Experimental investigation of the use of LPG in a gasoline vehicle with a fuel stratified injection

Abstract

This study is intended to determine the applicability of LPG systems with hybrid LPG technology which could not be applied before in vehicles with layered combustion system. No previous academic studies have been found in the literature on hybrid LPG system. This technology exists in the sector, but an academic gap has been filled with this study. For this purpose, Volkswagen Touran 1.6 FSI brand vehicle, which had a four-stroke, four-cylinder, direct injection, split intake manifold, layered combustion system gasoline engine with AKL brand hybrid LPG system, was used on a dynamometer and vehicle wheel power and exhaust emission values were measured according to DIN 70020 at different gear ranges and speeds. When the power values were examined, it was determined that there was approximately 10.23% power loss in LPG mode compared to gasoline mode. When gasoline and LPG fuels are evaluated in terms of energy values in liter basis use; this may result from the fact that LPG gives 30% less energy than gasoline, and secondly LPG fuel occupies more space because it enters the combustion chamber in gaseous phase with the air in the engine intake manifold. When the exhaust emission values are analyzed, it is seen that 8.25% and 71.76% less harmful emissions occur for CO₂ and CO values in LPG mode compared to gasoline mode. It was also seen that, in HC values, there was 27.15% less emission in 3rd, 4th and 5th gear levels in LPG mode compared to gasoline mode; and there was 14.28% more emission in 6th gear level. When the changes of the lambda (λ) values are examined, it is observed that it occurs at a more ideal rate in the 3rd and 4th gear stages in LPG mode compared to gasoline mode, in the 5th and 6th gear. As a result, it was observed that hybrid LPG system can be applied on gasoline engines with layered combustion system and although there is a loss of power in terms of vehicle performance, it was concluded that the use of LPG was advantageous compared to the use of gasoline fuel regarding exhaust emissions.

Appendix

Below is a sample calculation for engine power using gasoline fuel for 4th gear 100 km/h.

$$ P_{w} = \frac{{F_{w*V} }}{3600}\left( {kW} \right) $$

(14)

Speed, V=100 km/h ± 5

Engine power, P=59 HP=59/1.36 = 43.3823529412 kW

Force, Fw=1561.764706 N ± 0.1

$$ \frac{{\partial {\text{P}}}}{{\partial {\text{F}}}} = \frac{{\text{V}}}{3600} = \frac{100}{{3600}} = 0.0277777778 $$

(15)

$$ \frac{{\partial {\text{P}}}}{{\partial {\text{V}}}} = \frac{{F_{w} }}{3600} = \frac{1561,764706}{{3600}} = 0.433823529 $$

(16)

$$ W_{P} = \sqrt {\left[ {\left( {0,0277777778} \right)^{2} *\left( 5 \right)^{2} + \left( {0,433823529} \right)^{2} *\left( {0,1} \right)^{2} } \right]} $$

(17)

$$ W_{p} = 0,145506536 $$

$$ \% W_{p} = \frac{{W_{p} }}{P}*100 = \frac{0,145506536}{{43,3823529412}}*100 = \% 0.335404896 $$

(18)