One-dimensional performance modelling of the ram accelerator in sub-detonative regime

A one-dimensional performance analysis code has been developed at the ”Laboratoire de Combustion et de D´etonique” to predict the thrust in the thermally choked ram accelerator propulsive mode. This research code incorporates the following equations of state: ideal gas, Boltzmann, Percus-Yevick, and Becker-Kistiakowsky-Wilson for both quasi-steady and unsteady flow situations. Experimental data from a representative ram accelerator experiment at the University of Washington 38-mm-bore facility were used for code validation. The predicted thrust and velocity agreed well with experimental measurements. Details about the algorithm for thrust calculations in the thermally choked ram accelerator propulsive mode under unsteady flow conditions while incorporating the influence of real gas behavior in the combustion process are presented.