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基于虚拟样机的摩托赛车发动机动力学性能仿真技术 总被引:4,自引:1,他引:3
基于虚拟样机的机械动力学性能仿真技术是现代机械设计与制造的重要核心技术之一.介绍了利用PTC公司的Pro/E与Pro/MECHANICA软件,能够模拟机器实际工作状态时的运动和动力学特征的摩托赛车发动机虚拟样机的几何及物理建模的方法.介绍了应用有限元法,可使该虚拟样机输出模拟工作状态时所产生的动力学特性,如时变动反力,整机与其零部件的模态特性,振动大小等例子.该方法的优点是以动态的、直观的方法使设计人员了解整机与其零部件的动态特性,并及时发现问题与薄弱环节,改善设计,以确保整机良好的动态特性.还特别介绍了该方法在作者建立的摩托赛车发动机虚拟样机系统等方面的应用.该摩托赛车发动机虚拟样机系统可以进行发动机机构的运动、动力学仿真,可以获得活塞、曲轴上受到的时历动态变载荷.该虚拟样机系统不仅可以对活塞、曲轴与连杆等零件进行考虑到气缸爆炸力、热、惯性力藕合作用时的精确应力应变仿真、还可以对曲轴进行考虑到气缸爆炸力、惯性力作用下的时历响应与频域响应振动仿真.本仿真系统阐明了发动机曲轴振动产生的机理,并提出了降低振动的曲轴设计新方法.应用了该法后,使某新型曲轴的轴径减小了5 mm,并成功通过试车阶段. 相似文献
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活塞敲击是柴油机主要的振动和噪声源,其主要原因是活塞在其与缸套的间隙中做横向和偏摆的二阶运动,因此研究活塞设计参数对活塞二阶运动的影响,优化活塞动力学特性,对于发动机减振降噪具有重要意义。以某非道路四缸高压共轨柴油机为研究对象,建立活塞动力学计算模型以及整机多体动力学计算模型,通过机体和曲轴的模态试验,验证了有限元模型的准确性;采用正交设计方法,研究了活塞销偏置量、活塞裙部中凸点位置、配缸间隙对活塞动力学、整机振动与噪声的影响。研究结果表明:活塞配缸间隙对活塞敲击能量、活塞敲击力、活塞所受力矩影响最大;对发动机振动噪声敏感性分析显示,活塞销偏置是影响发动机振动与噪声性能的关键因素。 相似文献
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为进一步提高发动机燃烧效率,减少发动机有害气体的排放,提出了一种液压式连续可变压缩比技术的设计方案。它是通过液压系统控制偏心销转动来改变上止点的位置,从而使燃烧室体积发生变化,实现在调节区间内任意连续可变压缩比的改变。首先,根据所设计的方案分析了其液压系统在2个不同阶段的调节工作原理;然后,利用三维软件Solidworks2010对整个系统进行三维建模,根据模型设计的具体尺寸,得到连续可变压缩比调节的范围为8.81~22.43;最后分析了不同转速下活塞系统综合力(活塞惯性力和活塞表面气体压力的合力)的变化情况,并通过MATLAB与AMESim对构建的液压系统进行了联合仿真试验,探究了不同转速下活塞系统综合力向上和向下时液压系统的流量特性和压力特性。仿真结果表明:发动机转速在中低速条件下,活塞系统调节响应迅速,具有良好的动态特性,证明该设计具有一定实用性。仿真结果为用于液压容积调节的连续可变压缩比技术的实际应用提供了理论依据,具有重要的实际指导意义。 相似文献
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介绍了CATIA二次开发技术和参数化技术.为提高产品设计效率,以发动机活塞作为研究对象、三维软件CATIA为平台、CAA为开发工具,研究了发动机活塞的参数化建模方法.简要分析发动机活塞的主要结构参数.用CAA和面向对象的程序语言来设计参数化程序,实现活塞的快速建模,使产品设计效率有很大提高. 相似文献
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介绍了利用系统动力学软件ADAMS建立CDV内燃机工作过程曲柄连杆机构动力学仿真分析模型的方法.根据所建立的模型,对CDV车型使用N6A 10FX3APSA内燃机曲柄连杆机构的运动学、动力学特性进行了仿真.通过仿真计算,得到考虑曲柄柔性时的曲轴主轴径、连杆轴颈载荷,活塞、连杆等的惯性力以及内燃机的输出特性,为此,本文提... 相似文献
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This paper presents preliminary experimental test results for a novel truck auxiliary power unit (APU) design consisting of a 1 kWe free-piston Stirling engine and 2 kWt zeolite-water adsorption chiller that is powered via waste heat from the engine's cooling jacket. A prototype system was built and tested to study the interaction dynamics between the Stirling engine and adsorption chiller and to determine the performance of the chiller in extreme ambient temperature conditions. The results show that pulsed thermal loading from the chiller on the engine results in engine power spikes to 110–115% of rated power. An average COP of 0.42 ± 0.06 was achieved for the adsorption chiller. An investigation into mitigating the negative effects of low buffering was also conducted and estimates that a buffer volume of 50 litres is sufficient to minimise the effects. This volume can potentially be achieved through integration with the main truck engine eliminating the need for a supplementary tank. The proposed system has many benefits over existing technologies such as low noise, high reliability and clean emissions without any need for additional exhaust treatment. 相似文献
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联合国欧洲经济委员会UN ECE R51-03噪声法规依据汽车发动机最大净功率差异,将N2、N3类货车细分为总共5个亚分类,并针对不同亚分类制定了不同的车外噪声限值。与欧洲货车产品相比,中国货车产品普遍存在吨位大、轴数多、最大净功率小的典型特征,UN ECE R51-03法规的亚分类方式将导致中国货车产品必须满足更苛刻的车外噪声限值,形成出口认证的技术壁垒。结合大量验证试验结果提出基于最大总质量和轴数的车外噪声限值亚分类方式,并提出中国货车产品达到UN ECE R51-03车外噪声限值要求的技术途径。 相似文献
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M. A. Korzhuev 《Technical Physics Letters》2011,37(2):151-153
It is shown that an internal combustion engine and a thermoelectric generator (TEG) arranged on the exhaust pipe of this engine
come into the conflict of thermal machines that is related to using the same energy resource. The conflict grows with increasing
useful electric power W
e of the TEG, which leads to the limitation of both the maximum TEG output power (W
emax) and the possibility of waste heat recovery in cars. 相似文献
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In the context of growing environmental concerns, hybrid-electric vehicles appear to be one of the most promising technologies for reducing fuel consumption and pollutant emissions. This paper presents a parametric study focused on variations of the size of the powertrain components, and optimization of the power split between the engine and electric motor with respect to fuel consumption. To take into account the ability of the engine to be turned off, and the energy consumed to start the engine, we consider a second state to represent the engine: this state permits to obtain a more realistic engine model than it is usually done. Results are obtained for a prescribed vehicle cycle thanks to a dynamic programming algorithm based on a reduced model, and furnish the optimal power repartition at each time step regarding fuel consumption under constraints on the battery state of charge, and may then be used to determine the best components of a given powertrain. To control the energy sources in real driving conditions, when the future is unknown, a real-time control strategy is used: the Equivalent Consumption Minimization Strategy (ECMS). In this strategy, the battery is being considered as an auxiliary reversible fuel reservoir, using a scaling parameter which can be deduced from dynamic programming results. Offline optimization results and ECMS are compared for a realistic hybrid vehicle application. 相似文献