Analysis of the Wheel Loader Hydraulic Hybrid System Based on Braking Energy Recovery

The wheel loader will release a lot of energy in the process of reducing the speed and braking. In the paper it introduced the types and features of the loader hydraulic hybrid system, analyzed configuration, energy saving scheme and working state of the loader parallel hydraulic hybrid system. The results show that the parallel hydraulic hybrid system is applied to the loader, not only it can efficiently recovery braking energy, but also it can improve the dynamic performance of the loader, so the engine can work in the optimal fuel economy area, improve fuel economy.

Study on Impact Collapse Characteristics of CFRP Double-Hat Members According to Stacking Angle

There has been greater demand on fuel mileage improvement and reduced CO2 emission in automobile without sacrificing safety. To meet these requirements, light weight car body is widely adopted. In addition, advanced country already started the strict regulation on fuel mileage and exhaust gas emission because of energy depletion by automobile and severe environmental contamination. Especially, during the initial stage of car design, side member of front side that absorbs significant amount of energy should be precisely evaluated for collapsing and energy absorption prior to estimate safety performance on frontal collision of car. Therefore, CFRP double hat and hat-shaped member were prepared to supplement the issues of splitting between “ᄃ” shaped member and planar one. According to stacking configuration, energy absorption characteristics via impact collapsing experiment were evaluated to acquire CFRP double-hat shaped member.

Studies of Trans- and Cis-Xylomollin Molecular Structures Using Molecular Dynamics Simulations

The present work describes the comparative study of the trans- and the cis-xylomollin structures. We have determined the two bridgehead H5 and H9 configurations using simulation calculations for both trans- and cis- distereoisomers. Molecular Dynamic (MD) simulations of the trans- and cis- xylomollin were performed with an efficient program. The geometries, interaction energies, bonds, angles, and the Van der Waals (VDW) interactions were carried out in solution and gas phases. This comparative study shows that the trans-xylomollin acquires the high configuration energy under the AMBER field using MD method. This molecule reaches its high stable configuration state in solution environment. Our MD simulation results are goods and in agreement with those of literature.

THE OPTIMAL CONFIGURATION OF GEL SHEET GOVERNED BY ITS CONCENTRATION

We investigate the configuration of gel sheets with centrosymmetric distribution of monomer concentration in this paper. The configuration energy of these gel sheets consists of the in-plane stretching energy and bending energy. The equilibrium shape equations are derived by variation principle. This provides a way to control the shape of gel sheets by the initial concentration and thickness. From the equilibrium shape equations, we know that the Gaussian curvature on boundary (K|C) of equilibrium shape is determined by the Poisson ratio [Formula: see text]. K|C is negative when [Formula: see text] but positive when [Formula: see text]. Specially, we derive two dome-like solutions from the equilibrium shape equations to compare with the experimental data. In these dome-like sheets, on the boundary part the Gaussian curvature is K < 0, which is different from the center part (K > 0). Furthermore, we deduce that the initial gel distribution of cylinder sheets is proportional to 1/r and find that N-isopropylacrylamide cylinder sheets cannot be formed without additional edges. Our theoretical results agree well with the experimental data [Klein et al., Science315, 1116 (2007)]. On the other hand, we predict a special type of gel sheets as minimal surface. Their residual stresses are constant and same along radial and circumference directions. For axisymmetric sheets, we give a criterion about the sign of Gaussian curvature K when thickness h is infinite small.