The Aerodynamic And Structural Design Of Subsonic Repeating Stages Compressor Testing Rig

Compressor is one of the three major parts of aero-engine core engine and combustion gas turbine, and for a long time, the development of its performances is limited by the accurate information of its internal flow field. At present, there are three major methods to study gas dynamics — theoretical analysis, numerical simulation and experimental research. Because of its authenticity and reliability, experimental research has an advantage in being inspection and guidance of the other two methods, and an irreplaceable role in the research of gas dynamics. Subsonic compressor testing rig is a relatively special one among many experimental appliance. Compared with cascade wind tunnel, it can simulate and measure the compressor flow field in actual operating condition more truly, and in the comparation with high-transonic compressor testing rig, it has advantages in the accuracy of measurement and the cost of experiment, so, in the field of experiment, it received extensive attention of the researchers.In reference to the parameters of existing compressor testing rig at home and abroad, as the key laboratory of Liaoning Province,the small gas turbine technical laboratory of Dalian Maritime University intended to build a subsonic compressor testing rig, in order to provide more detailed and accurate experimental data for the research of the three dimensional flow field of compressor. The purpose of the thesis is carrying on the preliminary aerodynamic design and structural design.Firstly, with the aid of NREC, the thesis completed the aerodynamic design. Due to the design target is a repeating stage compressor, the study selected the design method, which finished the design of the single stage compressors firstly, and then copy the single compressor that has better performances to its rear. During the design process, on the basis of the solvingof simple radial equilibrium equation, the rotor blade is designed as twisted blade by using equivalent twist method, and the stator blade is designed as the straight blade. The stator blade profile is designed basing on the velocity triangle of mean blade. After accomplished the design of three single stage compressors designed in three different chords(100mm/150mm/200mm), applied NUMECA software to the single stage compressors. The results of the 3-D numerical simulation show that two compressors that designed in larger chord perform better in both performance and flow field. Then, the numerical simulation of the double stages compressors have shown that the compressor designed in 150mm chord has a worse flow field that has a bad influence on the performance of itself. Besides, in order to measure the parameters in the flow field, the compressor designed in 200mm chord gets the nod at last.Secondly, according to the results of the numerical simulation of the chosen design in four off-design-speed conditions, the compressor performance curves are gotten. The performance curves indicate that the chosen compressor operates well in off-design condition, combining with 3-D flow field numerical simulation results of the design-speed condition, the compressor designed in this thesis is proved to be a compressor that meets the design requirements.Finally, the structure of the testing rig is designed. Generally speaking, the testing rig is installed horizontally. The gas flows in the compressor in the axial direction evenly, and flows out in the radial direction through the volute. The methods of the measurement of the flow field in the compressor and the measuring instrument and its arrangement are also designed reasonably, in order to meet the requirement of the measurement of the performance and flow field of the compressor.