Applied Mechanics and Materials Vols. 117-119

Abstract: Abstract: A model of leaf spring composed with ten spring laminations is established by the language of APDL. The model is loaded with pre-stress, static stress and Grade B Road stress, then the results is calculated. Finally, applying the PDS unit of ANSYS, the reliability of leaf spring is worked out. As an important hanging form in the vehicle, the leaf spring is widely used in auto, besides the reliability of a car mostly depends on it. So, it is necessary to deeply study its designing method and reliability^[1,2].

Abstract: Soy protein isolate(SPI) based edible film as matrix materials have been prepared using the casting techniques. Ultrasound treatment (UT) could represent an interesting strategy for improving Soy protein film appearance. Different UT exposure times were applied to film-forming dispersion. The aim of this work was to investigate the effect of ultrasound treatment on Soy protein films at molecular structure and mechanical properties. The results showed that the structure of SPI film became more homogeneous and the properties has been improved largely after treated by ultrasonic, with the output power 1000 w for 16 s the tensile strength was the best; for 12 s, elongation reach the peak.

Abstract: Wear debris in hydraulic oil causes most of the faults of hydraulic system and is also an important information carrier, so it is essential to check the condition of wear debris in hydraulic oil. On the basis of inductive principle and microfluidic chip technology, the design of a microfluidic chip of oil detection is presented in this paper. the relation between coil geometry parameters and inductive change of planar inductor are analyzed through the related experimental statistics, the result being that when the ferrous metallic particle flows through planar inductor, the measured inductance variation increases with the number of turns and decreases with the coil line width.

Abstract: With the fast development of the natural gas industry, volcanic gas reservoirs have been paid an increasing attention. Many deep gas wells in volcanic reservoirs have special characteristics, such as high temperature, high pressure and high level of CO₂ with strong corrosion effect, which brings great challenge to the safety of the tubing. Therefore, the mechanical analysis of tubing in deep gas wells in volcanic reservoirs is helpful to design the strings, optimize operation parameters and predict service life. In this paper, based on the buckling analysis, a mechanical model of tubing is established and solved by stepwise iterative algorithm. Physical properties of tubular strings and fluid are taken into consideration in new model, as well as the pitting corrosion of CO₂. A program also developed for practical purposes. The results can be applied for the safety assessment and life prediction of the tubing in deep gas wells in volcanic reservoirs.

Abstract: After the research of detailed geological exploration report, as well as the selection and optimization of foundation processing programs, dynamic compaction method with reinforced plastic drainage board is chosen to achieve good results, shorten the duration and reduce the cost.

Abstract: In this paper, the crushing behavior of stepped circular tubes under oblique compression is studied by finite element method (FEM) analysis. It is found that the stepped circular tubes exhibit good response to oblique load. The deformation of the tubes can be classified into stable and unstable modes depending on whether break point is observed in the compressive load curve. In the stable mode, the tube stays erect and absorbs compressive energy to the same extent as it absorbs axial load. However, in the unstable mode, the tube does not stay erect and can bear only much lower compressive load than that of axial crushing. The two deformation modes can be controlled by the geometry of the tube. The compressive load of the stepped tube under oblique crushing increases as the difference between the radius of the large tube and small tube decreases and as the total length of the tube increases. For geometries that take values near the boundary between the stable and unstable modes in the mode map, the stepped tubes exhibit maximum absorption efficiency. Moreover, the absorption efficiency of stepped tubes is proportional to thickness to about the 1.8 power.

Abstract: Because of the variety of processing methods, broad range and uncertainty of processing parameters when machining aeroengine structure parts, the method of fuzzy orthogonal optimization was used to optimize milling parameters in the light of machining efficiency in machining plane characteristics of aeroengine structure parts. According to analyzing the effects of milling parameters on processing efficiency, the optimized parameters were obtained. The results showed that the established fuzzy orthogonal optimization model can take full account of the uncertainty in the process of cutting parameters optimization. Excellent experimental agreement was achieved in cutting parameters calculated by the established model. The established model has good practicality and high precision. It is easy to understand and can be used to guide the actual production.

Abstract: When the aircraft skin is in the process of trimming and on the flexible vacuum cup fixture, by analyzing the stress to the aircraft skin and studying the relationship between vacuum pressure and deformation of aircraft skin, vacuum pressure, vacuum force and cutting parameters, the relationship which between vacuum pressure of flexible fixture and cutting parameters, clamping points of flexible fixture, friction coefficient of cup and aircraft skin, the maximum deformation allowed on aircraft skin is obtained. It provides a methodology to improve the precision of trimming of aircraft skin components.

Abstract: Based on Kelvin model, the large deformations of elastomeric foams were simulated by finite element method (FEM). Numerical results indicated that edge bending, edge stretching and edge torsion were important deformation mechanisms of low density open-cell Kelvin foam. The hyperelasticity of the cell material had little effect on the macro-mechanical properties of the foam at low strain in [111] direction and finite compressive strain in [100] direction when edge bending was the main deformation mechanism of the foams. With the increase of the uniaxial tensile strain, edge stretching played notable roles, which resulted in that the hyperelasticity of the solid had significantly influence on the deformation of the foam at large uniaxial tensile strain. And the high strain compressive stress-strain curves in the [111] direction based on the hyperelastic relation differed from the linear elastic results remarkably as edge torsion was an important deformation mechanism of the foam.

Abstract: The character of lines and high-speed performance of trimaran planing hull is briefly introduced. By use of model experiments the law of longitudinal motion stability of the trimaran planing hull is studied. According to the combination of upper and lower speed limits at which the dolphin motion takes place at different displacements and the positions of gravity, these critical points from the experiments are linearly fitted by using MATLAB in order to obtain the limit curve. The veracity of the limit curve to evaluate the longitudinal stability is proved.