Measurements and modeling of the density of rocket propellant RP-2 at temperatures to 573 K and pressures to 100 MPa

Liquid rocket propellants are subject to wide ranges of temperature and pressure when flowing through high performance liquid rocket engines. For example, as rocket propellant (RP) is used for regenerative cooling, near-wall fluid temperatures can exceed 700 K. The pressure can reach as high as 100 MPa when exiting the fuel pump. Therefore, accurate thermophysical property data, particularly density, are needed to accurately model the flow in rocket engines using computational fluid dynamics (CFD) and other engineering design tools. In this work, we report the density of two RP-2 samples at temperatures to 573 K and pressures to 100 MPa. A high-temperature, high-pressure (HTHP) variable-volume, windowed densimeter is used to determine the density. The experimental density data are satisfactorily correlated by the modified Tait equation that provides a means for interpolating the density within the experimental conditions investigated in this study. The HTHP perturbed-chain statistical associating fluid theory (PC-SAFT), Peng-Robinson (PR), and HTHP volume-translated PR equations of state are used to model RP-2 density over the entire temperature and pressure ranges.