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
Concept explainers
Videos
Textbook Question
Chapter 2, Problem 2.2P
A small dam, which is idealized by a large slab 1.2 m thick, is to be completely poured in a short Period of time. The hydration of the concrete results in the equivalent of a distributed source of constant strength of 100 W/m3. If both dam surfaces are at 16°C, determine the maximum temperature to which the concrete will be subjected, assuming steady-state conditions. The thermal conductivity of the wet concrete can be taken as 0.84 W/m K.
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
. A small dam, which can be idealized by a large slab 1.2-m thick, is to be completely poured in a short period of time. The hydration of the concrete results in the equivalent of a distributed source of constant strength of 100 W/m3. If both dam surfaces are at 16°C, determine the maximum temperature to which the concrete will be subjected, assuming steady-state conditions. The thermal conductivity of the wet concrete can be taken as 0.84 W/m3. Suatu pelat datar dari besi dari seterika listrik berdaya 1200-
6. A cylindrical electric heater of outside diameter D = 2.5 cm and length L= 2 m is immersed
horizontally into a pool of mercury at 100°C. If the surface of the heater is maintained at an
average temperature of 300°C, calculate the rate of heat transfer to the mercury.
It is designed in such a way that the internal temperature of a commercial heat treatment furnace can reach up to 165 oC. All surfaces of the furnace consist of firebrick (10 cm), insulation material and sheet metal (3mm) from the inside out. Given that the outdoor temperature is 22 oC, the outer sheet will be allowed to go up to 35 oC, which is a temperature that will not be disturbed by hand contact. In this case, determine the insulation material thickness to be used. Insulation material thermal conductivity coefficient is 0.066 insulation W / m oC, 60 W / m oC for sheet metal and 115 W / m oC for firebrick. Indoor heat transfer coefficient will be accepted as 25 W / m2 oC and 12 W / m2 oC for outdoor environment.
Chapter 2 Solutions
Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
Ch. 2 - A plane wall, 7.5 cm thick, generates heat...Ch. 2 -
2.2 A small dam, which is idealized by a large...Ch. 2 - 2.3 The shield of a nuclear reactor is idealized...Ch. 2 - A plane wall 15 cm thick has a thermal...Ch. 2 - 2.5 Derive an expression for the temperature...Ch. 2 - A plane wall of thickness 2L has internal heat...Ch. 2 - 2.7 A very thin silicon chip is bonded to a 6-mm...Ch. 2 - 2.9 In a large chemical factory, hot gases at 2273...Ch. 2 - 2.14 Calculate the rate of heat loss per foot and...Ch. 2 - 2.15 Suppose that a pipe carrying a hot fluid with...
Ch. 2 - Prob. 2.16PCh. 2 - Estimate the rate of heat loss per unit length...Ch. 2 - The rate of heat flow per unit length q/L through...Ch. 2 - A 2.5-cm-OD, 2-cm-ID copper pipe carries liquid...Ch. 2 - A cylindrical liquid oxygen (LOX) tank has a...Ch. 2 - Show that the rate of heat conduction per unit...Ch. 2 - Derive an expression for the temperature...Ch. 2 - Heat is generated uniformly in the fuel rod of a...Ch. 2 - 2.29 In a cylindrical fuel rod of a nuclear...Ch. 2 - 2.30 An electrical heater capable of generating...Ch. 2 - A hollow sphere with inner and outer radii of R1...Ch. 2 - 2.34 Show that the temperature distribution in a...Ch. 2 -
2.38 The addition of aluminum fins has been...Ch. 2 - The tip of a soldering iron consists of a 0.6-cm-...Ch. 2 - One end of a 0.3-m-long steel rod is connected to...Ch. 2 - Both ends of a 0.6-cm copper U-shaped rod are...Ch. 2 - 2.42 A circumferential fin of rectangular cross...Ch. 2 - 2.43 A turbine blade 6.3 cm long, with...Ch. 2 - 2.44 To determine the thermal conductivity of a...Ch. 2 - 2.45 Heat is transferred from water to air through...Ch. 2 - 2.46 The wall of a liquid-to-gas heat exchanger...Ch. 2 - Prob. 2.47PCh. 2 - The handle of a ladle used for pouring molten lead...Ch. 2 - 2.50 Compare the rate of heat flow from the bottom...Ch. 2 - 2.51 Determine by means of a flux plot the...Ch. 2 - Prob. 2.52PCh. 2 - Determine the rate of heat transfer per meter...Ch. 2 - Prob. 2.54PCh. 2 - 2.55 A long, 1-cm-diameter electric copper cable...Ch. 2 - Prob. 2.56PCh. 2 - Prob. 2.57PCh. 2 - Prob. 2.58P
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
- Q2 A 2 kW resistance heater wire with thermal conductivity of k = 20 W/m °C, a diameter of D = 5 mm, and a length of L= 0.7 m is used to boil water. If the outer surface temperature of the resistance wire is Ts= 110°C, determine the temperature at the center of the wire. Q3: Consider a 20-cm-thick large concrete plane wall (k = 0.77 W/m °C) subjected to convection on both sides with T1 = 27°C and h₁ = 5 W/m² °C on the inside, and T2 = 8°C and h₂ = 12 W/m² °C on the outside. Assuming constant thermal conductivity with no heat generation and negligible radiation, (a) express the differential equations and the boundary conditions for steady one-dimensional heat conduction through the wall, (b) obtain a relation for the variation of temperature in the wall by solving the differential equation, and (c) evaluate the temperatures at the inner and outer surfaces of the wall. Ans: (a) Ans: 121.4 °C dT (L) -k dx -=h₂ [T(L)-T₂] (b) T(x) = 20-45.44x Q4: A double pane window consists of 3 mm thick…arrow_forward5. Consider a stainless-steel spoon (k = 8.7 Btu/h-ft-°F) partially immersed in boiling water at 200 °F in a kitchen at 75 °F. The handle of the spoon has a cross section of 0.08 in. × 0.5 in., and extends 7 in. in the air from the free surface of the water. If the heat transfer coefficient at the exposed surfaces of the spoon handle is 3 Btu/h ft².