Question : Calculate the heating time when four such boards are stacked together.Note 1: Don’t use Heissler charts to answer this question.Note 2: You’re free to make assumptions regarding any value you think you need in order to solve the problem. Just explain your reasoning behind your assumption in a logical manner.Note3: please explain clearly and step by step Heat sterilization of lumber, timbers, and pallets is used to kill insects toprevent their transfer between countries in international trade. This is analogous tofood sterilization by heat. A typical requirement here is that the slowest heating pointof any wood configuration be held at 56 °C for 30 minutes. Consider hot air heating ofwooden boards that maintains their surface temperature at 70 °C. The boards arestacked outside and in the winter time they can be considered to be at 0 °C when theyare brought in for heating. The thermal diffusivity of the wood is 9*10-8 m?/s.

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Question : Calculate the heating time when four such boards are stacked together. Note 1: Don’t use Heissler charts to answer this question. Note 2: You’re free to make assumptions regarding any value you think you need in order to solve the problem. Just explain your reasoning behind your assumption in a logical manner. Note3: please explain clearly and step by step

Question : Calculate the heating time when four such boards are stacked together. Note 1: Don’t use Heissler charts to answer this question. Note 2: You’re free to make assumptions regarding any value you think you need in order to solve the problem. Just explain your reasoning behind your assumption in a logical manner. Note3: please explain clearly and step by step

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 8.14P

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A food product wants to be produced in a small round shape (pellet) by freezing it in a water blast freezer freezer. Air freezer operates at a temperature of -35 ° C. The initial product temperature is 25 ° C. The pellet has a diameter of 0.5 cm, and a density of 980 kg / m³. The initial freezing temperature is -2.5 ° C. The latent heat of freezing of the product is 280 kJ / kg. The thermal conductivity of the frozen product is 1.9 W / (m ° C). The convective heat transfer coefficient is 50 W / (m² K). Calculate the freeze time. t f = hour.