CHAPTER 12 - Propellants for Integral Rocket Ramjet Systems

Abstract

This chapter discusses propellants for integral rocket ramjet systems. An initial selection of the propellant components is feasible on the basis of the combustion heat values, which allow the assessment of their energetic quality. The value of components selected in this manner are later examined in the light of other selection criteria such as their cost, processability, usability in gas generator, combustion efficiency in combustor, and the signature. The combustion in the chamber of the ramjet of the decomposition products from hydrocarbon-fueled compositions and carbon compositions leads to the production of gaseous products, provided that high levels of combustion efficiency are obtained. A preliminary assessment of the increase in performance, which is obtained by switching from a composition without particles to a particle-laden composition, can be done by comparing relative heating values. The hydrocarbon-fueled compositions generate lower molecular weight hydrocarbon fragments that are burned later in the secondary combustion chamber. Consequently, these compositions exhibit characteristics of combustion similar to gaseous hydrocarbons. The criteria for selecting the type of composition take features of future missions other than theoretical energy into consideration.