Experimental investigations have been carried out on the flow characteristics of the last stage long blades operating under off-design conditions. A model turbine test rig similar to a small power station was applied. The last stage blades with a scaling factor of 1 : 4.8 was used for pneumatic experiments. The rotor blade height was 375 mm, and the rotation speed was set to 7200 rpm. Five volumetric flow coefficients were utilized, corresponding to φ =0.61, 0.77, 0.92, 1.02, and 1.15. Pneumatic probes were used to focus on measuring pressures and swirl angles. The variation of different pneumatic parameters along the span and circumferential direction was investigated. The change patterns of the three-dimensional aerodynamic characteristics of the last stage blades during the off-design conditions were revealed. Results indicated that there was a high correlation between the variation of pneumatic parameters and different off-design conditions. In particular, the large meridional expansion angle at the tip led to abrupt changes in the inlet parameters, and the overlap even occupied by 17% blade height. Due to the influence of the exhaust hood, the circumferential static pressure-unevenness was up to 77.8% at the last stage outlet.

A numerical method was used to investigate the reaction degree effects on the aerodynamic performance and flow structure of the single-stage transonic turbine. The SST-γ-θ turbulence model was employed to predict a transition for the boundary layer near the blade surface. This work utilized a public PW-E3 blade profile from NASA. Five different reaction degrees were adopted, corresponding to Ω = 0.15, 0.27, 0.33, 0.44 and 0.59. In addition, different off-design conditions were considered with three reaction degrees. The efficiency, blade surface pressure and high Mach number distributions were significantly associated with the reaction degrees. Results indicated that the highest efficiency point was observed at Ω = 0.33. The trailing edge shocks and the reflected waves were visible in the cascade channels. The Shock wave was easily detected in the stator channel at lower reaction degrees while it was displayed in a rotor with a higher reaction degree. When the reaction degree was increased, the high Mach number region was expanded in the rotor channels while it was reduced in stators. Besides, the highest efficiency points were also observed around π = 1.5 for all operating conditions. Furthermore, the critical pressure ratio was discovered and the maximum mass flow rate gradually decreases as the reaction degree increases.

The research on competitive priorities has been focused on the field of manufacturing strategy in the last 20 years. Based on the literature of manufacturing strategy competitive priorities Ämanufacturing competenceÅ, we develop a relationship model consists of time, cost, quality and innovation, and depict how these four dimensions of competitive priorities in combination affect the manufacturing performance. Moreover, we propose the hypothesis: in the good innovation environment, the four factors of TCQ&I model in the enterprise have the following relations: Quality seems more important than innovation, innovation seems more important than cost, cost seems more important than time. This paper regards the developed country as good innovation environment, namely the quality and innovation factors are to be essential to the entire manufacturing system in the developed countries. The innovation factor in developing countries has a lower position than in the developed country. This paper uses the data from the database of the International Manufacturing Strategy Survey (IMSS). The factor analysis, model fitting analysis and multiple regression analysis research methods are used. We also use the cluster analysis method to contrast the developing country with the developed country. The statistical analysis tool applied is the LISREL software. The results prove the validity of the hypothesis.This study concludes that the TCQ&I model, which includes innovation, is reasonable. The manufacturing in developed countries such as china must highlight the importance of the innovation. They should strengthen the self-innovation capacity and fulfill the quality management to construct the effective manufacturing competitive priority system in the enterprise. Meanwhile, they should also attach importance to the cooperation between developing countries.

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