Analysis of Flow and Heat Transfer Characteristics of Supercritical CO_2 in Circular Tube

Convection heat transfer of CO 2 at supercritical pressures in horizontal circular tube is studied numerically.The effect of heat flux,temperature of the wall,mass flux,and pressure on the heat transfer coefficient is investigated.The simulated data indicates that heat flux and temperature of the wall affect slightly the convection heat transfer of supercritical CO 2,and mass flux and pressure affect it significantly.With the increase of mass flux,heat transfer coefficient is improved distinctly.The operation pressure is closer to the critical pressure,the change of heat transfer coefficient near critical line is clearer,and the peak value is higher.