Density measurement and calculation of RP-3 aviation kerosene at sub- and supercritical condition

Considering the deficiency of the physical parameters for endothermic hydrocarbon fuel in the research of aerospace propulsion systems, a density measuring device with a gas driven piston was designed for the density measurement of RP-3 aviation kerosene. The density values of the kerosene in the temperature range from 293 K to 673 K and the pressure range from 1.2 MPa to 4 MPa were experimentally measured, and the density varying with temperature and pressure was analyzed. Besides, a method based on the Peng-Robinson equation of state was derived for density calculation of real fluid, and the calculation process was calibrated based on the existing density data of n-decane (C₁₀H₂₂). Finally, the computational density values of the RP-3 aviation kerosene were found to be slightly lower than the experimental results, especially in low-temperature and near-critical stage. It is mainly caused by the limitations of this computational method for calculating the density of mixtures.