Flame kernel growth study of spark ignited hydrogen air premixed combustion at engine conditions. (1st March 2021)

• Record Type: Journal Article
• Authors: Kumar, Punit; Anil Kishan, P.; Nikhil Mathew, M.; Dhar, Atul
• Is Part Of: Thermal science and engineering progress. Volume 21(2021)
• Publication Date: 2021-03-01
• Subjects: Hydrogen -- Combustion -- Flame velocity -- Stretch rate -- Radical concentration; Heat engineering -- Periodicals; Heat engineering; Thermodynamics; Periodicals; 621.402
• DOI: 10.1016/j.tsep.2020.100769
• Languages: English
• ISSNs: 2451-9049

Abstract

Highlights: Experimental investigation of ignition behavior of H2 -Air mixture. Flame kernel growth was measured for relative air fuel ratio range of 0.8 to 1.4. Flame kernel growth was measured for initial mixture temperature of 303, 363, 423 K. Heat release rate is maximum for stoichiometric mixture and rapidly reduces for leaner mixtures. Abstract: In this study, the spark ignition of H2 -air mixture was investigated experimentally in a constant volume combustion chamber and numerically at initial pressure of 3 bar. The relative air fuel ratio was varied from 0.8 to 1.4 and initial temperature was varied from 303 to 423 K. The flame propagation velocity and pressure rise were recorded. The flame kernel images were processed to get the stretched flame velocity of the mixture. Further the stretched flame velocity was estimated using the unstretched flame velocity and calculating the stretch rate. It was found that the combustion chamber pressure rise is dependent negatively on the initial temperature. With increasing initial temperature, the peak pressure decreases. The stretched and unstretched flame velocities increase with initial temperature and decrease when the mixture becomes leaner due to the change in concentration of free radicals in the combustion chamber.