Reactor Experiments

Reactor Experiments

Instructor: Prof. Kune Y. SuhT/A : Sang Hyuk Yoon

Saturday, June 14, 2003Composer : Team F

Contents•Members and Malfunction

•Nuclear Power Plant System

•Drop of All Control Rod in CBA

•Turbine Trip

•FW Pump

Members of Team F•Members of Team F

•Jeong, Won Chae Choi, Sang Gook

• Kim, Chan Soo

• Mun, Seung Hyeon

• Yoon, Ei Sung

• Lee, Yoon Jeong

Malfunction• A-1 Drop of All Control Rods in CBA

• Choi, Sang Gook & Lee, Yoon Jeong

• J-55 Turbind Trip

• Jeong, Won Chae & Yoon, Ei Sung

• L-67 FW Pump Trip

• Kim, Chan Soo & Mun Seung Hyeon

Power Plant System

Control Rod•Choi, Sang gook

•Lee, Yoon Jeong

Control Rod

Grid of the Grid of the Control RodControl Rod

Grid of the Grid of the Control RodControl Rod

GSSSGSSSGSSSGSSS

Control Rod

control element control element drive mechanismdrive mechanism

control element control element drive mechanismdrive mechanism CEACEACEACEA

Control Rod

•Methods to Control the Activity in Core•Dilusion by Chemical and Volume

Control System •Boric acid is dissloved •But the reaction is slow

•Using the Control Rods

Control Rod•Function

To control the reactivity of the core by quick p

utting and pulling out the control rod

To solve the weak points of CVCS dilusion me

thod

Control Rod•Composition

Totally 81 rods

• Shut Down group A,B

• Regulating Control group

• Part Strength Control group

Control Element Drive Mechanism

– Magnetic Forced Mechanism

Control Rod•Composition

Material of the toxic substance in rod

- B4C

Material of the cladding

- Ni-Cr-Fe 652

Control Rod•Control Rods Accidents 1. Ejection of the control rods

Disorder of rod control equipmentMistake of operator

Disorder of rod control equipmentMistake of operator

Reactivity of the core increasesReactivity of the core increases

Generation of Serious peak power Generation of Serious peak power

Fuel damage, TripFuel damage, Trip

Control Rod•Control Rod accident

2. Drop of all control rods in CBA

Breaken equipmentInterception of electricity

Breaken equipmentInterception of electricity

Reactivity decreasesReactivity decreases

Power generation decreases Power generation decreases

Pressure, Temperature, DNBR changesPressure, Temperature, DNBR changes

Control Rod

0 500 1000 1500 2000-0.0040

-0.0035

-0.0030

-0.0025

-0.0020

-0.0015

-0.0010

-0.0005

0.0000

0.0005R

ea

ctivity

sec

Net reactivity

Control Rod

0 500 1000 1500 2000

292

294

296

298

300

302

304

306

308T

EM

P

sec

Average temperature of Primary loop

Control Rod

0 500 1000 1500 2000

278

280

282

284

286

288

290

292T

em

pe

ratu

re

sec

Core coolant temperature

Control Rod

0 500 1000 1500 200013800000

14000000

14200000

14400000

14600000

14800000

15000000

15200000

15400000

15600000

15800000p

ressu

re

sec

Pressurizer pressure

Control Rod

0 500 1000 1500 2000

5.2x106

5.4x106

5.6x106

5.8x106

6.0x106

6.2x106

6.4x106

Pre

ssu

re

sec

Steam generator Pressure

Control Rod

0 500 1000 1500 20001.2

1.4

1.6

1.8

2.0

2.2

2.4D

NB

R

SEC

DNBR

Control Rod• Conclusion

• Drop of all control rods in CBA

• Output of whole core power decreases

• average temperature decreases• reactivity increases(feedback effect)

• the reason of reactivity, DNBR movement

• According time goes, temperature and pressure decrease. The accident stops.

