(Adv.) Develop a program that will track the process in time as described in Problems 15.51 and 15.53. Investigate the time it takes to bring the tank pressure to 125 kPa as a function of the size of the nozzle exit area. Plot several of the key variables as functions of time.
Problems 15.51
A 1-m3 insulated tank contains air at 1 MPa, 560 K. The air in the tank is now discharged through a small convergent nozzle to the atmosphere at 100 kPa. The nozzle has an exit area of 2 × 10-5 m2.
a. Find the initial mass flow rate out of the tank.
b. Find the mass flow rate when half of the mass has been discharged.
Problems 15.53
Air flows into a convergent-divergent nozzle with an exit area 2.0 times the throat area of 0.005 m2. The inlet stagnation state is 1.2 MPa, 600 K. Find the back pressure that will cause a reversible supersonic exit flow with M = 1 at the throat. What is the mass flow rate?