Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470917855
Author: Bergman, Theodore L./
Publisher: John Wiley & Sons Inc
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Chapter 5, Problem 5.15P
Carbon steel (AISI 1010) shafts of 0.1-m diameter are heat treated in a gas-fired furnace whose gases are at 1200K and provide a convection coefficient of
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B6
A 50-mm thick plate of carbon steel (AISI 1010) is annealed with a reheat stage taking the steel from its initial uniform temperature of 200 C to a minimum final temperature of 550 C. HEating is effected in a gas-fired furnace where products of combustion at Tamb = 800 C maintain a convection coefficient of h = 100 W/m^2K on both sides of the plate. How long should the plate be left in the furnace? Substantiate with relevant analysis and calculations.
Carbon steel (AISI 1010) shafts of 0.15-m diameter are heat treated in a gas-fired furnace whose gases are
at 1000 K and provide a convection coefficient of 90 W/m²K. If the shafts enter the furnace at 300 K, how
long must they remain in the furnace to achieve a centerline temperature of 800 K? (k=51.2 W/mK, c=541
J/kgK, p=7832 kg/m³, a=1.21x10-5 m²/s)
a. 2802 s
O b. 1732 s
О с. 1636 s
O d. 2212 s
e. 1558 s
Chapter 5 Solutions
Fundamentals of Heat and Mass Transfer
Ch. 5 - Consider a thin electrical heater attached to a...Ch. 5 - The inner surface of a plane wall is insulated...Ch. 5 - A microwave oven operates on the principle that...Ch. 5 - A plate of thickness 2L, surface area As, mass M,...Ch. 5 - For each of the following cases, determine an...Ch. 5 - Steel balls 12 mm in diameter are annealed by...Ch. 5 - Consider the steel balls of Problem 5.6, except...Ch. 5 - The heat transfer coefficient for air flowing over...Ch. 5 - A solid steel sphere (AISI 1010), 300 mm in...Ch. 5 - A flaked cereal is of thickness 2L=1.2mm. The...
Ch. 5 - The base plate of an iron has a thickness of L=7mm...Ch. 5 - Thermal energy storage systems commonly involve a...Ch. 5 - A tool used for fabricating semiconductor devices...Ch. 5 - A copper sheet of thickness 2L=2mm has an initial...Ch. 5 - Carbon steel (AISI 1010) shafts of 0.1-m diameter...Ch. 5 - A thermal energy storage unit consists of a large...Ch. 5 - Small spherical particles of diameter D=50m...Ch. 5 - A spherical vessel used as a reactor for producing...Ch. 5 - Batch processes are often used in chemical and...Ch. 5 - An electronic device. such as a power transistor...Ch. 5 - Molecular electronics is an emerging field...Ch. 5 - A plane wall of a furnace is fabricated from plain...Ch. 5 - A steel strip of thickness =12mm is annealed by...Ch. 5 - In a material processing experiment conducted...Ch. 5 - Plasma spray-coating processes are often used to...Ch. 5 - The plasma spray-coating process of Problem 5.25...Ch. 5 - A chip that is of length L=5mm on a side and...Ch. 5 - Consider the conditions of Problem 5.27. 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