Effects of Exhaust Valve Opening Angle on Energy Distribution&nbsp;of Gasoline Engine with Low Heat Rejection and Atkinson Cycle

LIU Yang; HE Yituan; HAN Cuijie; YUAN Chenheng

doi:10.3969/j.issn.1001-2222.2018.01.003

Vehicle Engine ›› 2018, Vol. 0 ›› Issue (1) : 16-20. DOI: 10.3969/j.issn.1001-2222.2018.01.003

Effects of Exhaust Valve Opening Angle on Energy Distribution of Gasoline Engine with Low Heat Rejection and Atkinson Cycle

LIU Yang,HE Yituan,HAN Cuijie,YUAN Chenheng

Author information +

History +

Abstract

The simulation model of supercharged gasoline engine was built with GTPower software and was verified by the experiment. Atkinson cycle was first achieved by optimizing the valve train of original model through designing the intake cam with a larger angle, multiple exhaust valve open angles between 20°CA and 80°CA were acquired by designing multiple exhaust cams, the condition of low heat rejection in the cylinder was realized by changing the heat transfer model, and the effects of exhaust valve opening angle on engine energy distribution were finally simulated and analyzed under the condition of 1 500 r/min and 40% load. The results show that gasoline engine has better fuel economy at the exhaust valve opening angle between 60°CA and 70°CA under the normal cooling condition and at the angle between 50°CA and 60°CA under the low heat rejection condition. The energy loss owing to heat rejection reduces greatly after decreasing the heat transfer coefficient and hence the indicated work increases. The increased indicated work is different under different exhaust valve opening angles. The indicated thermal efficiency increases by 6.58% when the conversion ratio is 17.4% at the exhaust valve opening angle of 55°CA. However, the indicated thermal efficiency of supercharged gasoline engine with Atkinson cycle is only 3.79% higher than that of original engine under the normal cooling condition, which indicates that combining the technology of low heat rejection and Atkinson cycle can strengthen the effect of energy saving.

Key words

Atkinson cycle / gasoline engine / low heat rejection / exhaust valve opening angle / energy distribution / fuel economy

Cite this article

EndNote

Ris (Procite)

Bibtex

Download Citations

LIU Yang,HE Yituan,HAN Cuijie,YUAN Chenheng. Effects of Exhaust Valve Opening Angle on Energy Distribution of Gasoline Engine with Low Heat Rejection and Atkinson Cycle[J]. Vehicle Engine. 2018, 0(1): 16-20 https://doi.org/10.3969/j.issn.1001-2222.2018.01.003