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In the calculation of the reliability of hydraulic, due to extensive uncertainties, there are lots of errors in probabilistic reliability analysis. In this paper, by comparing the non-probabilistic reliability index of different function, we get the advantages and disadvantages of one-dimensional optimization algorithm and method of Monte Carlo, and compare the functions of each variable of main beam to obtain the influence of the precision of the variables.

An accurate three-dimensional flow passage model of the compressor has been created; the stress distribution of the main flow channel has been obtained. The aerodynamic force was applied to the impeller blades. Three kinds of loads were applied to the main blades and splitter blades. Modal characteristics of the compressor blades have been intensively studied.

To facilitate the independent learning and safety experiments, the network virtual laboratory is one of the hot spots of the current research. After analyzing advantages and disadvantages of the current virtual laboratory, this paper introduces the web-based and self-adaptive virtual laboratory platform, with a three-tier structure of the B/S mode. And the platform has two groups of users: teachers and students. Teachers can customize experiments which can be performed by students in the platform. The formation of the experiment consists of two parts: the equipment based on object-oriented ideas and used geometric modeling technology, which has more realistic effect, and achieves real-time rendering; And environmental background using cylindrical panoramic technology, which has photo effects, and loading faster. These two parts is combined through photography geometric principles. The experiment proved that in this virtual laboratory platform, the experiment is loading fast, have stronger sense of immersion and effectively improve the students' network learning efficiency.

A quantitative method for evaluating the casting complexity has been elaborated in the present paper. It was consisted of two aspects, one is the casting geometry structure complexity, and the other one is the casting shape-forming complexity. The casting geometry structure complex degree can be described in a quantitative form based on the basic tissues that compose the casting, the geometry structure complexity is C=-[n1log(n1/N)+n2log(n2)/N+...+nklog(nk/N)] . And the casting shape-forming complex degree can be estimated by the surface modulus and its distribution characteristics at x, y, z coordinates. When the casting geometry structure is complex and the shape-forming is complex, the casting can be defined as “complicated casting”.

Microporosity in both HIPped and non-HIPped unmodified aluminum cast alloy A356-T6 was quantified metallographically in terms of its area, area percentage, length, sphericity and perimeter. In the studied materials, the secondary dendrite arm spacing (SDAS) values vary from 82μm to 96μm for both the HIPped and the non-HIPped castings. HIPping process significantly reduces porosity area fraction and pore sizes. The maximum area fraction of porosity and maximum pore area of the non-HIPped specimens are increased with increasing SDAS.