Enhancement of the regression rate in hybrid rocket motor utilizing high energetic additives

Abstract

The research on evaluating and improving the performance of hybrid rocket propulsion has been initiated. Since the Hybrid Rocket Motor's (HRM) deployment in the propulsion system is limited by its poor combustion efficiency and low regression rate. As a result, a thorough examination into the use of high-energy additives to improve the performance of the Hybrid Rocket Motor (HRM) in terms of regression rate and thrust is underway. Experimental studies are conducted to see the potential of High Energetic Additives as regression rate enhancer alongside with other different energetic additives. The parameters to be found in the experiment are the regression rate, thrust, and specific impulse. A lab-scale motor is developed to conduct the experimental studies. This is done by doping Boron, Aluminium and High Entropy Alloy (HEA) into the Paraffin-wax as a regression rate enhancer. Different composition of additives is prepared to find the optimum performance for the hybrid rocket. High entropy alloys are among the most advanced materials for high performance applications. Characterizations and thermal analysis of the solid fuel using x-ray diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive X-Ray Analysis (EDX), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) is carried out to determine the structure, thermal decomposition, particle distribution and energy characteristics of the solid fuel with the energetic additives. This is done to further study and identify the effect of elemental composition of the materials use as energetic additives. From the experimental study, the sample fuel doped with 5 wt% of boron had the highest regression rate, followed by 7 wt% of aluminium and 5 wt% of high entropy alloy, with regression rates of 1.45, 1.37, and 1.2, respectively. It is determined that High Entropy Alloy does enhance the hybrid rocket's performance in terms of regression rate.