How effectively does the index of hydrogen deficiency in carbohydrates used in potassium nitrate propellant affect enthalpy change and its performance?

Résumé : This work looks at the relationship between the index of hydrogen deficiency (IHD) and the enthalpy of combustion of "sugar propellant," as well as the performance of carbohydrates with similar IHD values. The study used eight different carbohydrate sources as fuels in the propellant, combined with potassium nitrate as an oxidizer in a 35:65 ratio. The IHD of the sugars ranged from 0 (polyols) to 2 (disaccharides). Different propellant mixtures (carbohydrate-KN) were tested using calorimeters and chemical analysis. The results support the hypothesis that IHD is associated with the enthalpy of combustion of sugar propellant, with polyol reactions showing the highest enthalpy change. Moreover, carbohydrates with a higher molar mass and an IHD of 2 exhibit better performance than those with an IHD of 1.