Question: Air flows from a large chamber in which the pressure and temperature are maintained at 100 psia and 500°R, respectively, through a convergent-divergent nozzle and then into a constant diameter insulated pipe that in turn discharges into another large chamber in which the pressure is kept constant. The ratio of the nozzle exit area to the throat area of the nozzle is 3. The pipe has a diameter of 1 ft and a length of that is equal to 15 times its diameter. A friction factor of 0.005 can be assumed for the pipe flow. The pipe discharges into another large chamber in which the pressure, the back-pressure, is kept constant. A normal shock wave occurs in the pipe at a distance equal to 3 times the pipe diameter downstream of the nozzle exit. Assuming isentropic flow in the nozzle and Fanno flow in the pipe, determine the back-pressure. Sketch the process that occurs in this flow system on a Fanno line. Also, sketch the pressure variation along the length of the flow system.