A very long, rectangular cross-section block is made from metal with the following properties: thermal conductivity = 130 W/mK, density = 2771 kg/m³, and specific heat capacity = 703 J/kgK. Initially all 4 sides of the cross section are maintained at 373 K. Then the temperature of one side is suddenly increased to 473 K. The temperature profile in the block will be investigated using an explicit finite difference model. If the time step is fixed at 5.5 seconds, what is the limit for node spacing that should be used to ensure stability of the solution? Give your numerical answer in mm to 1 decimal place.

A very long, rectangular cross-section block is made from metal with the following properties: thermal conductivity = 130 W/mK, density = 2771 kg/m³, and specific heat capacity = 703 J/kgK. Initially all 4 sides of the cross section are maintained at 373 K. Then the temperature of one side is suddenly increased to 473 K. The temperature profile in the block will be investigated using an explicit finite difference model. If the time step is fixed at 5.5 seconds, what is the limit for node spacing that should be used to ensure stability of the solution? Give your numerical answer in mm to 1 decimal place.

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.29P

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