Experimental study on the pressure drop characteristics of supercritical CO₂ in horizontal rectangular microchannels

The pressure drop characteristics of supercritical carbon dioxide (S-CO 2 ) are experimentally studied in horizontal rectangular microchannels with hydraulic diameters 1 and mm, which used printed circuit heat exchangers. operating conditions include an 9–12 MPa, a mass flux 290–1200 kg/m s, 25–50 kW/m . four contributors to the S-CO were investigated. results indicate that total decreases for lower pressures fluxes, whereas has little impact. most significant contributor is frictional drop. accelerational increases flux. Eventually, new resistance correlation proposed where microchannel size thermophysical property variations considered.