Explanation Calculate the rate of heat transfer by convection. Q ˙ conv = h A Δ T = h ( π D 2 ) ( T s − T o ) (I) Here, change in the temperature is Δ T , surface temperature is T S , final temperature is T o , the diameter of a spherical ball is D , the convection heat transfer coefficient is h , and area of a spherical ball is A . Calculate the rate of heat transfer by radiation. Q ˙ rad = ε σ A ( T s 4 − T o 4 ) = ε σ ( π D 2 ) ( T s 4 − T o 4 ) (II) Here, surface temperature is T S , exit temperature is T o , emissivity of the ball is ε , and Stefan-Bolzmann constant is σ . Calculate the total rate of heat transfer from the ball. Q ˙ total = Q ˙ conv + Q ˙ rad (III) Conclusion: Substitute 15 W/m 2 ⋅ °C for h , 9 cm for D , 110 ° C for T S , and 20 ° C for T o in Equation (I). Q ˙ conv = 15 W/m 2 ⋅ °C ( π × ( 9 cm ) 2 ) ( 110 ° C − 20 ° C ) = 15 W/m 2 ( π × 81 cm 2 × ( 0.01 m cm ) 2 ) ( 90 ) = 34

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A fluid is a substance that is continuously deformed by the application of shear stress. The rate of deformation of a fluid depends on its viscosity. The fluid tries to flow when it interacts with some other system.

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Chapter 2.8, Problem 99P

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The total rate of heat transfer from the ball.

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The total rate of heat transfer from the ball.

Solution Summary: The author calculates the rate of heat transfer by convection and radiation.

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