. A 20 mm diameter sphere made of aluminum alloy 2024 initially at a uniform temperature...

. A 20 mm diameter sphere made of aluminum alloy 2024 initially at a uniform temperature of 500 ºC is suddenly immersed in a saturated water bath maintained at atmospheric pressure. The surface of the sphere has an emissivity or 0.25. Determine.

a.) the total heat transfer coefficient for this initial condition, and

b.) what fraction of the total coefficient is contributed by radiation. (~180 W/m2 -K, ~ 7%)

Expert Solution

samet mamat answered 2 years ago

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