Experimental Investigation on Natural Gas Injection to Minimize Abnormal Combustion and Methane Slip in the Diesel - Natural Gas Dual Fuel Engine at Low Load

Development of Hybrid CNG/Diesel Dual-Fuel Engine in High Load Condition for Marine Debris Vessel

“…Nevertheless, low load conditions on the operational condition should be avoided due to multiplier consequences for the power plant system, especially when using the dual-fuel engine [32-34], It is reported in another study that low-load engine operation lowers thermal efficiency which implies that the combustion is dominantly incomplete [35], Thus, it increases fuel consumption and leads to higher GHG emissions concentrations. Another study also stated that the methane slip or the unburned hydrocarbon significantly increases in low-load conditions [20], However, many options can be applied to overcome those conditions such as regulating the fuel-energy ratio, applying an injection strategy, or attaching an aftertreatment device. Increasing the diesel fuel mass in low-load conditions increases thermal efficiency and lowers methane emissions [36], Moreover, certain injection strategies such as perfect injection timing, injection duration, and split injection also increase thermal efficiency [37], Also, adding the after-treatment such as exhaust gas recirculation (EGR) can re-combust Kapal: Jurnal Ilmu Pengetahuan dan Teknologi Kelautan, 20 (1) (2023): [75][76][77][78][79][80][81][82][83][84] the methane slip and lowers the unburned methane emissions [8], Besides, this strategy is difficult to adjust if the engine is unpacked with self-response control and it is complicated in the case of the in-field application.…”

“…Thus, an aftertreatment device is quite optional based on the cost even from capital cost or operational cost [9], Another option to reduce GHG emissions is converting or blending the diesel fuel to other alternative fuel for the combustion process [10][11][12], Many alternative fuels have their characteristics on the combustion then affect the emissions produced. The diesel engine can use Kapal: Jurnal Ilmu Pengetahuan dan Teknologi Kelautan, 20 (1) (2023):75-84 bio-diesel, methanol, ammonia, or natural gas as the main fuel in a single or dual-fuel mode. Combined natural gas and diesel fuel as dual-fuel in the diesel engine can be a solution to develop a vessel propulsion system due to an abundant source of natural gas fuel which has a main fuel composition of methane [13-15], Natural gas can be stored as LNG (Liquid Natural Gas) or CNG (Compressed Natural Gas).…”

“…The dual-fuel engine is very attractive on emissions with high engine performance at high load conditions compared with diesel fuel [16], The NOx and PM emissions are reduced significantly on dual-fuel engines than the dedicated diesel engine [17], It leads to producing cleaner combustion and lowers the emissions contribution from the marine vessel to improve the environment. However, the CO and HC emissions need to improve in the dual-fuel engine, both in low and high load conditions [18], Besides, it can be lowered in the engine as mentioned in several studies [18][19][20], The high amount of CO and HC emissions in dual-fuel engines can be reduced with higher diesel fuel substitution [21 j, advancing the diesel injection timing [22], or attaching an after-treatment device to the engine [8], The dual-fuel engine can be used in high load conditions with less modification on the system compared with the dedicated diesel engine. Although, several studies mentioned that the knocking phenomenon should be considered on the high load dual-fuel engine operation [2], However, a proper diesel/natural gas fuel ratio can be attractive for the engine operated in high load conditions with less knocking [23], Most marine vessels avoid engine operation in low-load conditions thus dual-fuel engine is more applicable in high loads condition.…”

Numerical Investigation of the Effect of Biodiesel-Biogas Percentage on Performance Characters and Dual Fuel Engine Emissions as Green Technology on Ship

“…Ignition comes from the compression of biodiesel fuel that is sprayed into the combustion chamber. The use of gas fuel, in this case, is biogas which is expected to reduce emissions because it is cleaner, while biodiesel is expected to be the driving force for the use of alternative energy that can replace the use of liquid fossil fuels for diesel engines [3][4][5][6] The term green shipping refers to the designation of a ship as an environmentally friendly vehicle. Environmentally friendly on ships is currently defined as efforts to reduce greenhouse gases in ship operations and building.…”

Study on Natural Gas/Diesel Dual-fuel Engine Energy Ratio: Effect of Natural Gas Injection Parameters

“…The proper energy ratio of natural gas and diesel fuel enhances the combustion process and emissions [11]. Moreover, engine load conditions may vary the fuel energy ratio of natural gas/diesel to result in high combustion efficiency [12][13][14]. In contrast, it may affect knock at high loads or deteriorate the combustion quality which leads to safe operation and uncontrolled emissions, respectively [11,15].…”