Experimental Analysis of Heavy Duty CNG Engine Based on Its Aspiration and Fuel System 2021-26-0117

Engine calibration involves the interaction of electronic components with various engine systems like intake system, exhaust system, ignition system, etc. Emissions are the by-products of combustion of fuel and air inside the combustion chamber. After-treatment systems generally take up the responsibility to scrape out harmful emissions from the engines. However, a good engine calibration will focus on emission reduction at source i.e., during the combustion itself. Thus, the intake of air and fuel in proper amount at each engine operating point is crucial for optimized engine performance and minimal emissions. The Intake system is an integral part of any internal combustion engine and it plays an important role to improve its performance and emission. Generally, for a SI engine, maintaining the stoichiometric A/F ratio is a challenging endeavour from an operational standpoint. Engine power, BSFC, torque and harmful emissions are much influenced by geometric aspect of intake manifold and its fuelling distribution system. The role of the intake manifold is the distribution of Air-Fuel mixture uniformly in all cylinders of the SI engine. Two different intake system configurations viz. SPFI (Single Point Fuel Injection) and MPFI (Multi Point Fuel Injection) are evaluated in this paper. In the Multipoint Injection System, one injector per cylinder is provided which injects the fuel in appropriate quantity in the admission valve allowing the fuel and air into the cylinder. This provides individual control on the cylinder which in turn improves the fuel consumption as compared to the Single point fuel injection. This paper is related to experimental comparison of CNG fuel distribution for a SPFI and MPFI system and its merits and demerits after analyzing the effects on the engine performance and emissions, which were evaluated on the similar engine configurations with SPFI and MPFI fuel distribution systems.