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Axial flow compressor is one of the most important parts of gas turbine units. Therefore, its design and performance prediction are very important. One-dimensional modeling is a simple, fast and accurate method for performance prediction of any type of compressors with different geometries. In this approach, inlet flow conditions and compressor geometry are known and by considering various compressor losses, velocity triangles at rotor, and stator inlets and outlets are determined, and then compressor performance characteristics are predicted. Numerous models have been developed theoretically and experimentally for estimating various types of compressor losses. In present work, performance characteristics of the axial-flow compressor are predicted based on one-dimensional modeling approach. In this work, models of Lieblein, Koch-Smith, Herrig, Johnsen-Bullock, Pollard-Gostelow, Aungier, Hunter-Cumpsty Reneau are implemented to consider compressor losses, incidence angles, deviation angles, stall and surge conditions. The model results are compared with experimental data to validate the model. This model can be used for various types of single stage axial-flow compressors with different geometries, as well as multistage axial-flow compressors.

Recently a new inverse design algorithm has been developed for the design of ducts, called ball-spine (BS). In the BS algorithm, the duct walls are considered as a set of virtual balls that can freely move along some specified directions, called 'spines'. Initial geometry is guessed and the flow field is analyzed by a flow solver. Comparing the computed pressure distribution (CPD) with the target pressure distribution (TPD), new balls positions for the modified geometry are determined. This procedure is repeated until the target pressure is achieved. In the present work, the ball-spine algorithm is applied to three-dimensional design of axial compressor blades. The design procedure is tested on blades based on NACA65-410 and NACA65-610 profiles and the accuracy of the method is shown to be very good. As an application, the pressure distribution of the blade with NACA65-610 profiles is modified and the pressure gradient in the aft part of the blade is decreased and selected as target pressure distribution. The corresponding geometry which satisfies the target pressure is determined using the BS design algorithm.