共查询到20条相似文献，搜索用时 31 毫秒
1.
借助于虚拟样机技术及其支持的UG、MSC．ADAMS以及MSC．Patran软件,建立4V-105柴油机的曲柄连杆机构的模型,通过对该机构进行动态模拟,获得了4V-105柴油机工况运行时的特性数据,为分析该型号柴油机连杆可靠性提供了有价值的依据。 相似文献
2.
针对本田CBR600发动机重心过高问题,重新设计了新的油底壳,降低了59 mm的发动机重心高度,利用ANSYS-VOF模型对两种方案进行对比分析,得出采用“菱形”挡板布置的油底壳具有更好的减晃性能。为避开发动机和地面激励,利用ANSYS-Model模块对新设计的油底壳进行了模态分析,结果表明,油底壳固有频率有效避开了激振频率。装配新设计油底壳的发动机搭载在某学院第三代赛车上,通过近千公里的测试、比赛验证了方案的可靠性。 相似文献
3.
刘成武吴平李喆施京凯吴铭 《福建工程学院学报》2021,(1):1-6
基于Hyperworks软件对某电池包精细化建模,然后进行多工况和约束模态仿真。仿真结果表明,该电池包在颠簸路面刹车和加速工况下均能满足条件,但在约束模态分析中前两阶模态较低,其中上盖板与路面激振频率接近,产生共振对电池造成破坏。运用Optistruct中的厚度优化方法对上盖进行优化,优化后再次建模仿真。优化后一阶约束模态达到28.4Hz,有效避开了来自路面的共振频率,研究结果可为电池包结构设计提供依据。 相似文献
4.
为了研究不同频率的激振力叠加作用下平板叶片的位移响应变化,在平板叶片上选取激励点和多个响应点进行相关性激励试验。试验中,首先运用设计的加法器对频率为112、280和583 Hz的简谐力分别进行叠加,然后以压电陶瓷片作为激振器对平板叶片进行激励,同时以压电陶瓷片作为感应器采集位移响应,最后应用谱分析方法对位移响应进行分析。通过对比不同频率的激振力叠加作用下的位移响应自功率谱幅值,发现自功率谱幅值比单一频率激振力作用时有所降低,并且降低的程度和与其叠加的激振力频率的大小和个数有关,叠加的个数越多,降低的程度越大。 相似文献
5.
课题基于UG软件对某两轮摩托车车架进行了几何建模,并经适当简化导入ANSYS软件进行自由振动(free vibration)分析与调和振动(harmonic vibration)分析。根据分析结果可以看出受迫振动的振幅表现与自然频率的共振现象,产生明显大振幅的低频率为20 Hz和50 Hz,此频率可视为路况所产生的频率,调和振动分析的共振与自由振动相吻合。比较车架不同位置,把手是最容易被振动的部位。 相似文献
6.
This paper proposes a new numerical simulation method for analyzing the parametric vibration of stay cables based on the theory of nonlinear dynamic response of structures under the asynchronous support excitation. The effects of important parameters related to parametric vibration of cables, i.e., characteristics of structure, excitation frequency, excitation amplitude, damping effect of the air and the viscous damping coefficient of the cables, were investigated by using the proposed method for the cables with significant length difference as examples. The analysis results show that nonlinear finite element method is a powerful technique in analyzing the parametric vibration of cables, the behavior of parametric vibration of the two cables with different Irvine parameters has similar properties, the amplitudes of parametric vibration of cables are related to the frequency and amplitude of harmonic support excitations and the effect of distributed viscous damping on parametric vibration of the cables is very small. 相似文献
7.
A practical suspen-dome project, Changzhou Gym roof, is adopted as an example and its transient analysis based on the multi-support excitations of the earthquake wave is carried out. Compared with the single support excitation, the position and value of the maximum stress under multi-support excitations both change and the amount of elements with obvious changes is large and more than 70% of the total. Moreover, when other terms are not changed, this influence will decrease as the span decreases, but increa... 相似文献
8.
