ツヨク カネツ サレル ドウシンニジュウエンカンナイ ガスリュウ ノ デンネツ ジュウドウ カイリョウガタ κ-ε モデル ニヨル スウチ カイセキ

A numerical analysis by use of the k-ε turbulence model was performed on the flow and heat transfer characteristics of the strongly heated annular gas flow. Some modifications were added to the Nagano & Hishida's original k-ε turbulence model, in order to improve the prediction efficiency in the low Reynolds number region. This modified version is superior to the original one in that it predicts the high flux heat transfer performance more accurately than the original one does. Calculated radial profiles of the turbulence energy and of the average streamwise velocity suggest that no definite laminarization occurs, even in the highest heat flux case. It is concluded, therefore, that the annular gas flows are less vulnerable to the laminarization than the circular tube flows