Effect of Hydroxy Gas Addition in Gasoline-ethanol Fuel Mixture on Performance of Spark Ignition Engine

Abstract

Fossil fuel continues as primary energy source for the transportation industry, particularly for the fuel used in spark ignition (SI) engines. The use of biofuels such as bioethanol is a solution to the reliance on fossil fuels to reduce green-house gas emissions in the atmosphere and improve environmental air quality. However, the use of bioethanol as a fuel for the SI engine has limitations, such as a reduction in power produced as compared to pure gasoline due to the low energy input contained by bioethanol compared to gasoline. The objective of this study is to improve the energy conversion efficiency of the SI engine by adding Hydroxy (HHO) from water electrolysis to the gasoline-bioethanol mixture, allowing for increasing application of bioethanol at higher concentrations as an additive in future. The test was performed on a 155 cc SI engine equipped with an Engine Control Unit (ECU) to control the fuel injection. The pressure, temperature, oxygen, and throttle position sensors located on the engine and connected to a NI-MyRIO microcontroller. The injection duration of HHO gas based on the duration of gasoline fuel injection, both of fuel are injected through each injector at the intake manifold. The result shows the characteristics of HHO gas improved the disadvantages of biofuels, which have a lower heating value and higher flame speed of bioethanol and gasoline fuel. The presence of HHO gas into the bioethanol-gasoline blend affected to increase the produced power, torque and thermal efficiency of the SI engine. An increase in thermal efficiency at 9.16% obtained at concentration of 20% bioethanol and HHO.