Fluid Statistics and Dynamics Flashcards
The possibility of water hammer in a liquid system is minimized by…
A. maintaining temperature above the saturation temperature.
B. starting centrifugal pumps with the casing vent valve fully open.
C. starting positive displacement pumps with the discharge valve closed.
D. venting systems prior to starting centrifugal pumps.
venting systems prior to starting centrifugal pumps.
Which one of the following methods will increase the possibility and/or severity of water hammer?
A. Opening and closing system valves slowly.
B. Venting fluid systems prior to starting a pump.
C. Starting a centrifugal pump with the discharge valve fully open.
D. Starting a centrifugal pump with the discharge valve fully closed
Starting a centrifugal pump with the discharge valve fully open.
A sudden stop of fluid flow in a piping system, due to rapid closure of an isolation valve, will most
likely result in…
A. check valve slamming.
B. pump runout.
C. water hammer.
D. pressurized thermal shock
water hammer.
One reason for keeping condensate out of the steam lines is to…
A. minimize corrosion buildup.
B. reduce heat losses.
C. eliminate steam traps.
D. prevent water/steam hammer
prevent water/steam hammer
The possibility of water hammer will be increased by…
A. maintaining the discharge line filled with liquid on an automatically starting pump.
B. condensation in a steam line just prior to initiating flow.
C. warming steam lines prior to initiating steam flow.
D. slowly closing the discharge valve on an operating pump
condensation in a steam line just prior to initiating flow.
To minimize the possibility of water hammer when initiating flow in a system, the operator should…
A. vent the system prior to initiating flow.
B. vent the system only after flow has been initiated.
C. fully open the pump discharge valve prior to starting a pump.
D. rapidly open the pump discharge valve after the pump is running.
vent the system prior to initiating flow.
Which one of the following describes why large steam lines are gradually warmed instead of suddenly
admitting full steam flow?
A. To minimize the possibility of stress corrosion cracking of the steam lines.
B. To minimize the total thermal expansion of the steam lines.
C. To minimize the potential for water hammer in the steam lines.
D. To minimize the heat loss from the steam lines.
To minimize the potential for water hammer in the steam lines.
Which one of the following will minimize the possibility of water hammer?
A. Draining the discharge line of a centrifugal pump prior to starting the pump.
B. Draining condensate out of a steam lines before initiating flow.
C. Starting a centrifugal pump with its discharge valve fully open.
D. Starting a positive displacement pump with its discharge valve partially closed.
Draining condensate out of a steam lines before initiating flow.
Which one of the following operating practices minimizes the possibility of water hammer?
A. Change valve positions as rapidly as possible.
B. Start centrifugal pumps with the discharge valve throttled.
C. Start positive displacement pumps with the discharge valve closed.
D. Vent systems only after initiating system flow.
Start centrifugal pumps with the discharge valve throttled.
Which one of the following will result in a higher probability and/or severity of water hammer in a
flowing water system?
A. Gradual pipe bends rather than sharp pipe bends.
B. Shorter pipe lengths rather than longer pipe lengths.
C. Lower initial flow rates rather than higher initial flow rates.
D. Shorter valve stroke times rather than longer valve stroke times.
Shorter valve stroke times rather than longer valve stroke times.
An 85 gpm leak to atmosphere has developed from a cooling water system that is operating at 100
psig. Which one of the following will be the approximate leak rate when system pressure has
decreased to 50 psig?
A. 33 gpm
B. 41 gpm
C. 52 gpm
D. 60 gpm
60 gpm
Mass flow rate equals volumetric flow rate times…
A. specific volume.
B. density.
C. specific gravity.
D. velocity.
Density
A 55 gpm leak to atmosphere has developed from a cooling water system that is operating at 100 psig.
Which one of the following will be the approximate leak rate when system pressure has decreased to
50 psig?
A. 28 gpm
B. 32 gpm
C. 39 gpm
D. 45 gpm
39 gpm
A 75 gpm leak to atmosphere has developed from a cooling water system that is operating at 80 psig.
Which one of the following will be the approximate leak rate when system pressure has decreased to
40 psig?
A. 38 gpm
B. 44 gpm
C. 53 gpm
D. 59 gpm
53 gpm
A 60 gpm leak to atmosphere has developed from a cooling water system that is operating at 150 psig.
Which one of the following will be the approximate leak rate when system pressure has decreased to
75 psig?
A. 15 gpm
B. 30 gpm
C. 42 gpm
D. 53 gpm
42 gpm
A 100 gpm leak to atmosphere has developed from a cooling water system that is operating at 60 psig.
Which one of the following will be the approximate leak rate when system pressure has decreased to
20 psig?
A. 33 gpm
B. 53 gpm
C. 58 gpm
D. 71 gpm
58 gpm
A 100 gpm leak to atmosphere has developed from a cooling water system that is operating at 45 psig.
Which one of the following will be the approximate leak rate when system pressure has decreased to
30 psig?
A. 25 gpm
B. 50 gpm
C. 67 gpm
D. 82 gpm
82 gpm
A 47 gpm leak to atmosphere has developed from a cooling water system that is operating at 150 psig.
Which one of the following will be the approximate leak rate when system pressure has decreased to
75 psig?
A. 24 gpm
B. 33 gpm
C. 39 gpm
D. 46 gpm
33 gpm
An 80 gpm leak to atmosphere has developed from a cooling water system that is operating at 100
psig. Which one of the following will be the approximate leak rate when system pressure has
decreased to 75 psig?
A. 69 gpm
B. 60 gpm
C. 51 gpm
D. 40 gpm
69 gpm
A 60 gpm leak to atmosphere has developed from a cooling water system that is operating at 150 psig.
Which one of the following will be the approximate leak rate when system pressure has decreased to
100 psig?
A. 27 gpm
B. 35 gpm
C. 40 gpm
D. 49 gpm
49 gpm
An 80 gpm leak to atmosphere has developed from a cooling water system that is operating at 150
psig. Which one of the following will be the approximate leak rate when system pressure has
decreased to 75 psig?
A. 20 gpm
B. 40 gpm
C. 49 gpm
D. 57 gpm
57 gpm
An 80 gpm leak to atmosphere has developed from a cooling water system that is operating at 150
psig. Which one of the following will be the approximate leak rate when system pressure has
decreased to 100 psig?
A. 36 gpm
B. 53 gpm
C. 56 gpm
D. 65 gpm
65 gpm
A 75 gpm leak to atmosphere has developed from a cooling water system that is operating at 100 psig.
Which one of the following will be the approximate leak rate when system pressure has decreased to
80 psig?
A. 26 gpm
B. 39 gpm
C. 56 gpm
D. 67 gpm
67 gpm
Which one of the following describes the relationship between the main steam mass flow rate leaving
a steam generator and the main feedwater mass flow rate entering the same steam generator at
steady-state power operation? (Assume no other addition/removal of steam generator inventory.)
A. The mass flow rates will be the same only if downcomer level is constant.
B. The mass flow rates will be the same only if the reactor is operating near rated power.
C. The main steam mass flow rate is smaller than the main feedwater mass flow rate by the amount of
moisture removed by the steam generator moisture separators.
D. The main steam mass flow rate is greater than the main feedwater mass flow rate by the amount of
moisture removed by the steam generator moisture separators
The mass flow rates will be the same only if downcomer level is constant.