Cooling analysis of aluminum extrusion (forced convection, transient conduction): determine the minimum time required for an aluminum extrusion to cool to a maximum internal temperature of 40 °c. the extrusion has a square cross section of 4 cm x 4 cm and exits the extruder at a uniform temperature of 150 °c. 20 °c air can be directed towards the extrusion at a velocity of 15 m/s.

An open feedwater heater operates at steady state with liquid entering at inlet 1 with t? = 40°c and pl = 1 .2 mpa. water vapor att2-200°c and p2 = 1.2 mpa enters at inlet 2. saturated liquid water exits with a pressure of pa 1.2 mpa. neglect heat transfer with the surroundings and all kinetic and potential energy effects, determine the mass flow rate of steam at inlet 2 if the mass flow rate of liquid water at inlet 1 is given as 2 kg/s.