Study on Influence of Evaporation Tube Flow Distribution on Combustion Characteristics of Micro Combustion Chamber

The combustion chamber is a critical component of turbojet engines, and airflow distribution plays an essential role in ensuring flame stability and optimizing combustion efficiency. This study investigates a miniature annular combustion chamber by employing SolidWorks 2022 software to model an evaporative tube combustion chamber. A dedicated combustion test platform was constructed for the proposed miniature combustion chamber. By adjusting the air and fuel flow ratios entering the evaporative tube, the temperature at the flame tube outlet was measured, and the combustion efficiency was subsequently calculated. In addition, numerical analysis was conducted using ANSYS/CFX software to simulate the flow field in the combustion chamber. The following conclusions were drawn from an analysis of the variations in the flow field and temperature field during the simulation process: When the flow rates in the ignition and dilution zones of the miniature annular combustion chamber remained constant, modifying the air-fuel flow ratio within the evaporative tube significantly enhanced the combustion characteristics within the chamber. Specifically, the combustion efficiency is closely related to the ratio of the air mass flow rate to the fuel mass flow rate within the evaporation tube. The highest combustion efficiency was achieved when the ratio fell within the range of 4.20 to 4.96. Furthermore, the area-averaged velocity at the combustion chamber outlet was independent of the air-fuel flow ratio but exhibited a positive correlation with the fuel flow entering the combustion chamber.