A flat plate’s surface temperatures are initially at 120 oC and 60 oC with one surface’s...

A flat plate’s surface temperatures are initially at 120 oC and 60 oC with one surface’s temperature being lower due to air at 20 oC flowing over it with a velocity of 2m/s having a heat transfer coefficient of 30 W/m2×K. The thermal conductivities of the sheet metal and air are 35 W/m×K and 0.0262 W/m×K, respectively

a. What are the modes of heat transfer?

b. Is this a time dependent or steady state problem? Why or why not?

c. Is this a 1-D, 2-D or 3-D problem? Why or why not?

d. The thermal conductivities in the sheet metal and air are significantly different. Recalling the definition

of thermal conductivity, what can you conclude about the materials’ abilities to transfer heat?

e.How would the heat transfer in the system differ if the cooling was through natural convection?

Explain your reasoning.

f. Draw a schematic of the energy flow.

g.Write down the energy balances to determine the temperature gradient at the top surface of the plate.

Do not solve.

Solutions

Expert Solution

samet mamat answered 5 months ago

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