Turbine•Jeong, Won Chae

•Yoon, Ei Sung

Turbine•Function

To convert the steam which is made in the steam generator to energy

When the steam expands through the nozzle and blades of a turbine to a condenser, it rotates the rotor of the turbine blades, which links to the axis of the generator

Turbine

Scene of Turbine Building inside

Turbine

Scene of Turbine Building inside

Turbine

Turbine

Turbine

The system of the LP TurbineThe system of the LP Turbine

Turbine

The system of the HP TurbineThe system of the HP Turbine

Turbine• Causes of Turbine Trip

1. Overload (Overspeed)

2. Wearing the bearing

3. Solenoid trip

4. Low pressure of condenser

5. The manual trip of turbine

Turbine•Effects of the Turbine Trip

Turbine TripTurbine Trip

Steam dumped by ETSSteam dumped by ETS

Pressure reductionPressure reduction

The boiling point of the feed water is decreasedThe boiling point of the feed water is decreased

The heat removed through the steam generator is decreased

The heat removed through the steam generator is decreased

Turbine•Effects of the Turbine Trip

The temperature of reactor coolant increaseThe temperature of reactor coolant increase

The reactivity of core decrease

The sweeling of the water levelin the Reactor

The reactivity of core decrease

The sweeling of the water levelin the Reactor

Melting down of core <<Serious Accident!!!>>Melting down of core <<Serious Accident!!!>>

DNBDNB

Turbine•ETS (Emergecy Trip System)

Interrupting the supply of steam and discharging it if turbine is tripped

Functioning in mechanical or by the electrical signal from the detector

Turbine•Anticipation

PrimaryLoop

Secondary Loop

Temperature Increase Decrease

Pressure Increase Decrease

Turbine•Results

Reaction forSAFE

Reaction forSAFE

Turbine TripTurbine Trip

Temp. & Press. Incease in Steam LineTemp. & Press. Incease in Steam Line

Turbine Load = 0Turbine Load = 0

• Heat Exchange Rate Dec.• Water Level Dec.• Pressure Inc.

• Heat Exchange Rate Dec.• Water Level Dec.• Pressure Inc.

S/GS/G

Heat Transf.Rate Inc.

Heat Transf.Rate Inc.

2nd Loop Flow Rate Dec.

2nd Loop Flow Rate Dec.

Feed WaterTemp. Dec.Feed WaterTemp. Dec.

Turbine•Results

Turbine TripTurbine Trip Turbine Load = 0Turbine Load = 0

Turbine•Results

Turbine TripTurbine Trip 2nd Loop Flow Rate Dec.

2nd Loop Flow Rate Dec.

Turbine•Results

• Heat Exchange Rate Dec.• Water Level Dec.• Pressure Inc.

• Heat Exchange Rate Dec.• Water Level Dec.• Pressure Inc.

S/GS/G

2nd Loop Flow Rate Dec.

2nd Loop Flow Rate Dec.

Feed WaterTemp. Dec.Feed WaterTemp. Dec.

S/G Level S/G Prssure

Temp. of FW

Turbine•Results

Temp. & Press. Incease in Steam LineTemp. & Press. Incease in Steam Line• Heat Exchange Rate Dec.• Water Level Dec.• Pressure Inc.

• Heat Exchange Rate Dec.• Water Level Dec.• Pressure Inc.

S/GS/G

Steam Presssure from S/G

Turbine•Results

Turbine TripTurbine Trip

• Heat Exchange • Rate Dec.• Water Level Dec.• Pressure Inc.

• Heat Exchange • Rate Dec.• Water Level Dec.• Pressure Inc.

S/GS/G

2nd Loop Flow Rate Dec.

2nd Loop Flow Rate Dec.

Cold Leg Temp. Inc.Cold Leg Temp. Inc.

Reactivity Dec.Reactivity Dec.

Avg. Temp. Dec.Avg. Temp. Dec.

Hot Leg Temp. Dec.Hot Leg Temp. Dec.

Power Dec.Power Dec.DNBR > 1.3DNBR > 1.3

SAFESAFE

Turbine•Results

•Heat Exchange •Rate Dec.•Water Level Dec.•Pressure Inc.

•Heat Exchange •Rate Dec.•Water Level Dec.•Pressure Inc.

S/GS/G Cold Leg Temp. Inc.Cold Leg Temp. Inc.

Reactivity Dec.Reactivity Dec.

Cold Leg Temp. Reactivity

Turbine•Results

Reactivity Dec.Reactivity Dec.

Power Dec.Power Dec.DNBR > 1.3DNBR > 1.3

SAFESAFE

Relative Power DNBR

Turbine•Results

Avg. Temp. Dec.Avg. Temp. Dec.

