基于51单片机的热膜式气体流量计校准系统设计  

Design of a Calibration System for Thermal Type Gas Mass Flowmeter Based on 51 Series Single Chip Computer

作　　者：李鸿博 王权 Li Hong-bo;Wang Quan(Shanghai Motor Vehicle Inspection Certification&Tech Innovation Center Co.,Ltd.,Shanghai 201805,China)

机构地区：[1]上海机动车检测认证技术研究中心有限公司,上海201800

出　　处：《内燃机与配件》2024年第21期15-18,共4页Internal Combustion Engine & Parts

摘　　要：热膜式空气流量计长时间使用受气体杂质附着探头和水汽冷凝的影响,流量读数出现误差大的问题,特别是进口热膜式气体流量计,目前国内没有相应的校准能力。针对使用这类气体流量计的发动机试验台架,结合流量测量的响应性要求,提出了以8051系列单片机为核心基于非线性拟合方法的空气流量计校准系统设计方案,可以实现对在用超差空气流量计的校准。通过测试,经校准系统校准后的气体流量相对误差可以控制在±1%以内,满足HJ 1014-2020《非道路柴油移动机械污染物排放控制技术要求》的相对误差要求。The precision of flow measurement for hot-film air mass flow meters is affected by gas impurities adhering to the probe and water vapor condensation during a long period,resulting in remarkable errors in flow readings.Especially for importation hot-film air mass flow meters,there is no ability of calibration now in China.For the engine test bench using this type of air mass flow meter,integrated with the responsiveness requirements of flow measurement,a calibration system design scheme for air flow meters based on nonlinear fitting method with 8051 series single chip computer as the core is proposed,which can achieve the calibration on the overproof of flow readings concerning in-use air flow meters.Through testing,the relative error of gas flow calibrated by the calibration system can be controlled within±1%,meeting the relative error requirements of HJ 1014-2020 Technical Requirements for Pollutant Emission Control of Non Road Diesel Mobile Machinery.

关 键 词：热膜式气体流量计 单片机 校准系统 AT89C52 

分 类 号：TH814[机械工程—仪器科学与技术]