Investigation of cycle skipping methods in an engine converted to positive ignition natural gas engine

Abstract

In this study, a single cylinder of 1.16 L, naturally aspirated engine was converted to a spark ignition engine, which was a diesel engine operating with natural gas as fuel. By placing electronic throttle, electronic ignition module, gas fuel injectors and proximity sensors on the test engine, the engine has been turned into a positive ignition engine that can work with natural gas as fuel, thanks to the electronic control unit developed by our project team. Then, in the study performed, different cycle skipping strategies were experimentally investigated at a constant engine speed of 1565 rpm, in accordance with the generator operating conditions. Engine performance, emissions (CO, HC, and NOx), and combustion characteristics (cylinder pressure, rate of heat release, etc.) of cycle skipping strategies were experimentally investigated with natural gas as fuel in Normal, 3N1S, 2N1S, and 1N1S engine operating modes. According to the results obtained, specific fuel consumption, CO and HC values improved in all cycle skipping operating conditions, except for NOx, but the best results were obtained in 2N1S operating conditions; it was concluded that the specific fuel consumption, CO and HC values improved by 11.19%, 61.89%, and 65.60%, respectively.

Increase in the Fuel Efficiency of a Diesel Engine by Disconnecting Some of Its Cylinders

“…The works of scientists [10][11][12][13][14][15] deal with complex issues of a more complete additional loading of the cylinders remaining in operation, a decrease in specific and liter fuel consumption, and an increase in fuel efficiency.…”

Simulation analysis of cycle skipping strategy in SI engine fueled with ethanol gasoline mixture

“…Erdal et al investigated the effects of electronically controlled cycle skipping strategy on emissions in a natural gas gasoline engine. They found significant improvements in HC and CO emissions, but an increase in NOx emissio ns [18]. Mohammed et al discovered that NOx HC and CO emissions were reduced as a result of the research conducted at different engine speeds with mixtures of ethanol in the range of 10-40% [19].…”