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An integrated analytical method based on multidisciplinary optimization software Isight and general finite element software ANSYS was proposed in this paper. Firstly, a two-disk rotor system was established and the mode, humorous response and transient response at acceleration condition were analyzed with ANSYS. The dynamic characteristics of the two-disk rotor system were achieved. On this basis, the two-disk rotor model was integrated to the multidisciplinary design optimization software Isight. According to the design of experiment (DOE) and the dynamic characteristics, the optimization variables, optimization objectives and constraints were confirmed. After that, the multi-objective design optimization of the transient process was carried out with three different global optimization algorithms including Evolutionary Optimization Algorithm, MultiIsland Genetic Algorithm and Pointer Automatic Optimizer. The optimum position of the two-disk rotor system was obtained at the specified constraints. Meanwhile, the accuracy and calculation numbers of different optimization algorithms were compared. The optimization results indicated that the rotor vibration reached the minimum value and the design efficiency and quality were improved by the multidisciplinary design optimization in the case of meeting the design requirements, which provided the reference to improve the design efficiency and reliability of the aero-engine rotor.

In this work, spodumene/mullite ceramics with low thermal expansion were successfully prepared from spodumene, quartz, talc, and clay. The effects of spodumene content and sintering temperature on the mechanical properties of spodumene/mullite ceramics were investigated. The formed phases were then detected by X‐ray diffraction analysis and the microstructures of the sintered bodies were determined by scanning electron microscopy. The interaction effects of the spodumene content and sintering temperature on the apparent porosity and bulk density were studied by response surface methodology. The results demonstrate that an appropriate sintering temperature and spodumene content can promote densification, improve the mechanical properties, and reduce the coefficient of thermal expansion (CTE) of spodumene/mullite ceramics. At the spodumene content of 40 wt.%, the sintering temperature of 1270°C, and the holding time of 90 min, the bending strength was 60.45 MPa, the CTE was 1.73 × 10–6/°C (α[25–650°C] < 2 × 10–6/°C), the bulk density was 2.28 g cm‐3, and the apparent porosity was 0.43%. Therefore, this study was of guiding significance for reducing the production cost of spodumene low thermal expansion ceramics and improving product quality.

The vibration optimum design for a simulated power turbine rotor without blades on the disk by using an optimization method based on the finite element method is described in this paper. The installation position of the two-stage turbine disks is chosen as design variables under the constraints of feasible regions for the critical speeds of the rotor. The objective functions are to minimize the transient response of the acceleration at the bearings and the amplitude of the disks. Predictions of the dynamic characteristics of the rotor are obtained by using ANSYS code. The optimization problem is solved by using commercial optimization code ISIGHT. The optimum installation position of the two-stage turbine disks is determined after optimization design. Experimental tests under the optimized structure show that the amplitude of the two-stage turbine disks which are recognized as the most concerned optimization objectives are reduced by 59 % and 56 % respectively in comparison with the comparative structure. The encouraging results demonstrate the potential of the presented method as an engineering design tool and also lay a foundation for the design of the real power turbine rotor used in turbo-shaft engine.