1. 2017 FRAPCON AND FRAPTRAN USER GROUP MEETNG
THE comparison between FRAPTRAN-2.0 and FRAPTRAN-1.5 on a station blackout analysis
Shang-yu Li1, Wan-Yun LI1, Jong-Rong WANG1, HAO-TZU LIN2, Shao-Wen CHEN1, CHUNKUAN SHIH1
After the FRAPTRAN 2.0 release , we did the study to compare the 2.0 and 1.5, in this study we chose the spent fuel pool in Station Blackout case, I will introduce the study flow chart, and introduce the FRAPTRAN model of the Spent fuel pool ,finally is CONCLUSION
Speaker:Shang-yu Li
1 Institute of Nuclear Engineering and Science, NTHU, Taiwan
2 Institute of Nuclear Energy Research, Taiwan

2. Outline CONCLUSION Introduction Model description
Analysis Flow Chart
TRACE Model
FRAPTRAN Model
RESULT AND DISCUSSION
CONCLUSION
Let’s start with my outline, first, I’ll Introduce the study, and the Model description, then illustrate the analysis conditions, finally present the result and make conclusion

3. Introduction
After Fukushima event, the safety analysis of the SFP for Chinshan NPP was performed by using TRACE and FRAPTRAN during the station blackout.
In this study, we used FRAPTRAN-1.5 and FRAPTRAN-2.0 to simulate the blackout analysis case, and to compare two version.

4. Model description

5. Model description Flow chart
First , finish the trace analysis ,then we have the Power history, Coolant conditions history, Cladding surface heat transfer coefficients history. And take those result as the boundary conditions in FRAPTRAN, besides, FRAPTRAN deck needs to input the fuel rod condition by user. After the FRAPTRAN analysis, the results are shown as follow.

6. Model description The TRACE model of the Spent fuel pool
Spent fuel pool size：
12.17 m × 7.87 m × m
Initial condition：
60 C / × 105 Pa
This is The TRACE model of the Spent fuel pool , the figure shows the fire water injection location of Spent fuel pool in TRACE model .

7. Model description The Fuel rod model of FRAPTRAN
This is Fuel rod model of FRAPTRAN. The axial fuel length from bottom to top was divided into 23 nodes, and the table shows the detail of fuel rod parameter.

8. RESULTs AND DISCUSSION

9. cladding inside temperature
FRAPTRAN-1.5
FRAPTRAN-2.0

10. cladding hoop strain FRAPTRAN-1.5 FRAPTRAN-2.0
In the cladding ballooning model, once the instability strain is reached in one node, no further strain is calculated for any nodes.
From the result, when the ballooning was happened at node 22, the another nodes were dropped to zero.

11. cladding hoop stress
FRAPTRAN-1.5
FRAPTRAN-2.0

12. structural radial gap
FRAPTRAN-1.5
FRAPTRAN-2.0

13. CONCLUSION
In the results of FRAPTRAN-2.0, the cladding temperature increase slowly than the results of FRAPTRAN-1.5 on node 22 and 23, so the cladding rupture time is almost the same as FRAPTRAN-1.5 result.
The results of FRAPTRAN-2.0 wouldn’t be calculate after the cladding failed and drop to zero.
FRAPTRAN1.5中，當程式計算到護套損壞後，程式就會停止計算
FRAPTRAN2.0中，當程式計算到護套損壞後，所有參數會下降至0

14. Thank you of your attention.