A novel sound quality simulation approach was proposed to optimize the acoustic performance of a four-cylinder diesel engine. Finite element analysis, single-input and multiple-output technology, flexible multi-body dynamics, and boundary element codes were used to acquire the hexahedron-element model, experimental modal frequencies, vibration velocities, and structurally radiated noise of the block, respectively. The simulated modal frequencies and vibration velocities agreed well with the experimental data, which validated the finite-element block. The acoustic response showed that considerable acoustic power levels existed in 1500–1900 Hz and 2300–2800 Hz as the main frequency ranges to optimize the block acoustics. Then, the optimal block is determined in accordance with the novel approach, which reduces the overall value, high-frequency amplitudes, and peak values of acoustic power; thus, the loudness, sharpness, and roughness decline to make the sound quieter, lower-pitched, and smoother, respectively. Finally, the optimal block was cast and bench-tested. The results reveal that the sound quality of the optimal-block engine is substantially improved as numerically expected, which verifies the effectiveness of the research approach. 相似文献
9.
In this study, we report an analysis of cylinder head vibration signals at a steady engine speed using short-time Fourier
transform (STFT). Three popular time-frequency analysis techniques, i.e., STFT, analytic wavelet transform (AWT) and S transform
(ST), have been examined. AWT and ST are often applied in engine signal analyses. In particular, an AWT expression in terms
of the quality factor Q and an analytical relationship between ST and AWT have been derived. The time-frequency resolution of a Gaussian function
windowed STFT was studied via numerical simulation. Based on the simulation, the empirical limits for the lowest distinguishable
frequency as well as the time and frequency resolutions were determined. These can provide insights for window width selection,
spectrogram interpretation and artifact identification. Gaussian function windowed STFTs were applied to some cylinder head
vibration signals. The spectrograms of the same signals from ST and AWT were also determined for comparison. The results indicate
that the uniform resolution feature of STFT is not necessarily a disadvantage for time-frequency analysis of vibration signals
when the engine is in stationary state because it can more accurately localize the frequency components excited by transient
excitations without much loss of time resolution. 相似文献
10.
IMRE HORVÁTH JOŽE DUHOVNIK PAUL XIROUCHAKIS 《European Journal of Engineering Education》2003,28(1):83-102
This paper reports on and draws conclusions about the international course called European Global Product Realization. It was organized to provide university students with knowledge about distributed product development in virtual enterprises. The philosophy of the course is discussed together with its structure, contents, organization, infrastructure, deliverables and the experiences. Necessitated by globalization, the principles of operation of virtual enterprises were used in organizing the course. The knowledge accumulated in global product realization by the participating companies and academic sections provided the basis for the course and for the student projects. The organizers put the students of three European universities into the position of evolving young professionals who act as both knowledge producers and knowledge consumers. The design and engineering students took part in academic lectures and industrial case studies in a virtual classroom and practised collaborative product development in the emulated virtual enterprise. The academic virtual enterprise framework has been confirmed to be a solution for opening the conventional educational institutions. Our future work will concentrate on how to exploit disciplinary and operational research as the engine behind academic learning and teaching. 相似文献
11.
Three-dimensional transient numerical simulation for gas exchange process in a four-stroke motorcycle engine 总被引：3，自引：0，他引：3
INTRODUCTION In-cylinder flow characteristics during fuel in-jection and subsequent interactions with fuel sprays and combustion are important effect on engine per-formance and exhaust emissions of an engine(Floch et al.,1998;Kim et al.,1999).Four key parameters control the flow field in an engine:the mean flow components,the stability of the mean flow,the tem-poral turbulence evolution during the intake and compression strokes,and the mean velocity near the spark gap at the time of ignit… 相似文献
12.
