Effect of exhaust gas recirculation and constant pre-heated air temperature on the homogeneous charge compression ignition combustion engine with diesel and WPPO 20 blend

This article describes an experimental study on fueling the port fuel injection homogeneous charge compression ignition (PFI-HCCI) combustion engine with plastic oil that is generated from waste plastics through the pyrolysis method. The study tested different exhaust gas recirculation (EGR) levels of 0%, 5%, 10%, and 15% using a modified PFI-HCCI computerized 4-stroke, single-cylinder, water-cooled, direct injection Kirloskar diesel engine connected to an eddy current dynamometer. Furthermore, an engine running at 1500 rpm and a constant preheated air temperature (PHAT) of 140°C were assessed. In this experiment, fuel, 20% biodiesel waste plastic pyrolysis oil (WPPO), and continuous PHAT 140°C are used. The testing results show that the cylinder peak pressure and heat release rate for WPPO 20 with 15% EGR were attained at 39.70% and 15.09%, respectively. Additionally, port fuel injection with PHAT and WPPO 20% without EGR is reported to have a 45% higher brake thermal efficiency at full load in comparison to PFI-HCCI Diesel (D100). But when employed at full load with 15% EGR, the WPPO 20 blend also reduced smoke opacity by 30.74% and Oxides of Nitrogen (NOx) emission by 52.17%. On the other hand, compared to the PFI-HCCI (D100), there are higher emissions of carbon monoxide (CO) (22.07%) and unburnt hydrocarbon (UHC) (54.14%) with 15% EGR. Consequently, WPPO can be used for the PFI-HCCI engine. © 2024 The author(s).