[2C01-06] Development of Evaluation Methods, Safety Requirements for New NPPs

[2C01] Enhancement of Analysis Method for Important Phenomena of Severe Accidents at Reprocessing Plant

(H-5)Verification of Prediction Capability for Flame Model by Using the Burning Velocity Model and the Detonation Model in Full-Scale Facility

*Ichiro Nakamori¹, Takayuki Tomizuka¹, Atsuo Takahashi¹, Fumitomo Onishi¹, Takashi Kodama², Yoshikazu Tamauchi², Naoya Sato², Nobuyuki Tsuboi⁴, Koichi A. Hayashi³ (1. Advancesoft Corporation, 2. Japan Nuclear Fuel Limited, 3. COSMO SILVA Inc., 4. Kyushu Institute of Technology)

Keywords:FOCUS-i, 3D compressible fluid analysis, DDT, Detonation, wrinkling model, hydrogen explosions

For DDT analysis on a large length scale, it is necessary to reproduce the acceleration of the flame before the transition occurs. It is also desirable that such a simulation be possible even if we use the coarse grid resolution, to perform the computation in allowable time. One possibility is to reproduce the DDT while bypassing the detailed mechanism of detonation by using the DDT model based on the ignition delay time database. Another one is to achieve this by using a wrinkling model, which is less dependent on grid resolution, with the aim of reproducing the acceleration of the flame. We showed that the wrinkling model with RANS model along with the DDT model can reproduce the DDT computation.