| This subject is supported by the National Natural Science Foundation (50976044)，mainly studied jet noise problem. Jet noise is a common aerodynamic noise problem,closely related to daily life. The study of the problem has great theoretical and practicalsignificance.Based on a summary of the existing jet noise theory as well as the relevantexperiences of building jet noise test platforms, the dissertation designed and built a highquality subsonic jet noise test platform. First The overall program are Demonstrated.Also, the technical parameters and the Collocation requirements are given too. Second,adopted to the design principles, the dissertation made a detailed analysis of differentmodules of the test platform，Combined the CFD assistive technology with the3Dmodeling technology,the design of nozzle are very innovative. Finally, the design of theSubsonic jet noise test platform are finished.After the completion of the test platform, the dissertation inspect the test platform intwo aspects:jet flow field experiments, jet noise field.Among them, the jet flowfield experiments to ensure the relevant parameters (Manumber, pressure, etc.) to meetthe design requirements of the test platform. Jet flow field results are consistent with theoretical calculations; And the result of the jet noise field experimental show that thespectrum characteristics of subsonic jet noise changes with the difference of Ma number.The experimental results above indicate that: the jet noise test platform can meet thedesign requirement, and can be used to undertake thefollow-up study of jet noise.In addition, two-dimensional and three-dimensional simulation of subsonic jet flowfield are discussed in the dissertation too. Through the acquisition of twodimensional simulation result,the axis cross speed of the flow field and the dimensionlessvelocity model combining prove that the CFD simulation is very practical in jetsimulationg. The three-dimensional jet simulation mainly study the impact of different m-eshing methods of the jet flow field. Finally, the dissertation provide a suitablethree-dimensional meshing methods.This dissertation carry out some research on the jet noise problem. These researchmainly focus on three aspects: theoretical analysis, experimental verification andnumerical simulation, providing a reference program for future similar testplatform construction. In addition, the jet noise experimental data and simulation calcula- tion results presented in this dissertation aslo have a certain value. |
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