Question

Consider a cube of density, specific heat, and thermal conductivity of 2700 kg/m3, 0.896 kJ/kg-K, and 204 W/m-K, respectively. The cube is 5 cm in length, and is initially at a temperature of 20 oC. For t>0, two of the boundary surfaces are insulated, two are subjected to uniform heating at a rate of 10,000 W/m2, and two dissipate heat by convection to an ambient temperature of 20 oC, with a heat transfer coefficient of 50 W/m2-K.

Assuming lumped capacitance is applicable, determine the time required for the cube to come to within 5 degrees of its steady-state temperature.

Answer #1

Consider a large uranium plate of thickness 5 cm and thermal
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(a) Sketch...

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a)express the differential equation and the boundary
conditions for steady one dimensional heat conduction through the
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b)obtain the relation for the variation of temperature
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c)evaluate the...

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A spherical object (50 cm diameter, c=0.46 kJ/kg*C, k = 42
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Some properties of glass are listed here.
Density: 2300 kg/m3
Specific heat: 840 J/kg·C°
Coefficient of linear thermal expansion: 8.5 × 10-6
(C°)-1
Thermal conductivity: 0.80 W/(m·C°)
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Some properties of glass are listed here....

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Homework-9
Due:
Q) A fuel plate is fabricated from 0.3 cm thick 1.5% enriched
uranium. The cladding is 0.25 mm 304 stainless steel. The coolant
saturation temperature is 260 oC. The
average thermal neutron flux is 2.5 X
1014
neutrons/cm2 /s. The surface
temperature of the clad is 350 oC.
Assume any missing data to answer the following questions:.
1) Write an expression of the heat generated per unit volume
2 What is the heat flux at the surface of...

After heat treatment, the 2-cm thick metal plates (k = 180
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coefficient is given as a function of the air velocity blowing over
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