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
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Chapter 2, Problem 2.18P
Estimate the rate of heat loss per unit length from a 5-cm ID, 6-cm OD steel pipe covered with high-temperature insulation having a thermal conductivity of 0.11 W/(m K) and a thickness of 1.2 cm. Steam flows in the pipe. It has a quality of 99% and is at
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1. Saturated steam at 500 K flows in a 0.20 m inside diameter, 0.21 m outside
diameter pipe. The pipe is covered with 0.075 m of insulation with a thermal
conductivity of 0.10 W/m-K. The pipe's conductivity is 52 W/m-K. The ambient
temperature is 300 K. The unit convective coefficients are hi = 18,000 W/m²-K and
ho 12 W/m²-K. Determine the heat loss (kJ/min) from 5 m of pipe.
i. A very long rod 5 mm in diameter has one end maintained at 100 oC. The surface of the rod is exposed to ambient air at 25 oC with convection heat transfer coefficient of 100 W/m2-K and thermal conductivity is 180 W/m-K. Determine the temperature distribution along the rod and What is the heat loss.
ii. Water flows on the inside of a steel pipe with an ID of 2.5 cm. The wall thickness is 2 mm, and the convection coefficient on the inside is 500 W/m2◦C. The convection coefficient on the outside is 12 W/m2 ◦C. Calculate the overall heat-transfer coefficient.
Soru 1
A steel pipe (k=43 W/m.K) has inner and outer diameters are 5 cm and 6 cm,
Henüz
respectively. The pipe is covered with high temperature insulation material. Thermal
cevaplanmadı
conductivity and thickness of the insulation are 0.11 W/m.K and 0.012 m, respectively.
Steam at 115,82°C flows in the pipe. The unit thermal resistance at the inner wall is
0.0026 m2.K/W. The heat transfer coefficient at the outer surface is 17 W/m2.K. The
35,00 üzerinden
işaretlenmiş
P Soruyu
işaretle
ambient temperature is 55,54°C. Estimate the rate of heat loss per unit length (W/m).
Yanıt:
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
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