1. Steel balls are to be heated in a furnace from an initial temperature of T1 = 50C to a final temperature of T2 = 900 C. The process calls for 800 steel balls per minute to be heated. Each steel ball has a radius of 1 cm. What is the rate that heat must be transferred from the furnace to the steel balls? Assume the density and specific heat of the balls are given to be ρ = 8085 kg/m3 and cp = 0.480 kJ/kg°C.
2. Steam at a pressure of P = 10 MPa, and temperature of T = 600 C is supplied at a rate of 100 kg/s. What is the velocity of the steam if the pipe carrying it has a diameter of 1 m?
3. Air flows into the 1 m2 inlet of an aircraft engine at a velocity of 200 m/s, a temperature of Ti = 30 C and a pressure of Pi = 100 kPa. The exhaust exits the engine at a temperature of Te = 1000 C and a pressure of Pe = 100 kPa. What are the volumetric flow rates at the engine's inlet and exit?
4. Air flows steadily through a diverging diffuser. The inlet area of the diffuser is 0.01 m2, and the mass flow rate into the diffuser is 3.0 kg/s. The pressure and temperature of the air as it enters the diffuser are Pi = 300 kPa and Ti = 100 C. The air leaves the diffuser with a velocity that is low compared to the inlet velocity. Determine the temperature of the air leaving the diffuser. Assume the diffuser is well insulated. For air R = 0.287 kJ/kgK