柴油机船舶推进装置的建模和实时仿真

本文根据准稳态的概念建立了适用于实时仿真的二冲程柴油机船舶推进装置的多阶一性模型。在充分多的试验数据的基础上，结合工作原理建立了各子系统及整个装置的动态模型，这种模型既能反映柴油机内部各参数，精度较高，计算工作量也比较适中。文中提出了一些经验公式，使模拟得以有效地简化。最后，作为实例给出了３５０００吨油船推进装置的实时仿直     

燃气轮机监测系统的建模与实现

以从法国引进的ＭＳ６００１燃气轮机发电机组为研究对象,针对它开发了一套以燃气轮机循环计算、压气机和涡轮特性计算及燃气轮机变工况计算为基础的工况监测显示系统软件。该软件的开发有利于提高燃气轮机系统运行的管理水平,为全面实现燃气轮机机组的智能监测和诊断打下坚实的基础。     

Development of Thermal Process and Numerical Modeling

IntroductionWithinrecentdecade,thenumericaIsimulationhasbeenrapidlyachievedandhasaPpliedtothermalmanufacturingprocess.ThephasetransformationiscomplicatedbythefactthatthereareseveralmicrostructuralscaIestoconsideHl1-I4].InordertorevealtheruIeofcomplexphasetransformation,itisnecessarytousethetoolofnumericalsimulationtomodelandcontroltheoverallprocessofphasetransformation.NowthecomputersimulationcangetsomereasonabIeresultSinmanyaspectsofthermalmanufacturingprocess:e.g.,thesimulationoftemperat…     

纯电动汽车前悬架设计与仿真分析

为缩短纯电动车前悬架设计的开发时间与减少开发成本,文章利用汽车设计理论对前悬架系统中悬架主要总成件进行设计,利用Adams软件对已设计的前悬架系统进行建模和动力学仿真,分析悬架性能是否符合要求。设计出悬架系统并装车试验,性能良好。,该方法可以减少样品试制的时间与成本。     

Carpooling and carpool clubs: Clarifying concepts and assessing value enhancement possibilities through a Stated Preference web survey in Lisbon, Portugal

The increase of urban traffic congestion calls for studying alternative measures for mobility management, and one of these measures is carpooling. In theory, these systems could lead to great reductions in the use of private vehicles; however, in practice they have obtained limited success for two main reasons: the psychological barriers associated with riding with strangers and poor schedule flexibility. To overcome some of the limitations of the traditional schemes, we proposed studying a carpooling club model with two main new features: establishing a base trust level for carpoolers to find compatible matches for traditional groups and at the same time allowing to search for a ride in an alternative group when the pool member has a trip schedule different from the usual one. A web-based survey was developed for the Lisbon Metropolitan Region (Portugal), including a Stated Preference experiment, to test the concept and confirm previous knowledge on these systems’ determinants. It was found through a binary logit Discrete Choice Model calibration that carpooling is still attached with lower income strata and that saving money is still an important reason for participating in it. The club itself does not show promise introducing more flexibility in these systems; however, it should provide a way for persons to interact and trust each other at least to the level of working colleagues.     

Simulation of city bus performance based on actual urban driving cycle in China

This paper establishes the simulation model of a city bus on the basis of the EQ6110 bus prototype and its experimental data. According to the actual urban driving cycle, the fuel economy and the traction performance of the EQ6110 city bus have been simulated, and factors such as the driving cycle, the loss of power to engine accessories, the gear-shifting strategy, the fuel shut-off strategy of the engine, etc., which influence on the bus’s fuel economy, are also quantitatively analyzed. Some conclusions are drawn as follows: (1) driving cycles have a great influence on the fuel economy of a city bus; (2) under the typical urban driving cycle of the public bus in China, the engine fuel shut-off strategy can save about 1 to 1.5 percent of the fuel consumption; and (3) the optimized gear-shifting rules can save 6.7 percent of the fuel consumption. Experimental results verify that the fuel economy for the EQ6110 public bus is improved by 7.2 pecent over the actual Wuhan urban driving cycle of the current public bus in China.     

基于车辆平顺性分析的橡胶衬套动态特性建模

橡胶衬套的动态特性与载荷的激振频率、幅值等因素相关,其模型的准确性影响车辆平顺性的仿真精度。建立了包含材料弹性、粘弹性与弹塑性的橡胶衬套动态模型,分别采用多项式、分数导数与Bouc-wen模型描述橡胶衬套的弹性、频率相关性及振幅相关性。通过参数辨识确定衬套模型参数并进行仿真,验证了所建模型的准确性。     

The importance of estuarine gravitational circulation in the early life of the Bohai Penaeid Prawn

Estuaries along the southern shore of the Bohai Sea are the major habitat of the Bohai Penaeid Prawn (Penaeus chinensis). Since the 80's, however, many of the rivers have been dammed. Field observations, as well as laterally integrated 2-D numerical experiments, were conducted to understand both the role of estuarine gravitational circulation and the impact of the damming of the rivers on the early life of the Bohai Penaeid Prawn.For a river with runoff, especially for small discharge, the gravitational circulation tends to transport the planktonic larvae in their metamorphosis phase near the river mouth where condition is favorable for survival. The gravitational circulation inside the estuary tends to transport the mysis phase larvae towards the upstream end of the estuary when the most part of the larvae suspended in the bottom layer, and it transports the post larvae to the low salinity near upstream side of the estuary when the larvae become benthic, if the larvae enter the estuary.Damming causes long periods of zero runoff in the river, resulting in the alteration of the estuarine circulation and in the change of the estuarine environment. In addition, excess evaporation may prematurely transport the planktonic larvae into the estuary. On the other hand, sudden release of a large volume of freshwater from behind the dam may exert undesirable stress on the larvae.     

选择性输出双离合自动变速器换挡仿真

为提高我国车企的竞争优势,文章介绍一种具有自主发明专利技术的双离合自动变速器(DCT)的结构及工作原理。并利用Matlab/Simulink仿真软件,建立了整车系统动力学模型,包括发动机、双离合自动变速器、车体及其他负载。在此基础上进行DCT的换挡过程仿真分析,研究其控制策略。仿真实验结果验证了所建立数学模型的合理性和可行性,提高了DCT动力系统设计的效率。仿真结果表明该方法正确可行。     

一种CATIA建模方法

随我国汽车开发技术的发展和汽车市场的竞争日趋激烈,整车开发周期就尤其重要,但车身开发周期直接影响整车的开发周期,CATIA建模结果又是影响车身开发工作效率和降低车身开发周期的重要因素之一。