Experimental and Numerical Investigation of Hypervelocity Carbon Dioxide Flow over Blunt Bodies

This paper represents ongoing efforts to study high-enthalpy carbon dioxide flows in anticipation of the upcoming Science Laboratory and future missions. The work is motivated by observed anomalies between experimental numerical studies in hypervelocity impulse facilities. In this study, experiments are conducted in the expansion tube that, by virtue of its flow acceleration process, exhibits minimal freestream dissociation comparison with reflected shock tunnels, simplifying comparison with simulations. Shock shapes of the laboratory at angles of attack of 0, 11, and 16 deg and spherical geometries are in very good agreement with simulations detailed thermochemical modeling. Laboratory shock shapes at a 0 deg of attack are also in good with data from the LENS X expansion tunnel facility, confirming results are facility-independent for the type of flow acceleration. The shock standoff distance is sensitive to the thermochemical state and is used as an measurable for comparison with simulations and two different theoretical models. For low-density -scale experiments, it is seen that models based upon assumptions of large binary scaling values do not match the and numerical results. In an effort to address surface chemistry issues arising in high-enthalpy groundtest , spherical stagnation point and aeroshell heat transfer distributions are also compared with the . Heat transfer distributions over the aeroshell at the three angles of attack are in reasonable agreement simulations, and the data fall within the noncatalytic and supercatalytic solutions.