Advanced Materials Research Vols. 622-623

Abstract: A parametric study is developed to investigate the effect of geometry, material stiffness and the rotational motion on the coupled flapwise bending and torsional vibration modes of a wind turbine blade. The assumed modes method is used to discretize the derived kinetic and potential energy terms. Lagrange’s equations are used to derive the modal equations from the discretized terms, which are solved for the vibration frequencies. The parametric study utilizes dimensional analysis techniques to study the collective influence of the investigated parameters by combining them into few non-dimensional parameters, thus providing deeper insight to the physics of the dynamic response. Results would be useful in providing rules and guidelines to be used in blade design.

Abstract: This research deals with analysis the fatique and the failure of piston engine using FEA.The objective of this research is to develop the geometry of piston engine using solidwork software and to investigate the maximum stress using stress analysis techniques to predict the failure of piston and connecting rod and identify the critical locations of the components of EF7 engine with supercharger and without supercharger. The finite element model of the components was analyzed the static stress with linear material model . first we discuss the amount of increased pressure in cylinder by supercharger and turbocharger then the influence of the inlet air pressure on the naturall aspirated engine which the main parts of its engine are not reinforced is taken account,then the result is showed the stress is increased by quantity of 273 MPA on piston and connecting rod which make the increase of fatigue on pistons and connecting rod and decrease in its period of working.The results can also significantly reduce the cost to produce the piston,and improve product reliability and improve the fatique strength and durability.

Abstract: The feeling of the brake pedal is one of the most important factors for the driver confidence during brake. Vacuum booster plays a significant role on the brake pedal feeling analysis. The traditional characteristic model cannot satisfy our objective, so a model based on the structure is needed. This paper presents a model based on the structure defined as 3 springs, 2 valves, 1 reaction washer and dynamic air flows, gives out the detailed condition to judge for the states of vacuum booster which can give more details to the brake pedal feeling. After simulation, the conclusion that the model is proper for pedal feeling can be drawn.

Abstract: The wheel loader in the muddy, slippery, ice and snow, soft ground condition working that has slippage, subsidence, instability phenomenon, at the same time efficiency and loss of work capacity. Through to the loader track wheel climbing power, obstacle negotiation ability, changes ability the simulation analysis, has carried on the confirmation to the design proposal.The simulation result indicated that the loader track wheel road surface compatible, the climbing and obstacle crossing ability are good, change nimbly.The track wheel loader longitudinal running stability, ramp driving horizontal stability theoretical analysis, obtains the loader in slope driving max gliding angle relate the friction coefficient between the tire or track and the ground. The max tilting angle related to the loader barycenter closely. Because loader track wheel is used in rubber track, and the coefficient of friction between the tire and the ground is basically the same, so replacing track wheel loader max transverse glide angle and longitudinal glide angle essentially unchanged. Combined with the SolidWorks the conversion track wheel loader barycenter analysis position results, the conversion track wheel loader barycenter and the wheel loader compared under various working conditions are reduced, so the the conversion track wheel loader stability has improved.

Abstract: 122mW green emission at 532.3nm with a conversion efficiency of 1.2% was measured by single-pass second-harmonic generation in a 10mm long periodically poled MgO:LiNbO3 (MgO:PPLN) crystal is reported. A continuous-wave Yb-doped fiber laser operating at 1064.6nm with narrow bandwidth of 0.1nm is used as pumping source. The experimental temperature acceptance bandwidth ΔT=4.6°C is a little higher than the simulation data of 4°C. Output power instabilities or variations of the green beam pattern were not observed during experiments. In this work, the optimized efficiency was achieved when the waist located at the center of MgO:PPLN and Rayleigh length equal to its length, and the lens’ location in the system was calculated.

Abstract: With the features of good electrical conductivity, and insolubilization in the electrolytic solution, Poly-Peri-Naphthalene (PPN) can be regarded as the cathode material, and there is a certain necessity to study the electrochemical properties of PPN. PPN can be synthesized easily by 3, 4, 9, 10-perylenetetracarboxylic dianhydride (PTCDA), and the related characterizations regarding to PPN is described in this paper. Meanwhile, research on the electrochemical properties of the synthesized PPN under several different temperatures has been carried out, and some basic laws have been found as follows: 1) Under the condition of 600°C≦T≦1100°Csynthesis temperature, the electrical conductivity of PPN is strengthrened with the increased temperature; 2) The discharge capacity of PPN is also increased with the increased synthesis temperature. 3) As a kind of battery cathode active material, the cyclical stability of PPN is excellent. But the capacity is small, aiming at the deficiency, nitrification treatment on the PPN has been carried out, thus the high-capacity PPN is obtained, the first discharge capacity is 342mAhg-1. Therefore, we can safely predict that the future of PPN as a lithium battery cathode material is promising.

Abstract: Glass fiber reinforced thermo plastic composite materials are finding increased applications in many areas due to their important applications. Drilling is an important operation in the final assembly of the structural frames. The life of the joining can be critically affected by the quality of the drilled holes. The delamination, fiber peel out, pull in, are important concern in drilling. The analysis of delamination in drilling and the influence of cutting parameters on thermoplastic composite materials is presented in detail.

Abstract: The combined use of ultrasonic cavitation and mechanical stirring to disperse the silicon carbide particles (SiCp) in molten aluminum alloys has been studied. Composite materials with various weight percentage of Al 6061 alloy (matrix) and SiCp (reinforcement, average particle size 10 micrometers) were fabricated. The microstructure of the composites was investigated by optical microscopy (OM) and scanning electron microscopy (SEM). The micro structural analysis validates the good dispersion of SiCp in the metal matrix. The tension test results reveal that the tensile strength of the as-cast metal matrix composites (MMCs) have been improved significantly for the 5 and 10 weight percentage of SiCp and then decreases. The hardness of MMCs increases and the ductility decreases as the particle percentage increases. The ultrasonic cavitation based fabrication is a novel route for producing wide range of MMCs.

Abstract: Wire electric discharge machining (WEDM) is one of the most popular non-conventional machining processes for machining metal matrix composites (MMCs). The present research work deals the parametric optimization of the input process parameters for response parameter during WEDM of SiC_p/6061 Al metal matrix composite (MMC). Response surface methodology (RSM) and genetic algorithm (GA) integrated with each other to optimize the process parameters. RSM has been used to plan and analyze the experiments. Four WEDM parameters namely servo voltage, pulse-on time, pulse-off time and wire feed rate were varied to study their effect on the quality of cut in SiC_p/6061 Al MMC using cutting width (kerf) as response parameter. The relationship between kerf and machining parameters has been developed by using RSM. The mathematical model thus than developed was then employed on GA to optimized the process parameters.

Abstract: Medium density fiberboard (MDF) is an engineered wood generally used in wooden industries. Drilling is the most frequently used machining operation in the assembly of furniture working. During drilling cutting forces are developed. These cutting forces are affecting the surface qualities and also causes delamination damage. The cutting conditions and the process parameters play an important role in controlling the cutting forces. The objective of this work is to study the influence of cutting parameters such as spindle speed, feed rate and point angle to reduce the cutting forces developed during drilling. Drilling tests are conducted using Taguchi design of experiments. The mathematical model is developed using response surface methodology (RSM) to evaluate the influence of spindle speed, feed rate and point angle on thrust force. It is seen that high spindle speed with low feed rate combination gives better results in drilling of MDF panels.