Question

Consider the manufacture of photovoltaic silicon where a thin sheet of silicon is pulled from the pool of molten material very slowly and is subjected to an ambient temperature of T 627°C within the growth chamber. The silicon sheet is Wsi =85 mm wide and tsi =150um thick. A convection coefficient of h 7.5 W/m2.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 Vsi. The latent heat of fusion for silicon is hgf = 1.8 x 10° J/kg. It can be assumed that the thermal energy released due to solidification is removed by conduction along the sheet. Physical Properties Mathematical Functions Step 1 Determine the melting temperature of silicon, in K. Tmp.si = i K Attempts: 0 of 3 used Save for Later Check Answer Step 2 Determine the thermal conductivity of silicon for this problem, in W/m-K. k= W/m-K Step 3 Determine the rate of heat transfer from the silicon sheet, in W cond Attempts: 0 of 3 used Save for Later Check Answer Step 4 Determine the maximum allowable velocity of the silicon sheet, in mm/min. Vi i mm/min

Answer 1

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