Hot Leg Temp. Dec.Hot Leg Temp. Dec.

Power Dec.Power Dec.

Hot Leg Temp. Avg. Temp. of Core

Feedwater Pump•Kim, Chan Soo

•Mun, Seung Hyeon

Feedwater Pump• Function

Main feedwater system sends water to each steam generator(SG) Main feedwater pump circulates secondary water

Feedwater Pump

Feedwater Pump

Feedwater Pump

Feedwater Pump• Scram of Indiviual Main Feedwater Pump

1. Lubricating Oil Low Pressure(0.62kg/cm2)

2. Turbine Overspeed(~4928RPM)

3. Condenser Low Vacuum Level(480.6mmHg)

4. Impellent Force Bearing Excess Abrasion

5. Low Inspiration Pressure(Lo-NPSH)(15.5kg/cm2)

Feedwater Pump• Emegency Stop of All Main FW Pump

1. Safety Injection Signal

2. SG High Level

3. All condenser Pump Trip

4. Pump Release Header High Pressure

Feedwater Pump• Identification of event and causes

The loss of normal flow(LFW) event may be initiated by losing main feedwater pumps

Feedwater Pump• Sequence of event and system Operation

Decreasing water level and increasing pressure and temperature in the steam generator

Decreasing water level and increasing pressure and temperature in the steam generator

The RCS pressure and temperature rise.The RCS pressure and temperature rise.

Reactor tripReactor trip

Feedwater Pump• Emergency Measure of the Accident

Termination of main steam flowTermination of main steam flow

SG and Reactor Coolant System(RCS) pressurizationSG and Reactor Coolant System(RCS) pressurization

Decrease in core heat rateDecrease in core heat rate

Feedwater Pump

RCS becomes New Steady-state ConditionRCS becomes New Steady-state Condition

Auxiliary feedwater InjectionAuxiliary feedwater Injection

Cooldown by OperatorCooldown by Operator

Feedwater Pump• Analysis of Effects and Consequences

Maximum RCS pressure and fuel integraty for the LFW is less than that for the loss of condenser vacuum event(LOCV)

The initial Departure from nucleate boiling rate (DNBR) is the minimum DNBR

The minimum DNBR remains above 1.30.

Feedwater Pump• Conclusion

The RCS pressure remains below 19.5MPa and the SG pressure remains below 9.6MPa Thus, ensuring fuel cladding and secondary system integraty

[Assumtion] The only one pump would die.

Feedwater Pump

-200 0 200 400 600 800 1000 1200 1400 16006250000

6260000

6270000

6280000

6290000

6300000

6310000

6320000

S/G

pre

ssu

re#

1[P

a]

Time[sec] L67_1

D

S/G Generator #1

Feedwater Pump

-200 0 200 400 600 800 1000 1200 1400 16006250000

6260000

6270000

6280000

6290000

6300000

6310000

6320000

S/G

pre

ssu

re#

2 [P

a]

Time[sec] L67_1

E

S/G Generator #2

Feedwater Pump

-200 0 200 400 600 800 1000 1200 1400 16006250000

6260000

6270000

6280000

6290000

6300000

6310000

6320000

S/G

pre

ssu

re#

3[P

a]

Time[sec] L67_1

F

S/G Generator #3

Feedwater Pump

-200 0 200 400 600 800 1000 1200 1400 1600

307.55

307.60

307.65

307.70

307.75

307.80

307.85

307.90

307.95

Ave

rag

e te

mp

#1

[C]

Time[sec] L67_1

M

Average Temp. #1

Feedwater Pump

-200 0 200 400 600 800 1000 1200 1400 1600

307.55

307.60

307.65

307.70

307.75

307.80

307.85

307.90

307.95

Ave

rag

e te

mp

#2

[C]

Time[sec] L67_1

N

Average Temp. #2

Feedwater Pump

-200 0 200 400 600 800 1000 1200 1400 1600

-0.5

0.0

0.5

1.0

1.5

S/G

leve

l err

or

sig

na

l

Time[sec] L67_1

AA

S/G Level Error Signal

Feedwater Pump

-200 0 200 400 600 800 1000 1200 1400 1600

1.335

1.340

1.345

1.350

1.355

DN

BR

Time[sec] L67_1

AE

DNBR