Engine air filtration technologies currently used in air induction systems typically utilize pleated paper or felt type air filters. These air filter designs have been used for many years in panels, cylindrical or round (pancake type) type air cleaners. Pleated air filters are specifically designed to be serviceable and hence their performance is inherently limited by vehicle under-hood packaging and manufacturing constraints. Due to these constraints, majority of air cleaner designs are not optimized for engine filtration and air flow management under the hood.
Studies show that use of low performing serviceable aftermarket air filters significantly affect the performance and durability of engine air cleaners [9]. High mileage studies confirm that engine durability, service issues, warranty field returns and customer satisfaction was affected by use of aftermarket filter brands.
Innovative air cleaner designs are required to maximize filtration performance, improve flow management, extend air cleaner service life and improve engine durability. Filtration characteristics of reticulated porous foams were studied and evaluated as a potential solution. Reticulated foam media has a very open structure, which allows it to have a relatively high dust holding capacity (DHC) and capture efficiency. The potential benefits of reticulated foam filters are longer life, competitive cost and flexibility in packaging. A foam filter model was also developed to predict performances of multi-layer reticulated foam filters. Model predictions for a four layer foam filter design have been presented and discussed.
A new Long Life Filtration System was developed for OEM (Original Equipment Manufacturer) applications (2003/2004 Ford Focus Vehicle) and requirements. This new technology uses a unique multi-layered reticulated foam media which does not need servicing or maintenance for the life of the vehicle [150K+ miles]. This technology also provides some unique advantages over the traditional serviceable air induction filters.
Accelerated field evaluations are also presented to support the new Visteon technology using Long Life Filtration System. These studies show the viability and flexibility of multi-layer foam designs.