Water and ammonia streams flow through a steady state heat exchanger. The water stream enters the heat exchanger with a velocity of 40 m/s, a temperature of 200°C, and a pressure of 15 bar through a pipe with a diameter of 0.1 m. The water stream leaves as a saturated liquid-vapor mixture with a quality of 0.2. Before entering the heat exchanger, the ammonia stream flows through a throttling valve. At the inlet of the throttling valve the ammonia pressure and temperature are 12 bar and 28°C. At the exit the pressure of the ammonia stream has dropped to 4 bar. The stream then enters the heat exchanger and exits with a temperature of 60°C. The pressure drop across the heat exchanger is negligible for both the ammonia and water streams. Neglect heat transfer to the surroundings.
(a) Determine the mass flow rate (kg/s) of the water stream.
(b) Determine the mass flow rate (kg/s) of the ammonia stream.
(c) Determine the state of the ammonia after the throttling process. If the ammonia is a saturated liquid-vapor mixture, calculate the quality x2.