Assessing the addition of hydrogen and oxygen into the engine's intake air on selected vehicle features

Road transport has a significant effect on air pollution. Therefore, the article focuses on the impact of addition of “oxyhydrogen”, known as HHO, on selected vehicle features. These features, on which this study is focused, include the engine power and torque, composition of the exhaust gases and fuel consumption. There was also an impact of HHO on the value of pre-ignition as well as engine cleaning observed. HHO has been obtained from the generator designed and constructed for the purposes of this article. The measurements were performed under conditions of taking electric energy needed for HHO operation from the vehicle used in the measurements and also from the other source. The measurements were performed with vehicles of different kilometres driven, different technical conditions and different fuels and they were conducted under laboratory conditions to ensure a higher accuracy of the results. The results have shown a low impact of HHO addition of 2 dm 3 min −1 on concentration of particular components of the exhaust gases. With HHO added, it was measured a mild decrease in the engine power and torque. Taking electric energy needed for HHO operation from the vehicle used in the measurement has evinced more considerably than addition of HHO into the engine. • HHO addition slightly reduced the engine power and torque. • Taking electric energy for the HHO generator to be driven reduced the power on the wheels. • The fuel consumption at the idling speed with HHO decreased by 10%. • Taking electric energy for the HHO generator to be driven increased the fuel consumption by 20%. • HHO in the amount of 2 dm 3 min −1 is considered very low for a common vehicle.