A method to obtain the heat load on the internal wall of a rocket thrust chamber using an inverse problem approach is described. According to the ¤classical¥ approach, the heat load on the internal wall of the chamber is assumed as the product of a heat transfer coe©cient and the temperature di¨erence of adiabatic wall temperature and local wall surface temperature. The time-dependent temperature distribution of the external wall of the thruster chamber is used to obtain empirical curve ¦ttings to the temperature pro¦le of the near wall §ow ¦eld (adiabatic wall temperature) and the heat transfer coe©cient pro¦le. The applicability of the method is veri¦ed by applying it to three di¨erent problems; a model problem, an analytical solution, and a set of experimental data.

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This paper presents a solver for the CFD (computational fluid dynamics) modeling of catalytic chambers in monopropellant thrusters based on the open-source OpenFOAM® (Open Field Operation and Manipulation) framework. A model was formulated and used to simulate the physical and thermochemical processes taking place inside the catalytic chambers of the monopropellant thrusters. The code integrates reacting gas flow in porous media, with mass and heat transport. The most important implemented functionalities were the separation of two reactive gases, one transient reactive gas flowing between the catalyst bed interstices (interstitial gas), and another static reactive gas on the surface of catalyst particles, or pellets (surface gas). Homogeneous and heterogeneous reactions occur on the interstitial gas and the catalyst particle, respectively. A flexible definition of porous properties, a calculation of multicomponent diffusion-flux mass, a diffusion mass coeffcient, a mass transfer coeffcient, and a heat transfer coeffcient were implemented as well. Experimental and analytical studies about hydrazine monopropellant thrusters in the literature were used to the case tests and verification of the solver. Temperature and mass fraction fields were simulated and compared. The results of the temperature profile are in agreement with experimental and theoretical studies found in the literature, and mass fraction presents some differences.

This work presents the simulation of the internal flow in a swirl atomizer. The geometry of the atomizer is calculated by analytical equations used in engineering. The numerical simulation of the two-phase flow is performed by using two equations k-ε turbulence model. The fluids are presented as two-fluid homogeneous model. The interface between two phases is calculated by free surface model. The distribution fields of the axial and tangential velocities, pressures and air core are obtained. The aim of this work is to compare the results obtained by numerical simulation with ones obtained analytically. Also, to study the internal fluids flow inside the atomizer.