2-D Transient Numerical Code for Hybrid Rocket Simulations with Detailed Chemistry Alexandre Mangeot 1 PRISME Laboratory, 63 avenue de Lattre de Tassigny, 18000 Bourges, France CNES, Rond Point de l'Espace, 91023 Evry Cedex, France Nicolas Gascoin 2 , Philippe Gillard 3 PRISME Laboratory, 63 avenue de Lattre de Tassigny, 18000 Bourges, France Hybrid rocket technology is known since the 30's and it is covered by a large number of experimental, fundamental and applied research works. It still suffers from a lack of chemical description and of detailed numerical simulation of core phenomena. Several numerical codes have emerged to simulate hybrid rocket combustion chamber but with limited consideration for detailed chemistry. They generally use global Arrhenius law or tabulated regression rate to simulate the solid fuel pyrolysis and equilibrium calculation for the combustion. A new 2-D transient reactive numerical code is proposed in this paper with the use of detailed chemical mechanisms for both pyrolysis and combustion reactions (over 1000 species and 10000 reactions). The features of the numerical code are presented in this paper, as well as the equations used to model the physical and chemical phenomena. The simplification assumptions are presented and the code validation is proposed through analytical and numerical comparisons with bibliographic data on reference test cases. The heat transfer in solid phase has been validated with a 99,9% accuracy. The mass and heat transfer in the gas phase have shown a mass and energy conservation of around 99,7%. The gas flow has been validated also on the boundary layer with more than 99,5% accuracy. For chemistry phenomena, special treatment must be applied, leading to an error less than 2% on the ignition delay for combustion process. Nomenclature = Activation energy Arrhenius factor of the k th reaction [J.mol -1 ] , = Body forces along the x and y directions [m.s -2 ] = Density [kg.m -3 ] = Dynamic viscosity [Pa.s] , = Heat fluxes along x and y directions [W.m -2 ] = Internal specific energy [J.kg -1 ] , = Mass fraction fluxes of the i th specie along the x and y directions [m.s -1 ] = Mass fraction of the i th specie = Mixture diffusion coefficient of the i th specie [m 2 .s -1 ] = Molar weight of the i th specie [kg.mol -1 ] = Net power thermal density [W.m -3 ] = Net production rate [kg.m -3 .s -1 ] = Perfect gas constant [J.mol -1 .K -1 ] 1 Main author: Alexandre.Mangeot@bourges.univ-orleans.fr , PhD Student 2 Corresponding author: Nicolas.Gascoin@bourges.univ-orleans.fr, Associate Professor, AIAA Member 3 Full Professor