A metal spherical tank is filled with chemicals undergoing an exothermic reaction. The reaction provides a uniform heat flux on the inner surface of the tank. The tank has an inner diameter of 5 m, and its wall thickness is 10 mm. The tank vall has a variable thermal conductivity given as
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HEAT+MASS TRANSFER ACCESS CODE
- 2.55 A long, 1-cm-diameter electric copper cable is embedded in the center of a 25-cm-square concrete block. If the outside temperature of the concrete is 25oC and the rate of electrical energy dissipation in the cable is 150 W per meter length, determine temperatures at the outer surface and at the center of the cable.arrow_forwardOn a multi-layered square wall, the thermal resistance of the first layer is 0.005 ° C / W, the resistance of the second layer is 0.3 ° C / W, and the third layer is 0.1 ° C / W. The overall temperature gradient in the wall is multilayered from one side. to the other side is 50 ° C. a. Determine the heat flux through the walls. = Answer watts / m2. b. If the thermal resistance of the second layer is changed to 0.1 ° C / W, what is the effect in% on heat flux, assuming the temperature gradient remains the same? = AnswerAnswer %.arrow_forwardOn a multi-layered rectangular wall, the thermal resistance of the first layer is 0.005 ° C / W, the resistance of the second layer is 0.2 ° C / W, and the third layer is 0.1 ° C / W.The overall temperature gradient in the wall is multilayered from one side. to the other side is 50 ° C. a. Determine the heat flux through the walls. = Answer watts / m2. b. If the thermal resistance of the second layer is changed to 0.3 ° C / W, what is the effect in% on heat flux, assuming the temperature gradient remains the same? = AnswerAnswer %.arrow_forward
- The wall of a refrigerator is made of fiberglass insulation (k = 0.035 W/mK) glued between two 1 mm thick layers of metal plate (k = 15.1 W/mK). The refrigerated space is kept at 2°C, and the average heat transfer coefficients on the inner and outer wall surfaces are 4 W/m²K and 9 W/m²K, respectively. The average temperature in the kitchen is 24°C. It is observed that condensation occurs on the external surface of the refrigerator when the temperature of the external surface drops to 20°C. Determine the minimum thickness of fiberglass insulation that should be used on the wall to prevent condensation on the outside surface.arrow_forwardQ1 / A5 - cm - diameter steel pipe is covered with a 1 - cm layer of insulating material having k = 0.22 W / m . ° C followed by a 3 - cm - thick layer of another insulating material having k = 0.06 W / m . ° C . The system is exposed to a convection surrounding condition of h = 60 W / m² . ° C and T -15 ° C . The outside surface temperature of the steel pipe is 400 ° C . Calculate the heat lost by the pipe - insulation assembly for a pipe length of 20 m . Express in Watts .arrow_forwardA 15 mm diameter cylindrical nuclear fuel rod is housed in a hollow ceramic cylinder concentric to the rod with an inner diameter of 35 mm and an outer diameter of 110 mm. This creates an air gap between the fuel rod and the hollow ceramic cylinder with a convective heat transfer coefficient of 10 W/m²·K. The hollow ceramic cylinder has a thermal conductivity of 0.07 W/m·K and its outer surface maintains a constant temperature of 30 °C. If the fuel rod generates heat at a rate of 1 MW/m³. Solving, the temperature at the surface of the fuel rod is 1026°C. I need the solution with fundamental concepts (Textically with definitions) of how the heat flow behaves in the system. NOT THE MATHEMATICAL RESOLUTION. I already know how to solve it.arrow_forward
- A 15 mm diameter cylindrical nuclear fuel rod is housed in a hollow ceramic cylinder concentric to the rod with an inner diameter of 35 mm and an outer diameter of 110 mm. This creates an air gap between the fuel rod and the hollow ceramic cylinder with a convective heat transfer coefficient of 10 W/m²·K. The hollow ceramic cylinder has a thermal conductivity of 0.07 W/m·K and its outer surface maintains a constant temperature of 30 °C. If the fuel rod generates heat at a rate of 1 MW/m³. Solving, the temperature at the surface of the fuel rod is 1026°C. Explain how the heat flow behaves in the system, using the fundamental concepts.arrow_forwardA 15 mm diameter cylindrical nuclear fuel rod is housed in a hollow ceramic cylinder concentric to the rod with an inner diameter of 35 mm and an outer diameter of 110 mm. This creates an air gap between the fuel rod and the hollow ceramic cylinder with a convective heat transfer coefficient of 10 W/m²·K. The hollow ceramic cylinder has a thermal conductivity of 0.07 W/m·K and its outer surface maintains a constant temperature of 30 °C. If the fuel rod generates heat at a rate of 1 MW/m³. Solving, the temperature at the surface of the fuel rod is 1026°C. Give the solution from fundamental concepts of how the heat flow behaves in the system.arrow_forwardA 15 mm diameter cylindrical nuclear fuel rod is housed in a hollow ceramic cylinder concentric to the rod with an inner diameter of 35 mm and an outer diameter of 110 mm. This creates an air gap between the fuel rod and the hollow ceramic cylinder with a convective heat transfer coefficient of 10 W/m²·K. The hollow ceramic cylinder has a thermal conductivity of 0.07 W/m·K and its outer surface maintains a constant temperature of 30 °C. If the fuel rod generates heat at a rate of 1 MW/m³. Determine the temperature at the surface of the fuel rod. Note: Give the solution from fundamental concepts of how the heat flow behaves in the systemarrow_forward
- Two identical aluminum plates with thickness of 30 cm are pressed against each other at an average pressure of 1 atm. The interface, sandwiched between the two plates, is filled with glycerin. On the left outer surface, it is subjected to a uniform heat flux of 7800 W/m2 at a constant temperature of 50°C. On the right outer surface, the temperature is maintained constant at 30°C. Determine the thermal contact conductance of the glycerin at the interface, if the thermal conductivity of the aluminum plates is 237 W/m∙K. Discuss whether the value of the thermal contact conductance is reasonable or notarrow_forwardPosting it second time . Answer all else dont answer - You are using a silver spoon to stir water that just started boiling so that you can achieve a more even heat distribution in your water. The spoon is partially immersed in boiling water and a thermometer in your kitchen reads 27 °C. The handle of the spoon has a cross section of 2mm × 1cm and extends 15 cm in the air from the free surface of the water. The heat transfer coefficient at the exposed surfaces of the spoon handle is 3 W/m2 ×K. Part A : Determine the temperature difference across the exposed surface of the spoon handle. Follow the problem-solving guide on the front page. At the minimum, your analysis should answer the following questions providing detailed justifications:-What are the modes of heat transfer that the spoon is exposed to? -Is this a time dependent or steady state problem? Why or why not?-Is this a 1-D, 2-D or 3-D problem? Why or why not?- What is the thermal conductivity of the material?- The heat…arrow_forwardThe furnace wall shown in the figure is made of a material with a thermal conductivity of 5 W / m ° C, the radiant emission coefficient of the outer surface of the wall is 0.95, Stefan Boltzman constant is 5.67x104 W / m ^ 2 (K ^ 4), ambient temperature and air temperature 297 K is. The heat transfer coefficient between the outer surface of the wall and the air is h = 20 W / m (K ^ 2). Wall inner surface temperature 573 K, outer surface temperature 308 K Since the value is kept constant a) Find the layer thickness of the wall? b) Find the layer thickness of the wall if the moving fluid medium on the outer surface of the wall is corroded?arrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning