Numerical simulation of combustion characteristics and emission predictions of methane-air and hydrogen-air mixtures in a constant volume combustion chamber using multi-point laser-induced spark ignition
11 Apr 2021-Energy Sources Part A-recovery Utilization and Environmental Effects (Informa UK Limited)-pp 1-17
TL;DR: A laser is electrodeless with a high energy ignition source and can achieve multi-stage lean-burn combustion using higher spark energy can enhance the combustion characteristics and emission performance as mentioned in this paper.
Abstract: Lean-burn combustion using higher spark energy can enhance the combustion characteristics and emission performance. A laser is electrodeless with a high energy ignition source and can achieve multi...
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01 Jan 2023
TL;DR: In this paper , the laser-induced spark ignition (LISI) of CH4-air mixtures was experimentally studied in a constant volume chamber with a nanosecond pulsed YAG laser of 1064 nm wavelength.
Abstract: The laser-induced spark ignition (LISI) of methane (CH4)-air mixtures were experimentally studied in a constant volume chamber. The experiments were carried with a nanosecond pulsed Nd: YAG laser of 1064 nm wavelength. A piezoelectric pressure transducer coupled to a DAQ system was used for measurement of pressure–time history. The chamber has four diametrically opposite optical windows; two optical windows for laser beam entry and exit and two for optical diagnostics. The experiments were carried out at an initial chamber pressure of 2.5, 5.0, and 7.5 bar and at chamber temperature of 298 K. The minimum pulse energy and breakdown threshold intensity required for breakdown of both pure air and methane goes on decreasing as the initial chamber pressure goes on increasing from 1.0 to 8.0 bar. The pressure–time (p–t) history was recorded for different equivalence ratios (0.6 to 1.4) and at different initial chamber pressure conditions. The peak pressure was observed at ϕ = 1.0 for all initial chamber pressure conditions and as chamber pressure increases from 2.5 to 7.5 bar the peak pressure rises and time to attain peak pressure reduces. The minimum pulse energy needed for burning of methane-air mixture was observed at ϕ = 1.0 and it reduces as chamber pressure increases from 2.5 to 7.5 bar. The analyzed data will be useful to study the behavior of laser ignition of the methane-air mixture and can be useful to develop commercial LISI engines in future.
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