Numerical simulation study of hydrogen/air flame propagation and detonation characteristics in an annular cross section of gas turbine combustion chamber

Abstract

The trends and future directions of hydrogen safety research cannot be separated from the thermodynamic behavior of combustion and explosion, hydrogen spontaneous combustion, flame propagation behavior, thermodynamic mechanisms, and other related topics. In this paper, through the method of numerical simulation, considering the hydrogen flame propagation and detonation characteristics in the annular section of the combustion chamber commonly used in gas turbines, the form of detonation and detonation impact in the channel are evaluated. By discussing the deflagration to detonation transition of hydrogen/air premixed gas and premixed gas under different working conditions, it is found that the flame in the annular channel propagates close to the inner wall and forms a strong expansion and turbulence between the outer wall and the outer wall of the flame. The flame surface and the airflow shear accelerate the detonation of hydrogen. The area close to the wall on the outer side of the flame surface and the tip of the flame surface are prone to set off detonation. The high-pressure area after the detonation mainly acts on the symmetrical end face of the outer wall surface and ignition area. There is a critical working temperature to make the impact strength strongest when the detonation occurs. Reducing the equivalence ratio of the filling gas can significantly reduce the reaction speed and weaken the impact strength of the wall. When the equivalence ratio is less than a certain value, the filling gas is completely consumed in the form of deflagration.