Abstract: Due to the difficulty in large gear modification, a method that modifying gear tooth in the processing through correcting gear cutter was proposed. In this paper, modification theory of large gear and design method of gear cutter were introduced in detail. Based on gear meshing theory, the tooth equation of large gear was deduced from the equation of correcting cutter. The processing was simulated by using Matlab software, and it verified the validity of theoretical analysis.
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. Developed a kind of the conversion track wheel,It can replace the tire. Study on the conversion track wheel loader stability performance.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: The dynamic model of a class of the system coupled with main rigid body, elastomer and tip rigid body is established. The control law of the system is given, and the attitude stability of the complex controlled system is studied in infinite dimensional functional spaces by means of the modern mathematics and large scale system analysis.
Abstract: This paper proposes particle swarm optimization (PSO) for identification of the Proton Exchange Membrane Fuel Cells (PEMFC) generation systems fuzzy model. The PEM fuel cell generation system efficiency decreases as its output power increases. Thus, an optimum efficiency should exist and should result in a cost-effective PEM fuel cell generation system. The PEMFC generation system cost and efficiency fuzzy model were build, we use the PSO as an optimization engine to indentify the fuzzy model. The simulation results were presented and the results show that we may minimize the total cost of the generation system by using the PSO.
Abstract: A special hand-grate boiler burning biomass of straw and brushwood with natural ventilation is introduced. The tested thermal efficiency of the boiler is higher than 61% and has good potential of energy saving and environmental protection, thus meets the need of heat supply under operation condition. A wide market of the boiler in remote regions is expected.
Abstract: In order to study the electrical ignition method of liquid propellant spray, two experimental devices of liquid propellant spray and alternating current (AC) pulse discharge were designed. By using of high speed digital camera system, the test on electrical ignition of HAN-based liquid propellant LP1846 spray were carried out under different injection pressures. The results show that under 50W AC pulse discharge conditions, LP1846 droplet cluster, with the mean diameter in the range of 20~40μm, can be ignited reliably. Based on above experiments, a simplified model of ignition delay time of LP1846 single droplet was set up, the calculation value is well matched with the experimental data.
Abstract: The analysis on the characteristics of each period in the starting process for common rail diesel engine was carried out. Rail pressure simulation model in the starting process was set by Matlab/Simulink. And rail pressure was tested in 4JB1 high pressure common rail diesel engine. The experimental results showed that idle rail pressure and engine speed fluctuated severely. Solution to correction of duty of metering unit(MeUn) at initial period was proposed, and effect of dragged laps on duty of MeUn was added in control strategy. The improved experimental results showed that amplitude of rail pressure fluctuation was very small and idle speed was no longer overshoot. The performance of diesel engine in the starting process has been greatly improved.
Abstract: By doing modal analysis of the whole wind turbine system, we can get the first twenty orders natural frequencies and corresponding mode shapes, By analyzing the dynamic characteristics of the blade, the weakness points of blade were fund. Under rotor rotating excitation in the normal state, mass eccentricity states and stiffness damage states of blade, the strain energy change rates (SECR) of nacelle are obtained. While based on the SECR of nacelle, the methods of strain energy change rate and support vector machine are introduced to indentify locate the mass eccentricity and stiffness damages of blade. The research show that mass eccentricity and stiffness damages at different location and in different degree can be efficiency identified and forecasted by means of support vector machine classification method.
Abstract: Butanol has been considered an attractive alternative fuel for automotive engine. In the present study, a numerical study is conducted in a spark-ignition engine fuelled with blends of gasoline and 1-butanol at different fuel/air equivalence ratios. The effect of fuel/air equivalence ratio on engine performance is analyzed. The results show that the peak pressure and peak temperature increases with the increasing of fuel/air equivalence ratio. With increased 1-butanol proportion, the incylinder pressure and incylinder temperature gradually decreases. In addition, effect of fuel/air equivalence ratio on nitrogen monoxide emission is depended on the proportion of 1-butanol in blended fuels.
Abstract: The potential of controlling premixed compression ignition (PCI) combustion by two fuels with different ignitability and volatility was studied numerically by a three-dimensional computational fluid dynamics (CFD) model. The results indicate that the addition of gasoline to diesel fueled PCI engine can retard the ignition timing, lower the in-cylinder temperature, and reduce the exhaust emissions.