Advanced Materials Research Vols. 960-961

Abstract: we studied the spray characteristics of n-butanol/diesel fuel blends using a high-speed camera and schlieren system, and analyzed the effect of different fuels, ambient pressure and injection pressure conditions on the spray penetration, spray cone angle, spray area, et al. The results showed that, at the same injection pressure, as the increase of ambient pressure, the spray cone angle of the same volume of fuel increases gradually, the spray penetration and the spray area decreases; under the same ambient pressure, the spray penetration, spray cone angle and spray area increase gradually with the increasing injection pressure, but when the injection pressure increases enough, the parameters are roughly the same; and the parameters basically all increase with the adding of n-butanol.

Abstract: The authors present extreme learning machine (ELM) as a novel mechanism for diagnosing the faults of rotating machinery, which is reflected from the power spectrum of the vibration signals. Extreme learning machine was originally developed for the single-hidden layer feedforward neural network (SLFN) and then extended to the generalized SLFN. We obtained the fault feature table of rotating machinery by wavelet packet analysis of the power spectrum, then trained and diagnosed the fault feature table with extreme learning machine. Diagnostic results show that the extreme learning machine method achieves higher diagnostic accuracy than the probabilistic neural network (PNN) method, exhibiting superior diagnostic performance. In addition, the diagnosis of fault feature table adding noise signal indicates the extreme learning machine method provides satisfactory generalization performance.

Abstract: The optimum inlet temperature for different engine conditions was calculated based on the same knock probability with full load by CFD Fire software, and then the effects of inlet air heated on combustion,pumping loss and emissions of gasoline engine were also studied. The results showed that the highest intake temperature at intake pressure 50kPa operation can be 368K without knock, and that for 100kPa condition was 322K. Heating inlet air can enhance combustion, and the maximum combustion pressure was increased by 26.8% and IMEP by 4% at the case of 368K/50kPa condition compared with inlet pressure of 40.5kPa and temperature of 298K condition consuming same fuel. Pumping loss can also be reduced by increasing intake temperature. However, emissions of NO_X and CO were increased because of higher intake temperature.

Abstract: On the basis of original engine, high compression ratio miller cycle can be realized, through perfecting the inlet cam profile, using higher geometry compression ratio, combining VVT control technology. The results indicate that the miller cycle achieved by VVT control technology can reduce pumping loss, and improve the effect utilization of energy. The combustion heat release rate is lower than the original engine, and combustion heat release are mainly concentrated on TDC later, lower the burning temperature. Compared with the original engine, NO_X emissions decrease significantly, but CO and HC emissions increase somewhat.

Abstract: The effect of fuel auto-ignition quality on particle size distribution and particulates morphology were investigated for the purpose of revealing the relationship between cetane number and particles emission. Experiments were conducted on common-rail direct injection engine under steady-state operating condition. Two basic diesel-like fuels were used in this study, hydrogenation diesel and straight-run diesel. The test fuels which have various cetane number were made up of these two basic ones. The results indicate that with increasing the fuel cetane number, a significant decrease of nucleation mode particles is found. For particle number size classification, the percentage of SOF has the same trend as the number of nucleation mode particles which size below 22nm and similar result is found between the percentage of dry soot and particles above 50nm.

Abstract: Based on Solidworks software, the three-dimensional model of two wheels scooter is set up. The finite element model of two wheels scooter is generated. Modal analysis of driving system and telescopic mechanism of bar on two wheels scooter is investigated. The first five orders natural frequency and major modes of driving system and telescopic mechanism of bar are clarified. The method and the result can be used as a reference of dynamic design and lay foundation for calculation and analysis of dynamic response for the two wheels scooter.

Abstract: In the present power system stability analysis, BPA model for turbine and governor is commonly used. It simplifies the actual turbine system to a large extent, therefore the model simulation results may deviate from the actual conditions. In order to improve the actual data simulation accuracy, this paper compared the real and simulation data of power, high pressure cylinder (HPC) exhaust pressure and reheat pressure. Then calibrated and optimized the established model using the data of field operation. Meanwhile, the model modified method using actual data is given and guidance of parameters tests is offered.

Abstract: This article from the market background and market current situation analysis, on the current market of forklift insufficiency and flaw analysis, found a multi-purpose vehicle is very suitable for the market current situation, so the multifunctional automatic change of engineering vehicle design. Then the main function are introduced, design, calculation, through modeling, error analysis and Solidworks analysis, design a reasonable multi-functional automatic replacement vehicle structure. finally introduced multi-function automatic change the character of engineering vehicles, introduce market prospect.

Abstract: Jam fault occurs most times in the hydraulic servo system, and is the one of the factors that mainly influences the reliability of the system. For parallel-operated turbine, the jam faults of regulating system are elusive and fatal. In order to monitor operation condition and improve the reliability of the system online, the model of jam fault had been built, the sizes of the dead zones which describe jam fault had been viewed as unmeasured parameters, which avoided the model uncertainty brought by the linearization of nonlinear system, and strong tracking filter had been used to estimate unmeasured parameter. Simulation and experimental results verified that, this technique could accurately, synchronously estimate respective degrees of jam faults of slide valve and pilot valve online whether in daily operation or moving test.

Abstract: With the rapid development of China's interconnected power grid, power system operation environment has become increasingly complex. The safety and stability of the power system requirements are also increasing. Turbine is an important basis for the analysis of power system stability. This paper studied the influence of turbine parameters related to network on the stability of the grid from the perspective of the frequency domain, and obtained the impact properties of turbine speed control system parameters related to different oscillation frequency of the power system. The conclusions are validated from time domain. So that when analyzing the stability of the power system, a more targeted turbine model according to different research purposes can be chosen because the parameters’ importance can show the necessity of the modules.