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• Liquid EtOH spray with H 2 enrichment combustion were conducted. • Combustion with global equivalence ratio 0.15(67% EtOH/33% H 2) was achieved. • The effects of ignition timing, injection pressure on lean burn were evaluated. • High jet pressure improves ignition stability but causes incomplete combustion. An experimental study was conducted to determine the effects of ignition timings, injection pressures, and hydrogen enrichment on ethanol stratified ultra-lean combustion. The combustion chamber was a constant volume vessel with an injection and ignition system. The ignition and combustion characteristics of ethanol spray with different ignition timings (0–50 ms after start of injection), injection pressures (5, 15, and 25 MPa), and hydrogen premixed equivalence ratios (0.05, 0.1, and 0.2) under ambient temperature 353 K and 1 atm. The direct injection of ethanol and hydrogen enrichment results in an increase in the stable ignition limit to an extremely lean condition: a global equivalence ratio of 0.15 (67% ethanol/33% H 2). Furthermore, the probability of ignition first increased then decreased with the delay in ignition timings; rose with an increase in the injection pressure and hydrogen ratio. However, the delay in ignition timings and high injection pressures resulting in extremely lean zone in the constant volume vessel, which led to incomplete combustion. The addition of hydrogen not only stabilized ignition process but also improved the combustion characteristics. Stable ignition and combustion were achieved at early ignition timing (2–3 ms), moderate injection pressure (15 MPa), and a minimum global equivalence ratio of 0.2 (50% ethanol/ 50% H 2). [ABSTRACT FROM AUTHOR]