INTRODUCTIONAlthoughmanyeffortsweremadeoverthepastdecadestounderstandthedynamicbehaviorofcable-stayedbridges(WilsonandGravelle,1991),verylittlehasbeenreportedintheliteratureabouttheirseismicresponse-controlanalysis.Eveninthosestudiesreported,onlyuniformearthquakemotionwasassumedalongtheentirebridge(NiandSpencer,2000;Jungetal.,2001;Yozo,2002).Thisassumption,however,maybeunrealisticforlongspanbridgessincethedifferencesingroundmotionamongdifferentsupportsduetotravelingseismicwavesmayresult… 相似文献
13.
This paper presents a semi-active strategy for seismic protection of a benchmark cable-stayed bridge with consideration of multiple-support excitations. In this control strategy, Magnetorheological (MR) dampers are proposed as control devices, a LQG-clipped-optimal control algorithm is employed. An active control strategy, shown in previous researches to perform well at controlling the benchmark bridge when uniform earthquake motion was assumed, is also used in this study to control this benchmark bridge with consideration of multiple-support excitations. The performance of active control system is compared to that of the presented semi-active control strategy. Because the MR fluid damper is a controllable energy- dissipation device that cannot add mechanical energy to the structural system, the proposed control strategy is fail-safe in that bounded-input, bounded-output stability of the controlled structure is guaranteed. The numerical results demonstrated that the performance of the presented control design is nearly the same as that of the active control system; and that the MR dampers can effectively be used to control seismically excited cable-stayed bridges with multiple-support excitations. 相似文献
14.
提出了基于虚拟零力矩点FZMP的在线仿人机器人稳定行走控制方法,以机械系统动力学分析软件ADAMS为基础,建立仿人机器人虚拟样机模型.开发了用于仿人机器人行走仿真的平台,实现了仿人机器人参数化建模,完成了基于虚拟样机技术的仿真. 相似文献
15.
舒红宇 《重庆大学学报(英文版)》2003,2(1)
1. Introduction Transmissions which consist of many different and complicate components as clutches, gearboxes, transversal shafts, etc., are a very important part of automobiles. The torsional vibrations in transmissions affect directly their performances. Many researchers have studied the free and periodic torsional vibrations, the noise and the nonlinear in automobile transmissions [1, 2] etc., considering only the excitation of engine. But the random torsional vibrations excited by road pr… 相似文献
16.
为电网分析、计算提供准确的BPA标准发电机励磁系统模型参数,文章在Matlab环境下建立发电机励磁系统标准模型,以现场试验数据为基础,对模型参数进行辨识并确定其模型参数。随后,通过BPA软件进行空载阶跃响应校核以及负载阶跃响应校核,结果与现场实测波形基本一致,从而认为辨识得到的BPA标准模型参数是正确和有效的。 相似文献
17.
Thelevel of vibration and noiseis animportant estima-tionindexoninternal combustionengines .As vibrationandnoise legislations are continually introduced and progres-sivelyrestricted,lowerlevel noise becomesincreasinglyim-portant .The traditional design pe… 相似文献
18.
对研究生实践教学环节进行了思考,明确了研究生实验教学的目标和要求.结合我校新一轮研究生培养方案的修订,对线性系统理论课程设计了多层次循序渐进的配套课内实践环节,引入虚拟实验和基于dSPACE的控制系统快速原型设计与硬件在回路实验等先进实验手段,提高学员的理论分析能力、工程实践能力和创新能力. 相似文献
19.
潘金坤 《中国现代教育装备》2011,(21):23-25
将虚拟样机技术引入机械设计综合实践课程设计中,以插床机械系统为例,利用ADAMS软件建立导杆机构的参数化模型,并对模型进行运动、动力学仿真及优化设计;用ADAMS软件进行课程设计精确、快捷、方便、直观,课程设计达到了满意的效果。 相似文献
20.
分析了电除尘侧面式振打装置结构特点,利用Solidworks快速建立机械零件的三维实体绘图和三维装配功能,对侧部挠臂锤振打装置的各个组成部分进行实体造型设计与虚拟装配.虚拟设计技术的应用极大地缩短了电除尘侧面式振打装置的设计研发周期,降低了产品生产成本,为电除尘侧面式振打装置的设计提供了一个高效的开发途径. 相似文献