Development Of A Test Method For Automotive Air-conditioning Filters

The rapid development of urbanization in China results in the city's growing number of motor vehicles, which leads to increasingly serious air pollution. In order to reduce the particle exposure to the drivers, more and more air-conditioning systems of automobile install the air filters, which can effectively filtrate the dusts, pollens and car exhaust particles into the cabin so that the passengers feel more comfortable. In this study, the evaluation methods and testing standards for automotive air-conditioning filters will be researched, which can be used in the process of production and users'choice.By single fiber model, influencing factors of filtration efficiency of automotive air-conditioning filters are analyzed. The result of calculation indicates that the most penetrating particle size of automotive air-conditioning filters is approximate at 0.4 micrometer, which can give some advice for the classification of automotive air-conditioning filters.A test system is established according to ISO/TS11155-1 by which automotive air-conditioning filters counting efficiency by particle size can be geted. It also can be used to measure the counting efficiency by particle size under different dust-loading quantity, and then evaluate the filtration performance during the whole life cycle by the counting efficiency. This test system is a computer-centered and high automatic data sample and analyzing system, with friendly user interface by Visual Basic 6.0 programming language. User can choose to either measure the initial efficiency only or measure the average efficiency during the whole life cycle according to their requirement. The accuracy and test error of the system are analyzed. Some experiments are carried out on this test system, for example, the effect of the type of dust,charged aerosols and charged filters on the filtration efficiency of filters are researched. Besides, automotive air-conditioning filters'filtration efficiency under different dust loading quantity is measured and it is supposed to be useful in the research of testing method for automotive air-conditioning filters.The accomplishment of this test system provides manufactures a good tool to ensure the quality of their products, and should provide some ideas and directions for the design of test system for the automotive air-conditioning filters'performance in the future.