Steam

Question 1

For which of the following ideal processes, if any, is the fluid outlet enthalpy greater than the fluid inlet enthalpy? (Assume horizontal fluid flow in each process.)
(A) Cooling water flowing through a fixed convergent nozzle.
(B) Cooling water flowing through an operating lube oil heat exchanger

Answer 1

(B) Cooling water flowing through an operating lube oil heat exchanger.

Question 2

For which of the following ideal processes, if any, is the steam inlet enthalpy equal to the steam outlet enthalpy? (Assume horizontal fluid flow in each process.)
(A) Dry saturated steam flowing through a pressure reducing valve.
(B) Dry saturated steam flowing through a fixed convergent nozzle

Answer 2

(A) Dry saturated steam flowing through a pressure reducing valve

Question 3

Two identical pressurizers are connected to the same location on two identical reactor coolant systems operating at 1,000 psia. Pressurizer A volume contains 50 percent saturated water and 50 percent saturated steam. Pressurizer B volume contains 50 percent subcooled water (at 300°F) and 50 percent nitrogen.
Which pressurizer will maintain the higher pressure following a sudden 10 percent liquid outsurge from each pressurizer, and why?

Answer 3

Pressurizer A due to vaporizing of saturated water as pressure begins to decrease

Question 4

Two identical pressurizers are connected to the same location on two identical reactor coolant systems operating at 1,000 psia. Pressurizer A volume contains 50 percent subcooled water (at 300°F) and 50 percent nitrogen. Pressurizer B volume contains 50 percent saturated water and 50 percent saturated steam.
Which pressurizer will maintain the higher pressure during a sudden 10 percent liquid outsurge from each pressurizer, and why?

Answer 4

Pressurizer B due to vaporizing of saturated water as pressure begins to decrease