Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470917855
Author: Bergman, Theodore L./
Publisher: John Wiley & Sons Inc
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Chapter 7, Problem 7.104P
To determine
To Discuss: The features associated with the 3 methods that are important for the selection of the application of cooling of the plastic part.
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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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- 8.21 WP In the final stages of production, a pharmaceutical is sterilized by heating it from 25 to 75°C as it moves at o.2 m/s through a straight thin- walled stainless steel tube of 12.7-mm diameter. A uniform heat flux is maintained by an electric resistance heater wrapped around the outer surface of the tube. If the tube is 10 m long, what is the required heat flux? If fluid enters the tube with a fully developed velocity profile and a uniform temperature profile, what is the surface temperature at the tube exit and at a distance of o.5 m from the entrance? Fluid properties may be approximated as p = 1000 kg/m³, c, = 4000 J/kg · K, µ = 2 × 10-3 kg/s · m, k = 0.8 W/m · K, and Pr = 10.arrow_forwardIMPROVEMENT WITH RADIATION SHIELD. A shield having an emissivity of 0.1 Example 8.13 is placed around the thermometer in Example 8.12 such that the area ratio A/A, is 0.3. The temperature indicated by the thermometer under these conditions is 5°C. The convection heat- transfer coefficient is assumed to be the same, and the shield may be assumed essentially to surround the thermometer. Calculate the true air temperature under these circumstances. And estimate its uncertainty E, = 0.1, A = 0.3, A, € = 0.9, h = 10 W/m2 - °C T, = 273 +5 = 278 K, T, = 263 Karrow_forwardA fuel rod of a PWR consists of about 320 solid fuel pellets inside a zircaloy cladding. Use the specified data to plot the distribution of temperature in the fuel rod. The temperature distribution should include the fuel region, the gap region, the cladding region, and end at the bulk coolant for two cases of low and high lin- ear heat generation rates. Data: DFuel = 0.96 cm, Dinside Clad = 0.985 cm, Doutside Clad = 1.12 cm, kFuel = 1.73 W/m C, kclad = 5.2 W/m-C, Twater = 300 C, ģ1ow = 5 kW/ft %3D (164 W/cm), and d'High = 15 kW/ft (492 W/cm). The heat transfer coefficient from the fuel rod to bulk coolant is 34 kW/m².C. The heat transfer coefficient in the gap region is 5.7 kW/m2.C for the low and is 11.4 kW/m2-C for the high linear heat generation rate.arrow_forward
- A fuel rod of a PWR consists of about 320 solid fuel pellets inside a zircaloy cladding. Use the specified data to plot the distribution of temperature in the fuel rod. The temperature distribution should include the fuel region, the gap region, the cladding region, and end at the bulk coolant for two cases of low and high lin- ear heat generation rates. Data: DFuel = 0.96 cm, Dinside Clad = 0.985 cm, Doutside Clad = 1.12 cm, kFuel = 1.73 W/m C, kClad = 5.2 W/m-C, TWater = 300 C, ģLow = 5 kW/ft %3D %3D (164 W/cm), and d'High = 15 kW/ft (492 W/em). The heat transfer coefficient %3D from the fuel rod to bulk coolant is 34 kW/m²-C. The heat transfer coefficient in the gap region is 5.7 kW/m-C for the low and is 11.4 kW/m².C for the high linear heat generation rate.arrow_forwardA fuel rod of a PWR consists of about 320 solid fuel pellets inside a zircaloy cladding. Use the specified data to plot the distribution of temperature in the fuel rod. The temperature distribution should include the fuel region, the gap region, the cladding region, and end at the bulk coolant for two cases of low and high lin- ear heat generation rates. Data: Druel = 0.96 cm, Dinside Clad = 0.985 cm, Doutside Clad = 1.12 cm, kfuel = 1.73 W/m C, kclad = 5.2 W/m C, Twater = 300 C, Low = 5 kW/ft (164 W/cm), and d'High = 15 kW/ft (492 W/cm). The heat transfer coefficient from the fuel rod to bulk coolant is 34 kW/m².C. The heat transfer coefficient in the gap region is 5.7 kW/m2.C for the low and is 11.4 kW/m.C for the high linear heat generation rate.arrow_forwardA fuel rod of a PWR consists of about 320 solid fuel pellets inside a zircaloy cladding. Use the specified data to plot the distribution of temperature in the fuel rod. The temperature distribution should include the fuel region, the gap region, the cladding region, and end at the bulk coolant for two cases of low and high lin- ear heat generation rates. Data: Druel = 0.96 cm, Dinside Clad = 0.985 cm, Doutside Clad = 1.12 cm, kfnel = 1.73 W/m C, kclad = 5.2 W/m C, Twater = 300 C, 41ow = 5 kW/ft (164 W/cm), and d'High = 15 kW/ft (492 W/cm). The heat transfer coefficient %3D from the fuel rod to bulk coolant is 34 kW/m.C. The heat transfer coefficient in the gap region is 5.7 kW/m.C for the low and is 11.4 kW/mC for the high linear heat generation rate.arrow_forward
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