Fuel Regression Characteristics of Axial-Injection End-Burning Hybrid Rocket Using Nitrous Oxide

Abstract

This study is an investigation of fuel regression characteristics in an axial-injection endburning hybrid rocket using nitrous oxide. Experiments were conducted using ϕ 38 mm cylindrical fuel grains with an array of 0.8 mm ports made from curable. Previous studies of end-burning hybrid rockets used gaseous oxygen as the oxidizer. Nitrous oxide may be more suitable than the gaseous oxygen for use in space-based missions because of the weight savings associated with the oxidizer storage vessels, supply system, and motor mass. In this study, two types of nozzle closures were employed to increase the initial chamber pressure and promote

Performance of Additively Manufactured Fuels for Hybrid Rockets

“…Okuda et al [67] burned fuel grains containing 80-90% acrylic acid ester, 5% hexamethylene acrylate, and a photopolymerization initiator with nitrous oxide instead of GOX. A nozzle closure and a melting nozzle were used to increase the initial chamber pressure and promote the formation of stabilized combustion.…”

“…Burning the UV-based fuel with nitrous oxide also resulted in a skewed burning surface as opposed to a flat burning surface when fired with GOX, as shown in Figure 29. Okuda et al [67] burned fuel grains containing 80-90% acrylic acid ester, 5% hexa methylene acrylate, and a photopolymerization initiator with nitrous oxide instead o GOX. A nozzle closure and a melting nozzle were used to increase the initial chambe pressure and promote the formation of stabilized combustion.…”

“…Burning the UV-based fuel with nitrous oxide also resulted in a skewed burn ing surface as opposed to a flat burning surface when fired with GOX, as shown in Figure 29. [67] and (b) GOX [62]. Images reprinted from Refs.…”

“…The chemical formula, heat of formation, and density of all chemicals are required to perform CEA calculations. The density and heat of formation for all the fuels considered here were sourced from the literature [17,67,[74][75][76][77][78]. However, the methods presented in the literature to estimate or measure the heats of formation of the fuels varied drastically.…”

“…In particular, the heats of formation of the polymeric fuels were computed from the definition of the stoichiometric heat of combustion which was directly estimated from a group additive method [80]. The one exception was for the representative UV-curable fuel which could not be computed due to a lack of information regarding its composition, so an experimental value provided by Okuda et al [67] was implemented instead. The density values provided in the literature were consistent and were therefore retained here.…”