Optimization of ducted counter–rotating fan blades on the basis of solving a 3d inverse problem with the aim of improving fan gasdynamic characteristics

When developing counter-rotating fans for advanced aircraft engines with ducted blades (CRTF), it is very important to ensure high acoustic and aerodynamic characteristics. To provide investigations of aerodynamic and acoustic performance of the original version of an advanced counter-rotating CRTF1 fan model with  in the C-3A anechoic chamber (CIAM), its experimental and mathematical models were developed and 3D steady viscous flow and integral characteristics were calculated. The paper presents a comparison of data computed by “mixing plane” approximation and the experimental CRTF1 data. This comparison shall demonstrate the validity of designing the CRTF2A second version without taking unsteady interaction into consideration. These comparisons of computed and measured data give evidence of good agreement at . The degree of coincidence between the computed and experimental data at  is satisfactory – maximum error is <2%. This paper presents some results of gasdynamic and aeroacoustic optimization of the configuration of a ducted fan carbon composite blade on the basis of the solution of a 3D-inverse problem [3]. A distinctive feature of a carbon composite blade as compared with a solid titanium blade is thicker leading and trailing edges and increased maximum blade profile thickness.