Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.
This study was investigated to examine the potential
increase of engine power through the mixture of di-methyl
ether (DME) and liquefied petroleum gas (LPG) on
homogeneous charge compression ignition (HCCI) combustion.
The effects of mixing ratio of DME/LPG in constant intake
temperature were confirmed experimentally in a single cylinder
diesel engine. A numerical analysis were conducted through the
mixing model of DME and n-Butane for the detailed chemical
kinetics using CHEMKIN-PRO to clarify the autoignition
mechanism of constant combustion phasing. The results show
that the increased amount of LPG reduces the low temperature
heat release (LTHR) and activates the high temperature heat
release (HTHR) which increases the in-cylinder pressure.
Therefore, it has potential to raise the indicated mean effective
pressure (IMEP) by appropriately changing the mixing ratio.
Also, thermal efficiency was increased to 51.2% at the mixing
ratio of 0.6. Finally, engine out emissions including total
hydrocarbon (THC) and carbon monoxide (CO) were decreased
by the change of mixing ratio. Numerical results agreed with
experiment that the weakened low temperature oxidation by the
increase of n-Butane amount.