Researchers : Hokyo Jung, Serin Yoon, Youngjae Kim in collaboration with SNUST, SNU & KNU
Motivation & Objectives
-For safety improvement of nuclear power plant, it is necessary to understand and estimate turbulent bubbly flows
-Previous models for bubble size has insufficient predictive capabilities
-Because of complex and nonlinear interaction between the bubble and turbulence
Background - ANN
-Advantages of artificial neural network (ANN) as a modeling method
- It can detect complex nonlinear relationships between parameters
: It is very flexible and effective for nonlinear problems
-It needs no pre-defined model, assumption and prior knowledge
: It is useful for modeling variables like 𝐷_𝑠𝑚 that has many parameters
-Process of using ANN to model 𝐷_𝑠𝑚/𝑅
Data-driven modeling
-Data-driven D_sm modeling in turbulent bubbly flows using ANN
-Modeling procedure
-Collect data from experiments or literatures
-Data-driven D_sm modeling in turbulent bubbly flows using ANN
RANS with ANN-based D_sm model
-Structure of data-driven RANS simulation using ANN-based model for 𝐷_𝑠𝑚
-Governing equations : An Eulerian-Eulerian method
-Validation results and comparison with previous studies
Errors from RANS with ANN-based model were significantly lower than previous models