This study uses 3D numerical simulation to reveal radial thermal stratification and heat transfer deterioration criteria in supercritical CO₂ natural circulation under horizontal heating, providing a basis for passive decay heat removal in gas-cooled fast reactors.
Mao, Luo · Lin, Xie · Ziwen, Su · Zhao, Fulong · You, Ersheng · 77100149 · Tian, Ruifeng
Applied Thermal Engineering 2026
Bu = 2 × 10⁻⁶ is the threshold for buoyancy effect on density stratification
Radial thermal stratification deepens for Fr < 30, diminishes for Fr ∈ [30,100], and is negligible for Fr > 100
SBO ∈ [1.73 × 10⁻⁴, 2.38 × 10⁻⁴] marks the onset of HTD; beyond 2.38 × 10⁻⁴, top-bottom temperature difference exceeds tenfold