点燃式甲醇发动机校正净功率测量不确定度评定研究  

Experimental Study on Uncertainty in Measurement of Corrected Net Power from Spark-Ignition Methanol Engines

作　　者：庞永胜 庞国民 吴涛阳 刘吉绪 吴春玲 王凤滨 赵亮 郑子鑫 郭向阳 PANG Yongsheng;PANG Guomin;WU Taoyang;LIU Jixu;WU Chunling;WANG Fengbin;ZHAO Liang;ZHENG Zixin;GUO Xiangyang(CATARC Automotive Test Center(Tianjin)Co.,Ltd.,Tianjin 300300,China)

机构地区：[1]中汽研汽车检验中心(天津)有限公司,天津300300

出　　处：《内燃机》2024年第6期1-8,共8页Internal Combustion Engines

基　　金：国家重点研发计划(2022YFC3703600)。

摘　　要：为了掌握和提高点燃式甲醇发动机校正净功率测量准确度,基于一台6缸甲醇发动机在额定点工况系统研究了校正净功率测量结果的不确定度。建立了校正净功率数学计算模型,并对模型中测量重复性、测功机精度和温度压力测量精度等各影响因素的相对标准不确定度进行了分析与评定,最终得到校正净功率的不确定度评定结果。试验结果显示,发动机额定点工况的校正净功率均值为312.43 kW,合成相对标准不确定度为0.28%,合成标准不确定度为0.8868 kW,扩展不确定度为1.7736 kW。对比分析各影响因素的不确定度,其中扭矩测量对不确定度影响贡献最大。本研究将为点燃式发动机性能的精确测量提供参考。In order to understand and improve the accuracy of corrected net power measurement for spark-ignition methanol engines,an experiment was performed based on a methanol engine to evaluate the uncertainty of corrected net power measurement under the rated condition.The mathematical model of corrected net power was established,and the relative standard uncertainty for each factor(measurement repeatability,accuracy of dynamometer,accuracy of temperature and pressure)was analyzed and evaluated.The evaluation result of uncertainty for corrected net power was obtained.Result shows that the average value of corrected net power under the rated condition is 312.43 kW.The combined relative standard uncertainty is 0.28%and the combined standard uncertainty is 0.8868 kW.The expanded uncertainty is 1.7736 kW.From the uncertainty of various factors,it can be seen that the torque measurement has the greatest effect on the uncertainty.The results will provide reference for the accurate measurement of performance in methanol engines.

关 键 词：点燃式发动机 校正净功率 计算模型 不确定度 影响因素 

分 类 号：U464[机械工程—车辆工程]