The sensitivity analysis for APR1400 nodalization under Large Break LOCA condition based on mars code
The phenomena of loss of coolant accident have been investigated for long time and the result of experiment shows that the flow condition in the downcomer during the end-of-blowdown were highly multi-dimensional at full-scale. However, the downcomer nodalization of input deck for large b...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
VINCA Institute of Nuclear Sciences
2017-01-01
|
| Series: | Nuclear Technology and Radiation Protection |
| Subjects: | |
| Online Access: | http://www.doiserbia.nb.rs/img/doi/1451-3994/2017/1451-39941701010J.pdf |
| Summary: | The phenomena of loss of coolant accident have been investigated for long
time and the result of experiment shows that the flow condition in the
downcomer during the end-of-blowdown were highly multi-dimensional at
full-scale. However, the downcomer nodalization of input deck for large
break loss of coolant accident used in advanced power reactor 1400 analyses
are made up with 1-D model and improperly designed to describe realistic
coolant phenomena during loss of coolant accident analysis. In this paper,
the authors modified the nodalization of MARS code LBLOCA input deck and
performed LBLOCA analysis with new input deck. From original LBLOCA input
deck file, the nodalization of downcomer and junction connections with 4
cold legs and direct vessel injection lines are modified for reflecting the
realistic cross-flow effect and real downcomer structure. The analysis
results show that the peak cladding temperature of new input deck
decreases more rapidly than previous result and that the drop of peak
cladding temperature was advanced by application of momentum flux term in
cross-flow. Additionally, the authors developed a new input deck
with multi-dimensional downcomer model and ran MARS code with
multi-dimensional input deck as well. By using the modified input deck,
the Emergency core cooling system by-pass flow phenomena is better
characterized and found to be consistent with both experimental report and
regulatory guide. |
|---|---|
| ISSN: | 1451-3994 1452-8185 |