【作者】 蔡团结；

【导师】 郭晓汾；

【作者基本信息】 长安大学 ， 载运工具运用工程， 2009， 博士

【摘要】 随着汽车保有量的逐年快速增长,每年由汽车所消耗的燃料也逐年增加。我国目前测量机动车燃油消耗量主要采用燃油流量计测量,而这种油耗检测方法无法对采用新技术燃油供给系统和喷射系统的车辆,以及后扒轮、大型半挂车等的车辆进行检测。因此,有必要研究一套不解体的车辆油耗量的检测方法,在汽车性能检测站进行快速油耗测量,其中的关键技术在于油耗计算模型和行驶工况的模拟,本文就这两方面展开研究工作。从汽车技术性能、车重和空气阻力以及道路环境方面,详细分析了汽车燃油消耗的影响因素,认为车辆自身技术状况除外,道路行驶阻力等环境因素也是考量燃油消耗的重要影响因素；通过燃烧理论分析,建立了汽油机的碳平衡油耗测试模型,并在此基础上推导了应用于柴油机的碳平衡油耗测试模型,并对碳平衡模型中的三个所需计算参数给出了具体测量方法。在分析了汽车行驶阻力形成机制的基础上,分析了三种阻力系数确定的试验方法,确定了本研究采用多车速滑行试验法,并建立了多车速滑行阻力模型。提出了底盘测功机的加载原则,即：①底盘测功机的当量设定值等于车辆基准质量与从动轮的当量惯量之和；②底盘测功机功率吸收单元主要用来模拟汽车在道路上所受到的空气阻力和部分滚动阻力,其值应该等于道路负荷与系统总摩擦损失之差值。通过对7辆客车与6辆拦板货车进行了道路滑行试验,利用多车速滑行法计算出了各车所用轮胎的道路滚动阻力系数以及各自的空气阻力系数。对底盘测功机HYCG-130LD6与HYCG-100E1进行滑行试验,并通过回归分析的方法计算出了两种测功机的台架内阻。用安装不同轮胎的车辆在底盘测功机上进行滑行试验,测出不同型号轮胎的台架滚动阻力系数,并与车辆的道路滚动阻力系数比较,提出了同种型号轮胎的台架滚动阻力系数是其道路滚动阻力系数2倍的结论,并利用该结论对未做道路滑行试验的轮胎的道路滚动阻力系数进行推算。根据轮胎型号及其道路滚动阻力系数的分布规律,得出不同轮胎道路滚动阻力系数的近似取法。对底盘测功机模拟道路行驶阻力的加载力与准确计算得出的加载力进行了比较分析,二者的误差在可以接受的范围内。最后进行了碳平衡法不解体油耗检测试验验证,结果表明,不同底盘测功机加载条件下,等速油耗实测与碳平衡模型值之间相对误差均小于5%,说明本研究基于碳平衡法的底盘测功机加载测试系统具有实用性,可以满足在用车不解体检测油耗的需要。更多还原

【Abstract】 As the number of vehicles possessed is growing rapidly year by year, the fuel consumption of vehicles is also increasing year by year. The fuel flow meter measurement method is mainly used as current fuel consumption measurement of vehicles in China, but this fuel consumption detection method is not fit for fuel supply system and the injection system of vehicles adopting new technology, as well as the large semi-trailer and other vehicles for testing. Therefore, it is necessary to study the fuel consumption detection method of non-disassembly. In the vehicle performance testing station for rapid fuel consumption measurement, the key technology is the fuel consumption calculation model and the simulation of driving conditions, and these two aspects are mainly studied.With aspects of vehicles’technical performance, vehicles’ weight, air resistance and road environment, the influential factors of the vehicle fuel consumption are analyzed in detail and make a conclusion that except for the technical condition of vehicles, the environmental factors such as resistance to the roads are also important to the influential factors of fuel consumption; through the analysis of the combustion theory, the fuel consumption test model of gasoline engine based on carbon balance is established, and on this basis, the test model used in the carbon-neutral diesel fuel is concluded, the three parameters of carbon balance model need to be calculated and the specific measurement method is given.The formation mechanism of resistance of the vehicles is analyzed, and three kinds of test methods for drag coefficient are analyzed. Based on that, the test method of the present study about a multi-speed glide is clarified, and the multi-speed glide resistance model is established. The loading principles of the chassis dynamometer is shown, namely:①the setting of the chassis dynamometer is equal to the equivalent of the base vehicles’quality and the equivalent inertia of wheel driven;②chassis dynamometer power absorption unit is mainly used to simulate the air resistance of vehicles on the road and part of the rolling resistance of vehicles on the road, and its value should be equal to the difference of the road loading and the total friction loss between the system.Through the sliding test of seven buses and six trucks on the road, each vehicle’s tire rolling resistance coefficient and their respective air drag coefficient are calculated using multi-speed slide method. Through the sliding test of chassis dynamometer HYCG-130LD6 and HYCG-100E1, two dynamometers’ rig resistances are calculated by the method of the regression analysis. Vehicles with different tires slide on the chassis dynamometer tests, and different types of tire rolling resistance coefficient are measured. Compared with the vehicle rolling resistance coefficient on the road,that rig rolling resistance coefficient with the same kinds of tires is two times of the rolling resistance coefficient is concluded, and making use of the conclusions, tire rolling resistance coefficient on the road without the road sliding test is calculated. According to the distribution of tire model and road rolling resistance coefficient, the approximate values originates of different tire rolling resistance coefficient are got.The load force that the chassis dynamometer simulates road driving resistance and load force calculated accurately are comparatively analyzed, and the error between them is in the acceptable range.At last, the non-disassembly fuel consumption detection test based on the carbon balance method is verified, and the results show that on the different loading conditions of chassis dynamometer, the relative errors between the values of the constant speed fuel consumption testing method and the values of the carbon balance model testing method were less than 5%. So it shows that the present study based on carbon balance method of chassis dynamometer loading test system is practical, to meet needs of the vehicle inspection without disassembly fuel consumption.更多还原