In a bread-making factory, a 10-kW oven has a hearth area of 4 m2 and operates at 215 ºC. It is loaded with two batches of bread dough in baking tins; 140 loaves on the first batch and 112 loaves on the second batch. The surface of each loaf measures 14 cm x 25 cm. Assuming that the emissivity of dough is 0.85, that the dough bakes at 110 ℃, and that 92% of the heat is transmitted in the form of radiant energy, calculate the efficiency of energy use (as the percentage of the supplied radiant energy which is absorbed by the food) for each batch.

In a bread-making factory, a 10-kW oven has a hearth area of 4 m2 and operates at 215 ºC. It is loaded with two batches of bread dough in baking tins; 140 loaves on the first batch and 112 loaves on the second batch. The surface of each loaf measures 14 cm x 25 cm. Assuming that the emissivity of dough is 0.85, that the dough bakes at 110 ℃, and that 92% of the heat is transmitted in the form of radiant energy, calculate the efficiency of energy use (as the percentage of the supplied radiant energy which is absorbed by the food) for each batch.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.56P

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