Effects of Injection Rate Shape on Performance and Emissions of a Diesel Engine Fuelled by Diesel and Biodiesel B20

Abstract

The combustion process in diesel engines is controlled by the injection rate shape. The stricter emission regulations requiring simultaneous reduction of nitrogen oxides and particulate matter imposes intense research and development activity for achieving clean and robust combustion. This work describes the experimental investigation made for calibration of an engine model and the numerical investigation performed to assess the influences of different injection rate shapes on performances of a diesel engine fuelled with diesel and rapeseed biodiesel B20. The engine model was developed with the AVL-BOOST code using the AVL-MCC combustion mode. The model was calibrated for the reference Top-Hat injection rate shape using experimental data registered for maximum brake torque and maximum brake power speed conditions. Other injection rate shapes such as triangular, trapezoidal, and boot having the same area, start, and duration of injection were investigated in terms of combustion characteristics, performance, and pollutant emissions. The link existing between the injection characteristics and the NOx and Soot emissions highlights that, for the optimal rate of injection shape, a simultaneous reduction of NOx and Soot by 11%, respectively 4% for maximum brake torque and by 22%, respectively 7% for maximum brake power, can be obtained using biodiesel B20.

Unveiling the pros and cons: Consequences of biodiesel in shaping the future of engine fuels

“…Technology advanced so quickly that it became an essential power-producing system. The growth of renewable fuels is driven by the growing need for clean, sustainable alternative energy sources and global efforts to meet emissions objectives through the use of fuel-flexible gas turbine technology coupled with nonfossil fuel alternatives regulation using injection rate shaping, have become important in modern times to ensure greater efficiency and clean combustion (Niculae et al 2022). Khan et al (2023) offered a critical analysis of the latest advancements and patterns in the use of clean fuels in aviation, maritime and road transportation, as well as the possibility that these fuels could provide a largely disregarded route to net zero carbon emissions.…”

Thermal effects on Common Rail injection system hydraulic performance

“…The Common Rail (CR) fuel injection apparatus offers great flexibility in terms of number of injection events per engine cycle, dwell-times between shots, and high injection pressure (up to 3000 bar). 4 The designed shape and quantity of every fuel shot affect combustion and engine-out emission control 5 and both design parameters, associated to the injector structure, 6 and physical factors, such as the fuel properties 7 or the ambient conditions, 8 must be taken into account. Fractioning the injection quantity between multiple shots with close-to-zero hydraulic dwell-times according to digital rate shaping strategies, can allow combustion noise to be reduced significantly.…”

A Study on the Injection Rate Characteristics of the Solenoid Common-Rail Injector Under Using a High-Pressure Fuel System

“…Many researchers have investigated the efficiency of optimizing injection rate characteristics in terms of fuel consumption, emissions, and noise [7], [8], [9]. According to a study by A. L. Niculae et al [10], the optimal rate of injection shape (triangular, trapezoidal, and boot) can simultaneously reduce NOx and soot by 11%, respectively 4% for maximum brake torque and by 22%, respectively 7% for maximum brake power using biodiesel B20, injection rate shape type Boot 2. Research by Z. Zhang et al [11], V. Macian et al [12], the shape of the injection rate profile (square, boot, ramp) as well as multiple injection strategies significantly induced the engine combustion and emission processes.…”