This paper summarizes the investigations on the combustion behavior of paran-based hybrid rocket fuels with gaseous oxygen (GOX) as oxidizer. Combined experimental activities have been done at the DLR Institute of Space Propulsion in Lampoldshausen and at the Space Propulsion Laboratory (SPLab) of Politecnico di Milano. Regression rate tests have been done in a 2D radial micro burner at the DLR and at the SPLab. Fuel samples have been characterized by viscosity measurements, tensile tests and dierential scanning calorimeter (DSC). Tensile tests shows signicant improvement in maximum stress and elongation when polymers in low concentration are added to the paran samples. The values of the liquid fuel viscosities dier signicantly between the fuels. This aects the droplet entrainment process during combustion and also the regression rates of the fuels. Entrainment and regression rate increase for decreasing fuel liquid layer viscosity. An exponential relation has been found between the liquid fuel layer viscosity and the regression rate, which can be used to predict the regression rate of new liquefying fuels by measuring their viscosity. Nomenclature G ox Oxidizer mass ux, kg/m 2 s h Melt layer thickness, ṁ m Mass ow, kg/s p Pressure, baṙ r Regression rate, m/ṡ γ Shear rate, 1/s µ Dynamic viscosity, kg/ms σ Surface tension, N/m Subscript ent Entrainment l
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.