The Influence of Injection Strategy and Glow Plug Temperature on Cycle by Cycle Stability Under Cold Idling Conditions for a Low Compression Ratio, HPCR Diesel Engine

CFD Investigation on the Influence of In-Cylinder Mixture Distribution from Multiple Pilot Injections on Cold Idle Behaviour of a Light Duty Diesel Engine

“…Various studies [1,2,3,5,6,7,8] have concluded that cold start performance can be greatly assisted by the introduction of a pilot injection, promoting cool flame reactions creating an activated environment in which to inject the main. To examine why extra pilot injections have a positive impact on heat release characteristics in-cylinder fuel distribution has been investigated using Kiva3v.…”

“…Han et al [1] correlated poor start-ability with misfiring cycles and developed a new strategy for diesel engine cold start to minimise misfire. McGhee et al [2] pointed out the importance of an optimised injection strategy at cold idle conditions for low compression ratio HPCR diesel engines. Findings reported by Pacaud et al [3] and MacMillan et al [4,5] have highlighted the importance for further work to investigate cause of poor cold idle stability and the development of suitable techniques to make improvements.…”

The initiation and development of combustion under cold idling conditions using a glow plug in diesel engines

“…The single-cylinder engine and test facility have been used in previous investigations of cold start and cold idling behaviour. 1,2,6,22 The engine has a swept volume of 550 cm 3 and a geometric compression ratio of 15.5:1. Carcal 740-B5-A diesel fuel was used in the engine tests and the optical studies, and the properties are given in Table 1.…”

“…To this end, the GP was powered on and the engine was motored for 15 engine cycles before enabling fuel injection. These initial cycles allowed a target speed 1 In this study, engine tests were carried out using a fixed injection strategy to show the influence of the GP on net heat release and IMEP at three test temperatures (3°C, 6°C and 9°C.) These straddle the 6°C value below which the use of the GP is necessary if early firing cycles are to be achieved while the range is narrow enough to allow the same fuel injection strategy to be used across the set of tests.…”

“…High-speed, direct injection (DI) diesel engines with common rail fuel injection systems are widely used in light duty automotive applications for reasons which include good fuel economy and low CO 2 emissions. Improving engine cold start and the early seconds of warm-up continues to attract attention, especially for low ambient temperature conditions at which potential problems include poor cycle-by-cycle combustion stability, 1,2 increased exhaust emissions including HC, CO and PM, [3][4][5] long cranking periods and noise. These can be exacerbated by the use of lower compression ratios 6,7 for light duty engines in recent years to improve the NO x /PM trade-off at part load and achieve higher specific torque and power at full load using higher boost pressures.…”