With finite difference code Flac3D, the stability of loess slope with hidden hole at different locations has been evaluated. Failure mechanism of loess slope is also studied. Under plane strain conditions, the results of numerical simulation show that the existence of hidden hole has a direct impact on the stability of the loess slope, and sometimes decreases the safety factor. The failure of hidden hole also directly affects on the overall destruction of slope. Consequently, at the stage of loess slope design, it is necessary to carefully evaluate the stability of loess slope with hidden hole. Particularly, it is important to consider the influence of stability by the position of hidden hole in loess slope.

In the paper, on the basis of three-dimensional Reynolds-averaged Navier-Stokes equations and the RNG κ-ε turbulence model, adopting Three-dimensional unstructured grid and pressure connection the implicit correction SIMPLEC algorithm, and using MRF model which is supported by Fluent, this paper carries out numerical simulation of the internal flow of the centrifugal pump in different operation points. According to the results of numerical simulation, this paper analyzes the bad flow phenomena of the centrifugal pump, and puts forward suggests about configuration perfected of the centrifugal pump. In addition, this paper is also predicted the experimental value of the centrifugal pump performance, which is corresponding well with the measured value.

Consideration of influence of the groundwater seepage and supporting measures to deep-foundation pit,the deformation characteristics of surrounding soil of the foundation pit are given. Seepage and deformation characteristics of surrounding soil are simulated to predict deformation of the deep foundation in ha er bing and stability of deep-foundation pit is analyzed base on the influence of the seepage. The analysis results are compared with observed data and it is showed that the calculated results with the model considering coupling response of permeability coefficient are closer to observed value than those results with the other model. So, the model considering fully coupling response of permeability coefficient is reliable and applicable.