共查询到15条相似文献,搜索用时 78 毫秒
1.
2.
3.
4.
汽车动力总成的惯性参数(转动惯量和惯性积)通常采用实验方法进行测量,测量误差一般不超过3 %。动力总成悬置系统的固有特性与动力总成惯性参数、悬置刚度、位置、角度密切相关,从而悬置系统的固有频率和解耦率的理论设计值与其真实值之间必然存在一定程度偏差。采用均匀分布随机变量描述惯性参数,以悬置刚度为优化设计变量,提出稳健优化模型对某轿车悬置系统固有特性进行稳健优化。优化结果表明,与确定性优化方法相比,稳健优化方法可以较大幅度地提高频率、解耦率、频率间隔的稳健性。 相似文献
5.
6.
某款2.0TGDI+6AMT汽油机动力总成进行台架试验过程中在不同工况下产生异常振动。针对异常振动问题,通过NVH试验对故障现象进行数据分析,结果表明:动力总成在5/6档发生87 Hz的弹性体模态共振;在2档出现了10 Hz的刚体模态共振。结合测试分析结果,通过改进传动轴连接方式提高动力总成弹性体模态,同时调整后悬置刚度改变刚体模态,从而解决该动力总成异常振动问题。最后,试验测试也证明该分析数据的正确性和优化方案的可行性。此实验分析方法不仅缩短了动力总成的开发周期,而且对解决同类工程问题也具有很好的参考价值。 相似文献
7.
8.
9.
首先对动力总成悬置的理想动特性进行了阐述,分析了橡胶悬置、液压悬置的动特性,比较两者的隔振特性.其次,对半主动和主动控制式悬置结构及工作原理进行了描述.最后,提出了应用CAD技术进行悬置的前期优化设计. 相似文献
10.
11.
以一轿车动力总成惯性通道型液阻悬置为研究对象,讨论了线性与非线性集总参数模型和模型中物理参数的特点及应用范围;应用流体力学有限元分析的方法,计算得到了惯性通道两端压力差与其中液体流动流量的关系,设计并制作了实验台,对计算结果进行了验证.利用惯性通道中液体流动的动量方程和惯性通道两端的压力差与其流量的关系,采用最小二乘方法,得到了惯性通道中液体流动的阻尼参数.该方法得到的阻尼参数,在较大激振频率和激振振幅范围内反应了惯性通道的阻尼特性.利用非线性的集总参数模型和本文方法得到的惯性通道阻尼特性参数,对一液阻悬置的动态特性进行了计算分析,计算结果和实验结果具有较好的一致性. 相似文献
12.
Limitations for the accuracy and reliability of measurements in dilatometers that arise during processing of large amounts
of visual information are analyzed. Possible sources of measurement error for phase shift in the interference pattern during
a study of thermal expansion of a specimen and methods for providing continuous monitoring of quality and increasing the reliability
of measurement results are considered.
__________
Translated from Izmeritel’naya Tekhnika, No. 4. pp. 18–22, April, 2007. 相似文献
13.
One of the main problems in the design of complex Al–Si cast components is the wide variety of mechanical properties in different regions of the castings which is due to the wide range of solidification microstructures, related to the local solidification conditions. There are many papers available on the widely used A356/A357 Al–Si–Mg alloys, however, most experimental data on their tensile or fatigue properties are generally obtained from specimens cast separately or produced under controlled laboratory conditions, that are extremely different from those of industrially cast components. Moreover, most of these data often relate the mechanical properties to only one microstructural parameter, such as solidification defects or secondary dendrite arm spacing, and do not take their simultaneous effect into consideration. For all these reasons, the main problem, in the design phase, is the lack of knowledge of the true local mechanical properties in complex-shaped castings, which often means a conservative approach is necessary, with a consequent increase in thickness and therefore in weight. The aim of this research was to study a complex A356 gravity die cast cylinder head, in order to verify the range of variability of the main microstructural parameters and tensile properties, using specimens directly machined from the casting. The component was heat treated at the T6 condition, and the effect of the delay between quenching and aging on the alloy hardness was also evaluated. Simple experimental equations have been proposed, able to successfully predict the local tensile properties in the casting, when only the most important microstructural parameters and alloy hardness are known. These equations allow the designer to predict the local tensile behaviour without any tensile tests; moreover they can also link the post-processing results of the casting simulation software to the pre-processing phase of the structural ones, with an approach of co-engineered design. 相似文献
14.
15.
目的 当前人工智能生成内容技术(AIGC)已步入全方位商业化阶段,AIGC正在成为智能设计的核心支持手段。为提高设计效率和设计质量,顺应人工智能时代不断变化的复杂设计需求,对AIGC支持下的智能设计方法进行综述。方法 通过文献研究,对AIGC技术的基本原理和主要特点进行深入分析,归纳出基于数据挖掘与分析、知识推理与学习、算法演化与模拟的智能设计方法,并得出数据预处理、语境感知调谐、跨模态交互设计、模型构建与评估、动态化学习与反馈优化等AIGC支持下智能设计的关键步骤。结果 AIGC在工业设计流程迭代、传媒创作人机深度融合和娱乐交互方式研发等领域对智能设计方法的变革具有重大意义。结论 对AIGC技术支持下的智能设计方法进行展望,得出虚实结合下的智能化数字孪生设计、全球协同下的智能设计社会变革、隐私安全需求下的交互反馈模式设计3个方面的趋势。 相似文献