Chapter 3, Problem 3.110P

Consider the manufacture of photovoltaic silicon, as described in Problem 1.42. The thin sheet of silicon is pulled from the pool of molten material very slowly and is subjected to an ambient temperature of $T_{\infty }=527°\text{C}$ within the growth chamber. A convection coefficient of $h=7.5{\text{W/m}}^{\text{2}}\cdot \text{K}$ is associated with the exposed surfaces of the silicon sheet when it is inside the growth chamber. Calculate the maximum allowable velocity of the silicon sheet $V_{si}.$ The latent heat of fusion for silicon is $h_{sf}=1.8\times {10}^6\text{J/kg}\text{.}$ It can be assumed that the thermal energy released due to solidification is removed by conduction along the sheet.