论文标题:汽车动力系统合理匹配研究
A Study to the Optimal Matching of Automobile Driveline
论文作者
论文导师 宋振寰,论文学位 硕士,论文专业 车辆工程
论文单位 大连理工大学,点击次数 827,论文页数 61页File Size2308k
2005-12-06论文网 http://www.lw23.com/lunwen_330116647/
Automobile Driveline; Optimal Matching; Study
评价一辆汽车的性能有很多技术指标,如衡量汽车动力性的指标:最高车速、爬坡性能和加速性能等,衡量燃油经济性的指标:汽车在标准试验循环下的百公里油耗等。但是这些指标都不足以全面衡量一辆汽车的好坏,汽车集动力性与燃油经济性为一体,同时很多指标又互相制约,所以任何割裂开的技术指标仅仅是反映汽车的某一方面,而不是整体性能指标。 现代汽车技术的发展使汽车的动力性和燃油经济性都达到了前所未有的高水准,但是二者之间存在一个合理匹配问题。要想使汽车的动力性好,就应该使汽车能有足够高车速及较强的牵引力,而要想使汽车的燃油经济性好,除了让发动机的燃油消耗率最小,还要求在实际行驶工况时,发动机总是处于燃油消耗率最小的经济区域内。对于某一特定的车辆,当汽车总重、重量分配、轮胎等已确定的情况下要做到这一点,主要依靠发动机与传动系的合理匹配,即合理选择发动机与传动系统各参数使之发挥最佳动力性和燃油经济性。 本文在充分阐述国内国外汽车动力系统匹配诸多研究成果和相关法规体系的基础上,提出一套评价汽车动力匹配的方法,对车辆动力系统的匹配进行量化评价。从汽车发动机数学模型和万有特性数学模型建立入手,运用数值方法和部分优化理论,模拟出汽车动力性和燃油经济性方程式,作为建立评价指标的基本依据。采用多因子加权系数法,建立了汽车动力匹配评价系统。将良好路面的高挡最高车速因子作为汽车动力性的评价指标,高挡常用车速比油耗因子作为汽车燃油经济性的评价指标,汽车能量利用率因子以一个综合指标作为第三个评价指标,将这三个指标进行加权处理,得到一个综合评价方程式,以此度量汽车动力系统具体匹配的优劣。此方法对汽车各种性能指标及公式进行了抽象总结,形成一套简便直观的评价方法,避免了大量繁杂的计算,即平衡了各类指标中的矛盾,又突出了汽车的整体性,具有较强的可操作性。
There are many technical indexes to appraise the performance of an automobile. Such as evaluating the index of an automobile dynamic performance which includes maximum vehicle speed, climbing grade ability and acceleration ability, the index of fuel consumption efficiency which includes the oil consumption per hundred kilometers when the automobile is under standard, testing cycle and so on. But it is insufficient to appraise the performance of an automobile by the indexes mentioned above comprehensively. The performance of an automobile includes dynamic performance and fuel consumption efficiency and the two parts can"t be divided into two separate piece. Meanwhile the two indexes are mutually contradictory. Therefore each separate index only reflects one side of a automobile but not the whole.The development of the modern automobile technology has caused the dynamic performance and the fuel consumption efficiency to achieve the unprecedented high level, but between the two has a reasonable match problem. If we want to get high dynamic performance of an automobile, we should enable the automobile to have a high vehicle speed and a strong force of traction. While we want to get better fuel consumption efficiency , we should not only make the engine"s fuel consumption at the lowest rate, but also make the engine work in the economic region of the lowest fuel consumption rate when the automobile is in its actual driving condition. Regarding a certain specific automobile, the gross weight, the weight assignment, the tire and so on have been determined .In the situation ,if we want to achieve this point, we mainly depend upon the reasonable match between engine and the power transmission. That is to say we should choose various parameters of the engine and the transmission system to cause it display its best dynamic performance and the fuel consumption efficiency.This article introduces many research results and in the correlation laws and regulations system foundation in the full elaboration domestic overseas automobile dynamic system, proposes a set of appraisals automobiles power match method, carries on the quantification appraisal to the vehicles dynamic system match. And ten thousand has the characteristic mathematical model establishment from the motor car engine mathematical model to obtain, the utilization value method and the partial optimized theory, simulate automobile dynamic performance and the fuel consumption efficient equation, takes the establishment appraisal target the basic basis. Uses the multi- factors weighting method of correlates, has establishedthe automobile power match appraisal system. High keeps off the maximum speed factor the good road surface to take the automobile dynamic performance appraisal target, high keeps off the commonly used vehicle speed compared to the oil consumption factor to take the automobile fuel oil efficient appraisal target, the automobile energy use factor by a overall target took the third appraisal target, carries on these three targets weighting processing, obtains a quality synthetic evaluation equation, by this measure automobile dynamic system concrete match fit and unfit quality. This method has carried on the abstract summary to each kind of performance index and the formula of the automobile, forms a set of simple direct-viewing assessment methods, has avoided the massive numerous and diverse computations, namely has balanced in each kind of target contradiction, also has highlighted the automobile integrity and thus has more manipulative feasibility.
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