An ordinary egg can be approximated as a 5.5-cm-diameter sphere whose thermal conductivity of roughly W } mk k = 0.6 overall density of p = 1000 kg and heat capacity of C₂ = m² = 90°C The egg is initially at a uniform temperature of T₁ = 10°C and is dropped into boiling water at T Taking the convective heat transfer coefficient to be h = 10- -determine how long it will take for the egg to W m²K reach T = 70°C. In solving this problem, please use the lump model method (ignoring the requirement of small Biot number and discuss the outcomes, In solving the problem, please follow the steps below. For the Lump Model 3000 = 3000K 1. Compute the volume and surface area of the sphere (as the egg model) 2. Compute the characteristic length Lc Vol As 3. Compute the diffusivity a = k PCp =

An ordinary egg can be approximated as a 5.5-cm-diameter sphere whose thermal conductivity of roughly W } mk k = 0.6 overall density of p = 1000 kg and heat capacity of C₂ = m² = 90°C The egg is initially at a uniform temperature of T₁ = 10°C and is dropped into boiling water at T Taking the convective heat transfer coefficient to be h = 10- -determine how long it will take for the egg to W m²K reach T = 70°C. In solving this problem, please use the lump model method (ignoring the requirement of small Biot number and discuss the outcomes, In solving the problem, please follow the steps below. For the Lump Model 3000 = 3000K 1. Compute the volume and surface area of the sphere (as the egg model) 2. Compute the characteristic length Lc Vol As 3. Compute the diffusivity a = k PCp =

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.28P

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