Study of the form function and combustion characteristics of partially‐cut stick propellants

Abstract

To study the form function and combustion characteristics of partially‐cut stick propellants, this paper derived and established the form function of this complex geometry propellant and analyzed the influence of cutting parameters on the form function. The analysis showed that partially‐cut stick propellants retain the high progressive combustion of multi‐aperture granular propellant, which is proportional to the distance between the notch and inversely proportional to the width of the notch. Based on this, partially‐cut stick propellants with different notches were prepared, and closed vessel tests were conducted. The experimental results showed that the notch had a significant effect on the combustion characteristics of the propellant. When there were notches, the wider the notch, the faster the pressure rise. The pressure in the closed vessel for stick propellants without notches rose the fastest. The burning rate of non‐notched or narrow‐notched fluctuated, while the burning rate of wide‐notched was stable. The dynamic vivacity data showed that the wider the notch, the more stable the change of the burning surface, and the combustion characteristic was closer to the granular propellant. Based on the analysis of form function and combustion characteristics, it is recommended that the notch width be 1 mm and the distance between notches on the same side should be the length of a granular propellant for the double‐base homogeneous 19‐perforated propellant studied in this paper.