Study On The Performance Of The Expansion Swirler Combustion Chamber

The combustion chamber is the core part of aeroengine.The head structure of the combustion chamber is one of the main factors affecting the stability of the combustion chamber.The swirler is the most commonly used in the design of the combustion chamber head to produce a central recirculation zone and stable flame.The swirler has an important influence on the fuel atomization characteristics,flow field inside the combustion chamber,emission,outlet temperature quality,and combustion efficiency.The expansion swirler is the leading structure in modern aeroengines.The optimization of the head structure of the combustion chamber provides a reference for further research on the central staged combustion chamber.In this paper,methods of numerical simulation and experiment are mainly used to study the central staged combustion chamber with expanded angle swirler.First,PIV（Particle Image Velocimetry）is used to verify the accuracy of the turbulence model.Secondly,GSV（Global Sizing Velocimetry）is used to determine nozzle atomization parameters such as atomization fineness and nozzle opening angle.Third,use numerical simulation to calculate the expansion swirler combustor.In the calculation,the turbulence model uses the experimentally verified Realizable k-ε model;the combustion model uses the probability density function model;the radiation model uses the heat flux P1 model;and the spray model uses Discrete term model;atomization parameters are given by experiments.The calculation method adopts the SIMPLE method to solve the pressure-velocity coupling,and the convection term adopts the second-order upwind style,which is solved by implicit separation.The research results show that the expansion angle of the main stage swirler in the head structure of the combustion chamber has a greater impact on the cold flow field.The greater the expansion angle of the main stage,the smaller the central recirculation zone is.The installation angle of the first and second stage of the pilot swirler has less influence on the central recirculation zone than the expansion angle of the main stage.When the installation angle of the first stage and second stage blades of the pilot swirler is 40° to 45°,50° to 55°,the fuel atomization and ignition effect are better.When the expansion angle of the main stage swirler is 15° to 20°,the flow field and outlet temperature quality of the combustion chamber are better.