for the case when the boundary...Ch. 7 - Consider water at 27°C in parallel flow over an...Ch. 7 - Explain under what conditions the total rate of...Ch. 7 - In fuel cell stacks, it is desirable to operate...Ch. 7 - The roof of a refrigerated truck compartment is of...Ch. 7 - The top surface of a heated compartment consists...Ch. 7 - Calculate the value of the average heat transfer...Ch. 7 - The proposed design for an anemometer to determine...Ch. 7 - Steel (AISI 1010) plates of thickness =6mm and...Ch. 7 - Consider a rectangular fin that is used to cool a...Ch. 7 - The Weather Channel reports that it is a hot,...Ch. 7 - In the production of sheet metals or plastics, it...Ch. 7 - An array of electronic chips is mounted within a...Ch. 7 - A steel strip emerges from the hot roll section of...Ch. 7 - In Problem 7.23. an anemometer design was...Ch. 7 - One hundred electrical components, each...Ch. 7 - The boundary layer associated with parallel flow...Ch. 7 - Forced air at 250C and 10 m/s is used to cool...Ch. 7 - Air at atmospheric pressure and a temperature of...Ch. 7 - Consider a thin, 50mm50mm fuel cell similar to...Ch. 7 - The cover plate of a flat-plate solar collector is...Ch. 7 - An array of 10 silicon chips, each of length...Ch. 7 - A square (10mm10mm) silicon chip is insulated on...Ch. 7 - A circular pipe of 25-mm outside diameter is...Ch. 7 - An L=1-m- long vertical copper tube of inner...Ch. 7 - A long, cylindrical, electrical heating element of...Ch. 7 - Consider the conditions of Problem 7.49, but now...Ch. 7 - Pin fins are to be specified for use in an...Ch. 7 - Prob. 7.52PCh. 7 - Prob. 7.53PCh. 7 - Hot water at 500C is routed from one building in...Ch. 7 - In a manufacturing process, long aluminum rods of...Ch. 7 - Prob. 7.58PCh. 7 - To determine air velocity changes, it is proposed...Ch. 7 - Determine the convection heat loss from both the...Ch. 7 - Prob. 7.63PCh. 7 - Prob. 7.64PCh. 7 - Prob. 7.67PCh. 7 - A thermocouple is inserted into a hot air duct to...Ch. 7 - Consider a sphere with a diameter of 20 mm and a...Ch. 7 - Prob. 7.76PCh. 7 - A spherical, underwater instrument pod used to...Ch. 7 - Worldwide. over a billion solder balls must be...Ch. 7 - Prob. 7.80PCh. 7 - Prob. 7.81PCh. 7 - Consider the plasma spray coating process of...Ch. 7 - Prob. 7.83PCh. 7 - Tissue engineering involves the development of...Ch. 7 - Consider temperature measurement in a gas stream...Ch. 7 - Prob. 7.89PCh. 7 - A preheater involves the use of condensing steam...Ch. 7 - Prob. 7.91PCh. 7 - A tube bank uses an aligned arrangement of...Ch. 7 - A tube bank uses an aligned arrangement of...Ch. 7 - Repeat Problem 7.94, but with NL=7,NT=10, and...Ch. 7 - Heating and cooling with miniature impinging jets...Ch. 7 - A circular transistor of 10-mm diameter is cooled...Ch. 7 - A long rectangular plate of AISI 304 stainless...Ch. 7 - A cryogenic probe is used to treat cancerous skin...Ch. 7 - Prob. 7.103PCh. 7 - Prob. 7.104PCh. 7 - Prob. 7.105PCh. 7 - Consider the packed bed of aluminum spheres...Ch. 7 - Prob. 7.108PCh. 7 - Prob. 7.109PCh. 7 - Prob. 7.111PCh. 7 - Packed beds of spherical panicles can be sintered...Ch. 7 - Prob. 7.114PCh. 7 - Prob. 7.116PCh. 7 - Prob. 7.117PCh. 7 - Prob. 7.118PCh. 7 - Prob. 7.119PCh. 7 - Prob. 7.120PCh. 7 - Dry air at 35°C and a velocity of 20 m/s flows...Ch. 7 - Prob. 7.123PCh. 7 - Benzene, a known carcinogen, has been spilled on...Ch. 7 - Prob. 7.125PCh. 7 - Prob. 7.126PCh. 7 - Condenser cooling water for a power plant is...Ch. 7 - Prob. 7.128PCh. 7 - In a paper-drying process, the paper moves on a...Ch. 7 - Prob. 7.131PCh. 7 - Prob. 7.132PCh. 7 - Prob. 7.133PCh. 7 - Prob. 7.134PCh. 7 - Prob. 7.136PCh. 7 - It has been suggested that heat transfer from a...Ch. 7 - Prob. 7.138PCh. 7 - Cylindrical dry-bulb and wet-bulb thermometers are...Ch. 7 - The thermal pollution problem is associated with...Ch. 7 - Cranberries are harvested by flooding the bogs in...Ch. 7 - A spherical drop of water, 0.5 mm in diameter, is...Ch. 7 - Prob. 7.143PCh. 7 - Prob. 7.144PCh. 7 - Prob. 7.145PCh. 7 - Prob. 7.146PCh. 7 - Prob. 7.147PCh. 7 - Consider an air-conditioning system composed of a...Ch. 7 - Prob. 7.149P
Additional Engineering Textbook Solutions
Find more solutions based on key concepts
The cylinder volume below the constant loaded piston has two compartments, A and B, filled with water, as shown...
Fundamentals Of Thermodynamics
The expression for the rate at which useful heat is collected per unit area of the collector and also find the ...
