Chvorinov and Caine gave rules for solidification time and freezing ratio for a riser. Using these rules or otherwise find the size of a cylindrical riser of height to diameter ratio as one for a steel casting of size 250$\times$
250$\times$50 mm3, when the casting is fed horizontally and riser is a side one. Thickness of the casting is 50 mm. For steel a = 0.10, b = 0.03 and c = 1.00. Consider it as a long bar of cross-section 250$\times$50.