A plane wall of thickness 0.1 m and thermal conductivity 25 W/m-K having uniform volumetric heat generation of 0.3 MW/m³ is insulated on one side, while the other side is exposed to a fluid at 92°C. The convection heat transfer coefficient between the wall and the fluid is 500 W/m² K. Determine the maximum temperature in the wall. Answer: 212°C

A plane wall of thickness 0.1 m and thermal conductivity 25 W/m-K having uniform volumetric heat generation of 0.3 MW/m³ is insulated on one side, while the other side is exposed to a fluid at 92°C. The convection heat transfer coefficient between the wall and the fluid is 500 W/m² K. Determine the maximum temperature in the wall. Answer: 212°C

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.38P: 2.38 The addition of aluminum fins has been suggested to increase the rate of heat dissipation from...

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To warm up some milk in a thin-walled glass cylindrical container whose diameter is 6 cm. The height of the milk in the glass is 7 cm. The milk container is placed into a large pan filled with hot water at 60°C. The milk is stirred constantly, so that its temperature is uniform at all times. If the heat transfer coefficient between the water and the glass is 120 W/m2.°C, determine how long it will take for the milk to warm up from 3°C to 38°C. Take the properties of the milk to be the same as those of water. Can the milk in this case be treated as a lumped system? Use the lumped system analysis to solve the problem. The properties of water and milk at 20°C are, k = 0.607 W/m.°C,p=998 kg/m', and C, = 4.182 kJ/kg.°C. Answer: 5.8 min. ملاحظه: تكون هنا قيمة (0.1 < Bi( ويفترض لايطبق التحليل الكتلي , ولكن استخدم نفس التحليل والمعادلات في المحاضرة وكذلك في المثال لان الحليب يخلط باستمرار ولذلك تكون درجة حرارته منتظمه و متغيره مع الزمن لانه يكتسب حراره من الماء ويسخن وترتفع درجة حرارته مع…
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Rock has often been suggested as a medium for the thermal storage of energy.A cylindrical piece of rock with diameter 10 m and height 20 m is used for thestorage of thermal energy. The rock is insulated and has an average heattransfer coefficient, U = 0.28 kW/m2 K. The density of the rock material is2,650 kg/m3 and its specific heat capacity is 0.72 kJ/kgK. The temperature ofthe rock is raised to 500C and the ambient temperature is 25C. Determine:a) The total energy stored in the rock in MWh.b) The temperature of the rock 12 h after the heating process stops.c) The heat that has escaped from the rock during this 12 h period.d) The loss of exergy of the rock during this 12 h period.
700 W/m3 electrical heat is generated in a large plane wall whose one side is insulated while the other side is subjected to convection. The thermal conductivity of the wall is (k W/m.K) and the convection heat transfer coefficient is (h = 17 W/m?K). Determine the location and the value for the maximum temperature and the minimum temperature in the plate for steady one-dimensional heat transfer. Assume T. = 25°C. A=1 m?; L= 25 cm). = 20