| Turbine fan engine is the main jet thruster of today's aircraft. With the development of engine design technology and aircraft requirement, the design of fan is going to the target of higher pressure-radio, efficiency, stably working scope as a vital portion in compressor design. Forward swept can improve the shock wave structure, by weakening the shock wave, reducing the shock wave loss, it improves the aerodynamic performance of rotor. In this paper, linear forward swept is used for the design of a mid-size axial fan. It is indicated during the investigation work that forward swept will affect the aerodynamic performance of compressor blade.A general midsize axial fan was designed according to the cooperator, with performance goal of pressure-radio 1.8, adiabatic efficiency 0.86, stably working scope 15%. In the paper, the rotor performance goal was fixed on pressure-radio: 1.9, adiabatic efficiency: 0.9, stably working scope:15% based on the diffuser design technology. In order to meet the performance target, appropriate blade midline, blade thickness distribution and forward swept was used for the fan design because of the unchangeable given size, rotate speed, and inlet condition of fan. Numerical simulation was done on five different rotor with forward swept angle of 0°,0.5°,2°,5°,8°degree. From the numerical simulation results, it was studied how forward swept affect the aerodynamic performance of compressor blade. Results indicated that forward swept influence the shock wave structure, improve the pressure-radio, adiabatic efficiency and stably working scope. Numerical simulation indicated that the pressure ratio of the 2 degree forward swept rotor was 2.065, efficiency was 0.9285 and surge margin was 15.8%. These performance parameters are all achieve and exceed the design target. A program of axial fan design and grid automatic creation was developed, and established the foundation for the further studies.The technology of micro turbine engine has developed rapidly during the recent 10 years. Considerable thrust-mass radio is its outstanding merit, but high fuel consumption is its demerit. Using the micro turbine fan can reduce its fuel consumption effectively. Consequently, on the foundation of the designed general size forward swept fan, this paper made the rotor dwindle in size using the law with the same flange velocity to the size with 73mm diameter and 115000r/min rotate speed. Comparing with the flow performance, this paper analyzed the influence of micromation on the rotor's aerodynamic performance. After micromation, obvious flow viscosity turned up, passage blocking become serious, the intensity of the shock waves in the passage got strong and loading distribution condition on the blade surface broke down. Basing on the particularity of micromation, the last part of this paper reduced the number of shrunken blade to 24 and analyzed the influence of the solidity which indicated the ideas that after reducing the blade number, passing ability strengthened, loading distribution condition on the blade surface was improved and pressure ratio and efficiency of the blade ascended.
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