Three-dimensional aerodynamic optimization for the two-stage axial-flow fan based on work distribution

By integrating genetic algorithm with response surface methodology,this paper developed an optimization system,with introduction of a quasi-three-dimensional through-flow design code and a blade formatting code.While a three-dimensional CFD (computational fluid dynamics) solver was involved,this paper established a numerical aerodynamic optimization platform for three-dimensional blades of axial-flow compressors.The optimization in this paper mainly has four features.First,it applies the conventional inverse design method instead of common CAGD (computer aided geometric design) parameterization method to generate a three-dimensional blade.Second,it chooses aerodynamic parameters with physical meaning as optimization design variables instead of purely geometrical parameters.Third,it presents a stage-by-stage optimization strategy about the multistage turbomachinery optimization.Fourth,it introduces the visual analysis method into optimization.The above techniques were applied,first,to a two-stage axial-flow fan for its maximum mass flow rate,and then,to the reformed two-stage axial-flow fan for its maximum adiabatic efficiency.The work distributions were taken as design variables,which were parametrically represented by means of Bézier curves.The two examples elucidate that not only the techniques mentioned above are appropriate and effective in engineering,but also the design guidance for similar inverse design problems can be obtained from the optimization results.