Exploration about compressor intermediate duct design

To improve the flow losses of compressor intermediate duct and ensure rapidity of the design process and accuracy of the results, first, an optimization algorithm combined with different aerodynamic evaluation methods is proposed for the design of compressor annular strutted intermediate duct. The fast two-dimensional evaluation method is used for global optimization, and the three-dimensional viscous evaluation method by solving Reynolds averaged Navier-Stokes (RANS) equation is used for local optimization. This combination is effective and efficient for the design process, and a parameterization method beneficial to flow area control is formulated. Second, a sample is designed and loss analysis is performed. It is proved that the duct design result will suffer great deviation if the strut effect is ignored. And a flow area raise in the middle of the duct has a positive effect on reducing the total loss. This raise of area reduces the strong pressure gradient and reaccelerates the flow at the rear of the duct. The best rate of area raise exists which is affected by the profile of the strut and the ratio of the inlet to outlet area. Good agreement with similar design approaches is achieved, and it proves that the design method used in this text is valid.