| Title |
Numerical Analysis of Turbulent Carbon Dioxide Flow and Heat Transfer under Supercritical State in a Straight Duct with a Square Cross-Section |
| Keywords |
Supercritical state ; 초임계상태 ; Carbon dioxide ; 이산화탄소 ; Turbulent heat transfer ; 난류 열전달 ; Square duct ; 정사각 덕트 |
| Abstract |
Turbulent carbon dioxide flows and cooling heat transfers under supercritical state in a straight duct with a square cross-section are numerically analyzed employing low Reynolds number model and algebraic stress model. The flow is assumed to be quasi- incompressible. Predicted Nusselt number and friction factor are compared with the experimental data, Blasius correlation for friction factor and Dittus-Boelter correlation for Nusselt number. Computational results for the Fanning's friction factor agree well with the all Rohsenow and Choi's correlation, Liou and Hwang's experimental data and Blasius correlation. The results obtained by algebraic stress model agree more with the Liou and Hwang's experimental data, while the results obtained by low Reynolds number model agree more with Blasius correlation.
In the computation of Nusselt number, Dittus-Boelter correlation can not exactly fit the computational results. Therefore we propose the new correlation for the turbulent cooling heat transfer of carbon dioxide under supercritical state. |