We analyzed the hydrodynamics of the flow into an axis-symmetrical combustion chamber with a central bluff body. Using an axis-symmetrical turbulent flow model we determined the extent of the recirculation region behind the bluff body as well as the location and intensity of maximum kinetic energy as a function of the cone angle of the chamber wall. We showed that by shortening the convergent conical section of the chamber we obtain a compact recirculation with higher turbulence intensity, with positive influence on gas mixing. We used the software FLUENT 6.3 for the numerical simulation of the gas flow inside the combustion chamber. The simplified geometry of the two types of combustion chambers was built using the pre-processor GAMBIT 2.4. Two structured meshes were obtained for the domains of numerical analysis with approximately 170,000 cells each. For modelling the turbulence of the flow we used three different turbulence models which were implemented in FLUENT 6.3.