As an engineer working for a large military firm, you are testing the effectiveness of a heat gun on various materials. The situation is shown in Figure P6.44. This gun shines a light on the surface and heats up the material. As an engineer, you want to know how much this heat gun can penetrate its heat through specific materials. For material 1, the thermal diffusivity is \(10 \mathrm{~m}^{2} / \mathrm{s}\) and for material 2, the thermal diffusivity is \(12 \mathrm{~m}^{2} / \mathrm{s}\). Both materials are infinitely long and are at a temperature of \(0^{\circ} \mathrm{C}\). The gun heats up the surface to a temperature of \(T_{i}\).

a. Calculate the penetration depth at \(t=10 \mathrm{~s}\) for both material 1 and material 2.

Transcribed Image Text:

FIGURE P6.44 z=0 q" T=T a 10 m/s or 12 m/s = T-T