Introduction to Heat Transfer
Using Fig. 4-1, draw a conclusion about the comfort of a mixed group of men and women in typical seasonal cloth...
Heating Ventilating and Air Conditioning: Analysis and Design
If it is subjected to the force system shown, determine the stress components that act at point A, and show the...
Mechanics of Materials (10th Edition)
For the case of plane stress, show that Hookes law can be written as x=E(1v2)(x+vy),y=E(1v2)(y+vx)
Mechanics of Materials
Convert a distance of 1.36 miles to meters.
Applied Fluid Mechanics (7th Edition)
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
- The outer diameter of a pipe is 25 mm and its surface temperature is 90 ° C. Air at a temperature of 30 ° C flows diagonally over the pipe at 15 m / s. What is the resistance force per unit length of the pipe? What is the heat transfer from the unit length of the pipe?arrow_forwardCalculate the heat transfer (in Watts) in the first 20 cm of the plate assuming unit depth, if the plate is heated to a temperature of 100C over it complete length with air flowing over it at a temperature of 27°C. [Properties of air at 63.5°C are: k = 0.02749 W/mK, v = 17.36 x 10“ m/s, Cp = 1.006 kJ/kg K and Pr= 0.7.]arrow_forwardAir at 20 C is flowing over a flat plate ( 6m long and 1.5m wide). The plate is maintained at 140 C. Find the heat loss from the plate if the air is flowing parallel to 6m side with a velocity of 2 m/s. What is the percentage change in heat transfer if the air flow is parallel to 1.5m side. The properties of air are: p=1.06 kg/m v 2.548x10 m/s, k=0.0295 W/mK and Pr-0.7. Nu =0.664Res Pr1 for laminar flow Nu, = (0.037RE-871)Pr for turbulent flowarrow_forward
- Air stream at 27 degrees * C is moving at 0.3 m/s across a 100 W electric bulb at 127 degrees * C. If the bulb is approximated by a 60 mm diameter sphere, estimate the heat transfer rate and the percentage of power lost due to convection.arrow_forwardI need correctlyarrow_forwardConsider two cases involving parallel flow of dry air at V = 1.5 m/s, T=45°C, and atmospheric pressure over an isothermal plate at T = 20°C. In the first case, Rex, = 5 x 105, while in the second case the flow is tripped to a turbulent state at x = 0 m. At what x -location, in m, are the thermal boundary layer thicknesses of the two cases equal? What are the local heat fluxes, in W/m², at this location for the two cases? x = 9jam 9 turb II = i i m W/m² W/m²arrow_forward
- Consider two cases involving parallel flow of dry air at V = 3.5 m/s, T = 45°C, and atmospheric pressure over an isothermal plate at T = 20°C. In the first case, Rex.c = 5 × 105, while in the second case the flow is tripped to a turbulent state at x = 0m. At what x -location, in m, are the thermal boundary layer thicknesses of the two cases equal? What are the local heat fluxes, in W/m², at this location for the two cases? x = 9'1'am 9 turb = = i i i m W/m² W/m²arrow_forward1-The wind blows with velocity 0.4 m/s parallel to the both sides of a flat plate with rectangular area 10m×10 m. The plate temperature is T0=60◦C, and the temperature of the air free stream is 20◦C. Assume laminar flow and calculate: (a) maximum boundary layer thickness, (b) the total force experienced by the plate, (c) estimate the total heat transfer rate by laminar forced convection (d) Make a qualitative sketch of how the local heat flux qx and τx varies along the length L.arrow_forwardA vertical pipe 90 mm diameter and 2.5 m height is maintained at a constant temperature of 125 o The pipe is surrounded by still atmospheric air at 25 oC. Find heat loss by natural convection. Properties of water at 75 oC: Density = 1.0145 kg/m3 Kinematic viscosity = 20.55 x10-6 m2/s Prandtl number (Pr) = 0.693 Thermal conductivity (k) = 30.06 x 10–3 W/m Karrow_forward
- Air with free stream temperature of 10 C is flowing over a flat plate (1.5m long and Im wide). The air is flowing along 1.5m side of the plate. The plate is maintained at 90 C. Find the velocity of air required to have a rate of heat dissipation as 3.75 kW. Use the correlations: Nu =0.664Res Pro3 for laminar flow Nu, = (0.037R *-871)Pr for turbulent flow Take the properties p = 1.0877 kg/m u=2.029x10 m/s, k=0.028 W/mK, C,-1.007KJ/kg.K and Pr=0.703 %3Darrow_forwardA vehicle carrying refrigeration box is moving with a speed of 24 m/s on a road withambient temperature of 323 K. The dimensions of box are 3 m(H) × 4 m (W) × 10 m (L).Assume a wall temperature of 283 K and air flow is parallel to the longest side of the box.Neglecting the heat loss from the front side and backside of the box, calculate heat lossfrom four surfaces. For flow over flat surfaces useNu = 0.036(Re)0.8(Pr)1/3The properties of air at bulk mean temperature are : = 1.165 kg/m3, Pr = 0.701, cp = 1005 J/kg – K, = 16 × 10–6m2/sarrow_forwardAir at 20 °C flows with a velocity 10 m/s along a 4 m flat plate which is maintained at uniform temperature of 100 °C. What is the local heat flux at haft distance from the leading edge of the plate (at middle of the plate)? For air: k = 0.025 W/mK, v= 20x10-6 m2/s, Pr = 0.7arrow_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
Intro to Compressible Flows — Lesson 1; Author: Ansys Learning;https://www.youtube.com/watch?v=OgR6j8TzA5Y;License: Standard Youtube License