°F:arrow_forwardA house has a three meter deep basement (foundation) wall that is in a 10 meter by eight meter rectangular shape based on interior dimensions. On average, 2.5 meters of the wall is below grade. Assume the outside air temperature is 38°C and the inside temperature is 20°C; there is an average ground temperature of 27°C. Determine the rate of heat loss through the wall if it is insulated with an R-value of about 30°C.m^2/W.arrow_forward
- H.W. Q: An aluminum pan whose thermal conductivity is 237 W/m-°C has a flat bottom with diameter 20 cm and thickness 0.4 cm. Heat is transferred steadily to boiling water in the pan through its bottom at a rate of 800 W. If the inner surface of the bottom of the pan is at 105°C, determine the temperature of the outer surface of the bottom of the pan. 105°C 0.4 cm Answer: T= 105.43 °C 800 W 7arrow_forwardA food product with 82% moisture content is being frozen. Estimate the specific heat of the product at -8°C when 82% of the water is in a frozen state. The specific heat of dry product solid is 2.5 kJ/(kg °C). Assume specific heat of water at -10°C is similar to specific heat of water at 0°C.arrow_forwardQ3/A sphere of 30 mm diameter has its surface maintained at 80°C while being immersed in still water at 20°C. Determine the power required to maintain the temperature.arrow_forward
- In a double-glazed window, the panes of glass are separated by 1.0 cm and the space is filled with a gas with thermal conductivity 24 mW K−1 m−1. What is the rate of transfer of heat by conduction from the warm room (28 °C) to the cold exterior (−15 °C) through a window of area 1.0 m2? You may assume that one pane of glass is at the same temperature as the inside and the other as the outside. What power of heater is required to make good the loss of heat?arrow_forwardIt is designed in such a way that the internal temperature of a commercial heat treatment furnace can reach up to 165 oC. All surfaces of the furnace consist of firebrick (10 cm), insulation material and sheet metal (3mm) from the inside out. Given that the outdoor temperature is 22 oC, the outer sheet will be allowed to go up to 35 oC, which is a temperature that will not disturb in contact with hands. In this case, determine the insulation material thickness to be used. The thermal conductivity coefficient of the insulation material is insulation 0.066 W / m oC, 60 W / m oC for sheet metal and 115 W / m oC for firebrick. Indoor heat transfer coefficient will be accepted as 25 W / m2 oC and 12 W / m2 oC for outdoor environment.arrow_forwardHow long should it take to boil an egg? Model the egg as a sphere with radius of 2.3 cm that has properties similar to water with a density of = 1000 kg/m3 and thermal conductivity of k = 0.606 Watts/(mC) and specific heat of c = 4182 J/(kg C). Suppose that an egg is fully cooked when the temperature at the center reaches 70 C. Initially the egg is taken out of the fridge at 4 C and placed in the boiling water at 100 C. Since the egg shell is very thin assume that it quickly reaches a temperature of 100 C. The protein in the egg effectively immobilizes the water so the heat conduction is purely conduction (no convection). Plot the temperature of the egg over time and use the data tooltip in MATLAB to make your conclusion on the time it takes to cook the egg in minutes.arrow_forward
- The temperature of a gas stream is measured by a thermocouple whose junction can be approximated as a 1-mm-diameter sphere. Take the junction’s properties as: k of 32 W/m K, density of 8.2 kg/m^3, c of 300 J/Kg K. On its surface, the overall heat transfer coefficient is 200 W/m^2 K. Neglect any conduction loss from the sphere to other parts of the thermocouple. Create a plot of measurement error as a function of time for the thermocouple.arrow_forwardThe temperature of a gas stream is measured by a thermocouple whose junction can be approximated as a 1-mm-diameter sphere. Take the junction’s properties as: k of 32 W/m K, density of 8.2 kg/m^3, c of 300 J/Kg K. On its surface, the overall heat transfer coefficient is 200 W/m^2 K. Neglect any conduction loss from the sphere to other parts of the thermocouple. Create a plot of measurement error as a function of time for the thermocouple, expressed as a fraction of the initial temperature difference.arrow_forwardExample: 0.5 kg of water per minute is heated from 20° to 40°C when passed through a tube of 2.5 cm diameter steel pipe. The pipe surface temperature is maintained at 110°C by condensing steam on its surface. Find out the length of the pipe required. The properties of water at mean temperature of 70°C are given below: p = 978 kg/m² k= 0.575 W/m. K Cp = 4200 J/kg. K v = 0.415 x 10-6 m²/secarrow_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
Understanding Conduction and the Heat Equation; Author: The Efficient Engineer;https://www.youtube.com/watch?v=6jQsLAqrZGQ;License: Standard youtube license