Research On Measurement Of Combustion Flow Field By Tracer Particle Imaging Technology

Aircraft engine is an important area for technological competition.One of the biggest challenge in the aircraft engine manufacture is the structural design of the combustion chamber.The oxygen required for combustion in the combustion chamber originates from the air around the aircraft.The inhomogeneous flow of air leads to a complex combustion flow field.The actual combustion exhibits unsteady and unstable characteristics,moreover the temperature and velocity of flame are complicated and strongly coupled.Mastering the combustion field structure and energy transport is critical to the design of engine.Numerical simulation and experiment are two major methods to study the combustion phenomenon.Although numerical simulation technology has developed rapidly and can provide more detailed spatial and temporal information,the physical model of numerical simulation is still imcompleted.In addition,experimental method also plays a leading role in modeling and research of multi – physics coupling fields such as turbulence/chemical reaction interactions.Therefore,the research and development of aircraft combustion chambers still rely mainly on experiments.In this paper,the experiment is capable of obtaining velocity data of combustion field.After comprehensive analysis of data,the evolution process of the flame turbulent mixing layer,the flame structure and propagation process are obtained.In order to obtain deeper understanding of the flame mechanism,the jet flame experimental platform was built to enable supersonic and low speed flame combustion,which was used as a research platform for related research.The particle velocity measurementtechnique was used to measure the velocity distribution in the combustion flow,and the structure of combustion and the influencing factors of the experimental results were analyzed.Based on experimental data of flame velocity field,there are some conclusions drawn.The choice of frame rate can affect the image result.The larger laser energy can provide the more details about the position information of the particles in the flow field.The use of filter can greatly improve the signal-to-noise ratio of particles in the image.The choice of the interpretation will result from the flow field details and the velocity vector distribution.The flank combustion equivalence ratio will change the combustion modality and the flow rate will have more influence on the combustion velocity distribution.