A long 0.6-m-OD 347 stainless steel (k = 14 W/(m K) cylindrical billet at 16?C room temperature is placed in an oven where the temperature is 260?C. If the average heat transfer coefficient is 170 W/(m2 K), (a) estimate the time required for the center temperature to increase to 323?C by using the appropriate chart and (b) determine the instantaneous surface heat flux when the center temperature is 232?C.GIVENA long cylindrical billet placed in an ovenBillet outside diameter = 0.6 mThermal conductivity (k) = 14 W/(m K)Initial temperature (Ti) = 16?COven temperature (T??) = 260?CThe average heat transfer coefficient (hc ) = 170 W/(m2 K)Center temperature increases to 232?CASSUMPTIONSRadial conduction only in billetUniform and constantproperties

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D= 0.8 m Blet Oven T-- 260°C