Structural Seismic Input Model on the Condition of Slope Site

The viscoelastic artificial boundary model is widely used in the field of earthquake resistance analysis of water conservancy projects and nuclear power stations. However, for the analysis of soil-structure dynamic interaction on the sloping site, some problems will arise while using that method. The large size difference of side facades on the outer boundary will cause inconsistent horizontal seismic forces, which may lead to the divergent results or the drift of displacement. In this chapter, based on the basic formula of dynamic interaction and seismic input mechanism, a virtual symmetrical substructure system is built to solve those problems, which not only satisfies the consistence of the whole seismic input on the outer boundary but also simulates the seismic wave propagation. Finally, the accuracy and the stability of the new method are verified through numerical examples on the sloping site

A new Pachpatte type dynamic inequality on time scales

In this paper, using the comparison theorem, we investigate a new Pachpatte type dynamic inequality on time scales, which provides explicit bounds on unknown functions. Our result unifies and extends a continuous inequality and its corresponding discrete analogues

Experimental investigation of wall thickness and hole shape variation effects on full-coverage film cooling performance for a gas turbine vane

The effects of wall thickness and hole shape variation on a full-coverage film cooled turbine vane are investigated in a stationary and linear cascade utilizing the pressure sensitive paint technique. The varied wall thickness produces hole length-to-diameter ratio (L/D) in a range from L/D = 2 to 5, and holes tested include simple angle hole, compound angle hole, and fan-shaped hole. Five rows of holes are provided on the pressure side while three rows of holes are provided on the suction side, with six rows of cylindrical holes drilled on the leading edge to construct showerhead film cooling. The tested blowing ratios for the showerhead, pressure side, and suction side range from 0.25 to 1.5, with a density ratio of 1.5. The freestream Reynolds number is 1.35 × 105, based on the axial chord length and the inlet velocity, with a freestream turbulence intensity level of 3.5% at the cascade inlet. The results indicate that the wall thickness variation produces significant influence on the pressure side film cooling effectiveness, while only marginal effect on the showerhead and suction side film cooling. Also observed is that the fan-shaped hole generates the highest film cooling effectiveness on pressure or suction side. Also discussed is the surface curvature effect, combining with effects of wall thickness and hole shape variations, on the film cooling effectiveness in comparison to the flat-plate data