The Development of Mathematical Model for Solving Internal Processes of Solid Rocket Motor

Abstract

This research was aimed to simulate the combustion process inside motor of solid fuel rocket. The fuel was a mixture of Potassium Nitrate (KNO₃) and Dextrose (C₆H₁₂O₆) in ratio of 65/35. The simulation was conducted with a computer by simulating cylindrical fuel bar, outer diameter 48 mm, inner diameter 15 mm, length 112 mm, nozzle throat diameter 10.4 mm. The simulation divided into two cases, closed end and open end.  Pressure change inside the motor was based on burning area while thrust force was subjected to changing pressure. Meanwhile, total impulse, and specific impulse rose with increasing nozzle expansion ratio.  The specific impulse was between 112 – 126 s. In conclusion, the result of simulation could be implemented in designing effective and reliable rocket motor.