Prismatic Shaft Compressor Unit System Design And Experimental Study

As basic equipment, compressor is widely used in various fields sush asautomotive and chemicals. The screw compressor widely applied in the market atpresent has disadvantages that the cost of processing the rotors is high, and the screwcompressor has low work efficiency at low speed. Prismatic shaft compressor is anew-type compressor and has the similar operating principles as the screw compressor.Compared with the screw compressor, prismatic shaft compressor with unique typelines of rotors has advantages that the cost of processing rotors is low, prismatic shaftcompressor works at low speed and has high work efficiency.In this thesis, the components of the prototype were designed. The formulas ofvolume flow, volumetric efficiency, shaft power, adiabatic efficiency and the volume oflubricating oil injected were derived. What’s more, actual shaft power and volume flowof oil were calculated. The working processes were analyzed and unit system ofprismatic shaft compressor was designed.Based on CFD simulation software Fluent, two-dimensional geometric models ofprismatic shaft compressor were built, appropriate calculating model and solvingmethod were selected, the working processes were simulated, and flow fields atdifferent moments were obtained. Different models were established to analyze theinfluence which the distance of two rotors and rotor-tip clearance had on exhaustpressure. For one model, the influence that the speed of rotor had on exhaust pressurewas analyzed. The results of simulation proved that the more distance of two rotors androtor-tip clearance, the lower exhaust pressure, and for one model, the higher speed, thehigher exhaust pressure.After the prototype was processed, installed and adjusted, the experiments ofrunning-in and unit system were conducted, and the exhaust pressures at two differentspeeds were obtained. The results of experiments indicated that prismatic shaftcompressor can obtain common exhaust pressure of0.7MPa at a low speed of2189r/min, and it demaonstrated that prismatic shaft compressor can meet the needs ofpractical engineering applications. Compared the results of adjustment and experient, itshowed that injecting oil discontinously had influence on exhaust pressure.Comparedthe results of simulation and experiment, it drew conclusions that the data of simulationand experiment were equal, and it was feasible to analyze the flow fields and predict theresults of the experiments of prismatic shaft compressor by Fluent simulation software.