Combustion Characteristics of Paraffin-Polyethylene Blends Fuel for Solid Fuel Ramjet

Abstract

In this paper, a series of firing tests have been conducted via a connected pipe facility to investigate the influences of the paraffin blends fuel on combustion characteristics of solid-fuel ramjet engines. A three-dimensional (3D) scanner and scanning electron microscope (SEM) have been used to obtain the local regression rate and the morphology of the solid fuel after combustion, respectively. The results indicate that decreasing the inlet diameter increases the performance of a solid fuel ramjet (SFRJ), and increasing the paraffin concentration and decreasing the port diameter of the solid fuel can enhance the average regression rate but have negative effects on the performance. The SEM results indicate that increasing paraffin concentration can lead to the reduction of the size and quantity of the carbon particles attached and agglomerated at the fuel surface and also has a significant effect on the morphology of the fuel surface, such as the roughness and the separation between paraffin and high-density polyethylene for blended fuel.