Question

In: Mechanical Engineering

A 50 cm *50 cm copper slab 6.25 mm thick has uniform temperature of 300℃. Its...

A 50 cm *50 cm copper slab 6.25 mm thick has uniform temperature of 300℃. Its temperature is suddenly lowered to 36℃. (quenched in water)

Take

The conductivity k=370 W/mK, the density rho=9100 kg/m³, the specific heat c=0.38 kJ/kg℃, the convection coefficient h=90 W/m²℃.

1. Calculate the surface area, As

2. Calculate the volume, V.

3. Calculate the characteristic length, Lc

4. Calculate the Biot number, Bi

5. Calculate the thermal diffusivity, α (alpha)

6. Calculate the constant of time, τ (tau)

7. Calculate the time required for the plate to reach the temperature of , t₁

8. Calculate the time required for the plate to reach the temperature of , t2

9. Calculate the temperature at the surface at time 100 s, Ts2

10. Calculate the total energy transferred from this plate during the first 100 s, Q

Expert Solution

I have solved problem using concept of transient heat conduction. According to answering guidelines I have answered only first four parts. Each concept and step with proper reason is explained.Go through complete solution step by step and if u find it helpful then hit thumbs up and share feedback. Thanks

samet mamat answered 3 months ago

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