A potato (regard as a 10 cm diameter sphere) is placed in an air fryer and...

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A potato (regard as a 10 cm diameter sphere) is placed in an air fryer and subjected to an air flow at 200°C. The conductive heat transfer coefficient for a potato is about 1 W.m-¹.K-1, its density is 1070 kg.m³, its heat capacity is 3.48 kJ.kg-¹.K-1 and the convective heat transfer coefficient at its surface is 10 W.m-².K- 1. (a) Determine whether the potato as a thermal system can be described using lumped analysis (b) In what ways is your result in (a) consistent with the traditional expression 'hot potato'? In what ways is it not consistent with the expression? (c) What is the rate of heat loss from the potato by radiation once it reaches steady state? Treat the potato as a 'grey body' with emissivity 0.6. A potato (regard as a 10 cm diameter sphere) is placed in an air fryer and subjected to an air flow at 200°C. The conductive heat transfer coefficient for a potato is about 1 W.m-¹.K-1, its density is 1070 kg.m³, its heat capacity is 3.48 kJ.kg-¹.K-1 and the convective heat transfer coefficient at its surface is 10 W.m-².K- 1. (a) Determine whether the potato as a thermal system can be described using lumped analysis (b) In what ways is your result in (a) consistent with the traditional expression 'hot potato'? In what ways is it not consistent with the expression? (c) What is the rate of heat loss from the potato by radiation once it reaches steady state? Treat the potato as a 'grey body' with emissivity 0.6.

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a The potato can be described using lumped analysis because it is a small homogeneous object with a ... View the full answer