Use of phased supply of hydrogen additives for improvement of the ecological characteristics of the Wankel rotary engine

Abstract

The Wankel rotary engine, designed according to Wankel’s scheme, is more adaptable for running on hydrogen fuels than traditional reciprocating engines, possessing lower pre-ignition and backfire probability. Hydrogen additive to main air-fuel mixture helps to decrease incompleteness of combustion in the vicinity of rear rotor apex. Experimental data for Wankel rotary engine VAZ-311 performance on hydrogen blends with hydrocarbon fuel is presented. Researches are performed on partial loads, where hydrogen mass fraction additions to the fuel mixture didn’t exceed 5%. It is shown that for partial loads (20% of full load) and engine speed n= 2000 min−1 5% hydrogen addition by mass yields to 4.2% decrease of brake specific fuel consumption (hydrogen consumption was converted to gasoline consumption computed proportionally to their combustion heats ratio). Amount of unburned hydrocarbons for the conditions mentioned reduces in a factor of 2 and emission of carbon monoxide reduces to 40%.