Development of a Burner-Based Test System to Produce Controllable Particulate Emissions for Evaluation of Gasoline Particulate Filters 2020-01-0389
Gasoline Direct Injection (GDI) engines have been widely adopted by manufacturers in the light-duty market due to their fuel economy benefits. However, several studies have shown that GDI engines have higher levels of particulate matter (PM) emissions relative to Port Fuel Injected (PFI) engines and diesel engines equipped with optimally functioning Diesel Particulate Filters (DPF). With stringent particle number regulations (PN) implemented in both the European Union and China, Gasoline Particulate Filters (GPF) are expected to be widely utilized to control particulate emissions. Currently, evaluating GPF technologies on a vehicle can be challenging due to a limited number of commercially available vehicles that are available, as well as the costs associated with vehicle procurement and evaluations utilizing a chassis dynamometer facility. To address these challenges, a gasoline fueled burner-based technology was retrofitted with unique hardware to replicate the engine-out emissions profiles observed with GDI applications. In the absence of a suitable vehicle, using a burner-based technology can prove to be a cost-efficient solution for rapid screening of various GPFs.
This manuscript details the development of control strategies which enable the system to control PM and PN (including particle size distribution) emissions that have similar physical characteristics consistent with light duty applications equipped with a GDI engine. Burner-out soot mass, solid particulate size and number distribution, and composition (in terms of elemental and organic carbon ratio) were investigated over various operating conditions. Real-time soot mass measurement was performed using an AVL micro-soot sensor. Solid particle number and size measurement was performed using Cambustion’s DMS500 coupled with SwRI’s solid particle sampling system. EC/OC partitioning was performed using a Sunset Laboratory carbon aerosol analyzer. Results from this campaign were compared to emissions from a modern 2.0L GDI engine. Additionally, the impact of three different, commercially available gasoline fuels on burner-out PM/PN emissions was also studied. Development of a versatile burner-based platform along with a comprehensive operating map of burner-out emissions can serve as an invaluable tool for GPF design and development due to its cost effectiveness, high degree of test repeatability, and reduced complexity.
Nishant Thakral, Vinay Premnath, Imad Khalek, Scott Eakle