Numerical Simulation For Combustion Flowfield Of Trapped Vortex Combustor At Low Speed

In recent several decades, trapped vortex combustor (TVC) has been used in many fields because ofbetter combustion flow characteristic and low emission performance. But there are also some problemsneed to be researched. And a further study should be done in present work.Firstly, the turbulent flow combustion model for TVC has been confirmed by detailed compare. Thelaw of performance about traditional TVC on different fractional combustion has been researched by usingof ANSYS FLUENT14.0. It shows that the length of flame of traditional TVC is long and temperature nearwall is high on high flow condition. For solve these problems, two-cavity combustor was designed in thispaper and the compare between it and traditional TVC on combustion performance has been done. Resultsshow that two-cavity combustor has obvious superiority on combustion efficiency. And because of the coldair in second cavity, high temperature zone is in the middle of cavity, so the wall can’t be burning-out.Then, a new structure named revolving-vortex-combustor (RVC) was put forward in this paper. Itcombines the traditional diffusive combustion technology and TVC principle, set a swirler before cavityand makes a3D revolving fuel stream. This fuel stream could mix with the flow of cavity and has a betterheat and mass transfer performance. Then it can ignite the fuel quickly and improve the combustionperformance. The compare between traditional TVC and RVC show that: the vortex of cold flow field ofRVC is steadier than TVC and the mixture of fuel and air is better. On combustion performance, theefficiency, length of flame and OTDF of RVC is better than traditional TVC. But pressure loss of RVC islittle high.Through this research, the effect law of staged combustion and the methods of shorting flame length,improving temperature of combustor wall and OTDF were obtained in present work. And a new structurenamed revolving-vortex-combustor (RVC) was put forward. These works can be used for trapped vortexcombustor engineering applications.