龚春忠，单承标，李鹏，苑术平，肖岩

摘  要：本文阐述了减速法测试车辆机械阻力的基本原理。相对于行业普遍使用的减速法机械阻力测试标准，本文改进工作主要如下：二次项阻力系数使用经验值0.035N/（km/h）2，并论证了使用该值的合理性;采用匀加减速车辆机械旋转部件转动惯量，并分析了惯量偏差对试验结果的影响;阻力拟合值作为初值，采用单纯形法进一步寻优获得常数项阻力系数与一次项阻力系数;预热前后各测量5次试验，获得各次阻力测试结果，使用中国工况下百公里机械能耗表示机械阻力大小。改进后的减速法操作简便、精确稳定，在整车经济性开发验证中有重要应用。

关键词：减速法;车辆机械阻力;底盘测功机;旋转惯量

中图分类号：U467.1+2      文献标识码：J      文章编号：1005-2550（2021）05-0053-06

Experimental Study On Mechanical Resistance Of Vehicles By Deceleration Method

GONG Chun-zhong1，2， SHAN Chen-biao3， LI Peng1， YUAN Su-ping1， XIAO Yan1

（1.Hozon New Energy Automobile Co.， Ltd.， Jiaxing， 314000， China;

2.College of engineers， Zhejiang University，  Hangzhou 310000， China;

3.Qingdao automobile Research Institute of Jilin University， Qingdao 266000， China）

Abstract： This paper describes the basic principle of the deceleration method for measuring the mechanical resistance of vehicles. Compared with the commonly used mechanical resistance test standard of deceleration method in the industry， the main improvements in this paper are as follows： the empirical value of the second term resistance coefficient is 0.035n / （km / h）2， and the rationality of using this value is demonstrated; the moment of inertia of the mechanical rotating parts of vehicles with uniform acceleration and deceleration is adopted， and the influence of the inertia deviation on the test results is analyzed; the resistance fitting value is taken as the initial value， and the simplex is adopted The constant term resistance coefficient and the primary term resistance coefficient are obtained by further optimization. The resistance test results are obtained by measuring 5 times before and after preheating. The mechanical energy consumption of 100 km under Chinese working condition is used to express the mechanical resistance. The improved deceleration method is easy to operate， accurate and stable， and has an important application in the development and verification of vehicle economy.

車辆道路阻力是影响车辆经济性的重要因素，行业内普遍认可实际道路滑行试验获得的结果。但由于各阻力的耦合性[1]，以及实际道路试验受环境影响[2]，使实际道路滑行法获得的结果稳定性较差，各影响因素对整车的阻力影响难以通过滑行试验辨识。车辆的空气阻力优化方案通常使用整车动力学风洞试验获得，车辆的机械阻力则选择使用底盘测功机中的等速法或减速法获得[3]。本文基于国标减速法的基础上进行惯量确定、二次阻力设定、数据处理方法、预热问题与测试稳定性等问题进行分析与改进。在实际应用中以车辆制动卡钳影响测试作为实例，并设计新的试验方法，可在道路滑行试验中较有效地解耦车辆空气阻力。……