Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470501979
Author: Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine
Publisher: Wiley, John & Sons, Incorporated
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Chapter 7, Problem 7.128P
To determine
The initial rate of heat transfer from the plate and also find the corresponding rate of change of the plate temperature.
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Air at 200C and at a pressure of 1 bar is flowing over a flat plate at a velocity of 3 m/s. If the plate is 280 mm wide and at 560C, calculate the following quantities at x = 280 mm given that properties of air at the bulk mean temperature 20 + 56/2= 380C are:
(i) Boundary layer thickness,(ii) Local friction coefficient,(iii) Average friction coefficient,(iv) Shearing stress due to friction(v) Thickness of the boundary layer,(vi) Local convective heat transfer coefficient,(vii) Average convective heat transfer coefficient,(viii) Rate of heat transfer by convection(ix) Total drag force on the plate, and(x) Total mass flow rate through the boundary
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1- the thickness of the hydrodynamic boundary layer at the end of the plate2- the thickness of the thermal boundary layer at the end of the plate3- the local and average heat transfer coefficient at the end of the plate4- the total heat flux transferred from the heated surface.
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
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