Solid Rocket Motors Internal Ballistic Model With Erosive and Condensed Phase Considerations

Abstract

Solid rocket motors are used for propulsion units of both suborbital and orbital aerospace vehicles. Their main advantages are their simplicity, low cost and reliability. Due to attainable high thrust they have a wide application as boosters (as space shuttle boosters, Delta rocket boosters). They were also used as main stages, retrorocket units, stage separation control units, main propulsion units for suborbital vehicles. An interior ballistics model is implemented and applied for a double base and composite propellant boosters to be used for a boosted dart suborbital vehicle. Erosion and condensed phase are taken into account and numerical results are shown in comparison with experimental data obtained on test firings for each motor. The advantages of the implementation are that it offers a fast calculation of the main parameters of the solid rocket motor unit (thrust, burn time, specific impulse, total impulse). The solid fuel characteristics and the geometry of the motor are contained within two input files while the results of the calculations are presented to the user in a several output files. The motors are built using steel as a casing material and test firings are performed on a horizontal test bench.