Vehicle Emission Test System Design And Implement

With the hard air pollution in urban, the more and more attention to vehicle exhaust pollution and controlling has been taken More and more emission test regulation were carried out by our government, which has lower limit value. All the emission regulation test system were imported from out of China and they all shared some serious shortage, for example high price for purchase and daily maintenance, long time for installation and commissioning before the system was ready for real test run. Developing advanced vehicle exhaust test system has important reality significance.Taking the introduced AVL emission test equipment as the development object, this paper sets up a vehicle exhaust host computer system and establishes a distributed computer system as controlling scheme. By serial transmission technology and the AK communication protocol among the emission test equipments. By directed to object original programming technique and visual programming language, the software of host computer system is developed.Research has been done in vehicle emission measurement and analysis technology for dilution constant volume sampling system of vehicle exhaust gas. The delay of emission gas transportation and analysis for components in gas are dealt with. The definition and calculating equation for dilution factor(DF) are given. Based on measuring data during test period, calculation model of transit emissions feature of vehicle and vehicle fuel consumption calculating equation based on carbon-balance are deduced.1) Research and analysis for vehicle emission component principle of generation and testing;2) Using mode cycle test to simulate actual vehicle status instead of idle speed;3) Deeply research for the sampling gas time delay caused by transportation and analysis;4) Combining the automotive test engineering with field PC and modern sensor technology;5) The system implemented by Delphi integration, object oriented tools kit, with rapid response speed and friendly interactive interface.6) High sampling data precision from digital filter;7) Much more convenience for operator because all the information from software system was expressed by Chinese language.