Validação de simuladores de balística interna de motores-foguete a base de propelente sólido KNSU

Abstract

Solid propulsion, particularly involving potassium nitrate and sucrose (KNSU) based propellants, plays a fundamental role in academic aerospace development due to its accessibility and safety. However, the accuracy of performance predictions for academic rocket motors still faces challenges associated with combustion modeling and the effects of condensed species. This study aimed to validate the internal ballistics simulators Meteor and Empuxo 1.9 by comparing their theoretical predictions with experimental data obtained from static fire tests of the Netuno-F-Beta rocket motor. The methodology involved utilizing static test data, which included the acquisition of thrust curves and other parameters such as impulse and specific impulse, followed by computational simulations considering the distinct mathematical modeling of each software. The comparative analysis highlighted significant divergences between the models and reality: the Meteor simulator tended to overestimate thrust, total impulse, and specific impulse by at least 40% compared to experimental data, though it showed a maximum divergence of only 7% in burn time values. Conversely, Empuxo 1.9 underestimated maximum thrust (59%) and overestimated burn time (83%), but yielded total impulse and specific impulse values closer to the experimental results, with absolute relative differences of at most 17% and 30%, respectively. It is concluded that while both software programs are useful tools for rocket motor design, the observed discrepancies indicate limitations in the simulations, highlighting the need for refinement in input parameters and mathematical modeling to increase the fidelity of the results.