Fuel Burning Rate Model for Stratified Charge Engine

A zero-dimensional single-zone double-curve model is presented to predict fuel burning rate in stratified charge engines, and it is integrated with GT-Power to predict the overall performance of the stratified charge engines. The model consists of two exponential functions for calculating the fuel burning rate in different charge zones. The model factors are determined by a non-linear curve fitting technique, based on the experimental data obtained from 30 cases in middle and low loads. The results show good agreement between the measured and calculated cylinder pressures, and the deviation between calculated and measured cylinder pressures is less than 5%. The zero-dimensional single-zone double-curve model is successful in the combustion modeling for stratified charge engines.     

一步逆成形有限元法的叉车机罩坯料轮廓优化

本文运用一步逆成形有限元法,对某型叉车发动机罩成形面进行分析,得出轮廓的尺寸,与经验法得到的轮廓尺寸进行比较,再适当的优化,最后进行生产性验证。本设计使用solidworks三维建模,使用dynaform的BSE模块做坯料分析。说明一步逆求法可以准确的预测毛坯的形状,为冲压件的毛坯形状设计提供依据。     

进气增压技术在两用燃料发动机上的应用设计初探

CNG-汽油两用燃料发动机以天然气为燃料时,由于充气效率下降,致使发动机动力性能下降。基于对两用燃料发动机工作特性的对比研究,提出了在CNG-汽油两用燃料发动机上采用进气增压技术,借助于装在发动机上的专用增压装置,将进八气缸的空气预先压缩以提高缸内的充气密度,从而提高发动机充气效率的有效措施。为保证增压器与发动机良好匹配,通过计算提出了确定增压参数的方法及要点,并设计了整个增压系统在CNG-汽油两用燃料发动机上的布置方案及连接关系。     

浅谈为何会发生发动机怠速不稳定的现象

发动机低速运转不稳定常表现：怠速运转不平稳和所谓的“游车”。     

汽车发动机技术及其新进展

发动机是将某一种形式的能量转换为机械能的机器。其功用是将液体或气体的化学能通过燃烧后转化为热能,再把热能通过膨胀转化为机械能并对外输出动力。汽车的动力来自发动机。发动机是汽车的心脏,为汽车的行走提供动力,汽车的动力性、经济性、环保性。汽车发动机作为汽车的核心部分是一个汽车的灵魂,汽车发动机的好坏直接影响到汽车的价值与功能。本文通过汽车发动机的基本原理和构造、衡量汽车发动机的技术指标、汽车发动机的性能提高和汽车发动机的发展趋势四方面介绍汽车发动机技术及其新进展。     

以平常心看自主创新

第三条路,是眼下南汽人爱用的一个词儿。用南汽名爵总经理张欣的话说,“现在,大家都在喊自主,有的企业自己去研究发动机,自己去白手自主;另     

Effect of a semi electro-mechanical engine valve on performance and emissions in a single cylinder spark ignited engine

In this study, an electro-mechanical valve （EMV） system for the intake valve ofa fottr stroke, single cylinder, overhead valve and spark ignition （SI） engine was designed and constructed. An engine with the EMV system and a standard engine were tested to observe the effects of the EMV on engine performance and emissions at different speeds under full load. The EMV engine showed improved engine power, engine torque and break specific fuel consumption （BSFC）. A 66% decrease in CO emissions was also obtained with the EMV system, but hydrocarbons （HC） and NOx emissions increased by 12% and 13% respectively.     

奋力托举火箭升空 泰然书写华彩人生——记我国著名火箭发动机专家张贵田院士

火箭．是目前唯一能够使物体达到宇宙速度,克服或摆脱地球引力．进入宇宙空间的运载工具。每当看到火箭这种庞然大物拔地而起、腾入宇宙的壮观景象．我们常会惊叹不已——究竟是从何而来的神力托举它飞离地面,进入太空？答案是火箭发动机。