Design And Associated Issues Of A Three-stage Highly-loaded Low-reaction Boundary-layer-suction Compressor

Proposal of the concept of “low-reaction compressor” is an effective way toovercome the difficulty in the design of the highly-loaded compressor. Under theguarantee of higher efficiency of the rotor and boundary layer suction only appliedin stator cascade, aerodynamic performance of the highly-loaded compressor hasbeen significantly improved. In this paper, based on two kinds of design concept oflow-reaction compressor, a three-stage highly-loaded low-reaction boundary layersuction compressor is made out. Under the condition of the efficiency is beyond86%, a total pressure ratio of6is achieved.First of all, Rotor37and Stage35are selected to be the simulated subject toverify the precision of the numerical model. On premise of y+meeting the demandof turbulence model, by comparing with the experimental results, the influence oftotal number of grid on the simulated results is investigated. It can be found that,simulated results are almost unchanged when quantity of grid outnumbers a certainvalue. The numerical model built in this paper occupies much higher credibility.By compiling the procedure of1D and S2, preliminary design of the three-stagehighly-loaded low-reaction boundary layer suction compressor is designed, andfeasibility is validated using the numerical model. The simulated results show that,the designed compressor satisfies the preliminary requirement, however, secondar yflow in the last stage stator is much more complex, and flow at this point could notbe effectively organized even a higher suction flow rate is applied.On the basis of preliminary design, the redesign is achieved. By exchangingwith advanced blade profile, adjusting the distribution of the work and pre-whirlangle of the rotor, the aerodynamic performance of the three-stage highly-loadedcompressor gets further enhanced. On the basis of reduction in the total suctionflow rate and simplification in suction structure the final design of the three-stagehighly-loaded compressor is accomplished.In the end, the influence of meridian lines on the aerodynamic performance offirst-stage rotor and flow characteristics in compressor under different rotationspeed are investigated. As a result, for the rotor in the first stage of the low-reactioncompressor, the construction of meridian lines is a compromised procedure; underdifferent rotation speed, the suction structure could also adapt the designrequirement. The working range can get further broadened by adding an additionalsuction slot (or a certain number of suction holes).