Nano-Fiber Filters for Automotive Applications

Engines have well lubricated metallic moving parts protected by oil films. Microscopic airborne particles can easily break down the oil film and change the tight working tolerances of operating components of an engine. In addition to the above requirement, a modern diesel engine requires a highly precise injection system to meet stringent emission norms and it requires an average of 15,000 L of air per unit fuel consumed. Meticulous filtration is key to ensure purity of air and fuel available to engine. A Polyacrylonitrile based nanofiber synthesized using electro-spinning process is an alternative to conventional cellulose media filters. A Scanning Electron Microscope image is analyzed to obtain the fiber diameter and a 2-D modeling is done using this image data. The trend of developing miniaturized model in filtration application and analysis using computational fluid dynamics has limited research till now. The objectives of the paper are to analyze variation of pressure drop and quality factor for automotive filtration applications. Pressure drops across the single layer of nano-fiber filter, conventional fuel filter and double layer nano-fiber filter are calculated by Ansys fluent analysis. Electro-spun nanofiber filter can separate large number of particles which is beneficial for the longer lifecycle and higher performance of an engine. A single layer polyacrylonitrile nanofiber filter is found to have minimum pressure drop resulting in higher quality factor for filtration applications. As the number of layers of nanofiber increases the pressure drop observed is higher compared to conventional filter.