The influence of the igniter-induced blast wave upon the initial volume and expansion of the flame kernel

Au, S.; Haley, R.; Smy, P. R.

doi:10.1016/0010-2180(92)90006-b

Cited by 17 publications

(3 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many investigators have also performed experimental studies on visualizing spark discharge and ignition using optical and laser techniques. Experiments have been done to visualize the fluid mechanics of the evolving spark and ignition kernels using shadowgraph and schlieren visualization [4,[17][18][19][20][21][22][23][24][25] and interferometry [4,26]. Laser diagnostics, such as laser-induced fluorescence (LIF) [12,23,27] and spectroscopy [23,27], have also been implemented to measure characteristics of the spark kernel such as temperature and magnitude of OH radicals.…”

Section: Introductionmentioning

confidence: 99%

Investigation of the effect of electrode geometry on spark ignition

Bane

Ziegler

Shepherd

2015

Combustion and Flame

View full text Add to dashboard Cite

High-speed schlieren visualization and numerical simulations are used to study the fluid mechanics following a spark discharge and the effect on the ignition process in a hydrogen-air mixture. A two-dimensional axisymmetric model of spark discharge in air and spark ignition was developed using the non-reactive and reactive Navier-Stokes equations including mass and heat diffusion. The numerical method employs structured adaptive mesh refinement software to produce highly-resolved simulations, which is critical for accurate resolution of all the physical scales of the complex fluid mechanics and chemistry. The simulations were performed with three different electrode geometries to investigate the effect of the geometry on the fluid mechanics of the evolving spark kernel and on flame formation. The computational results were compared with high-speed schlieren visualization of spark and ignition kernels. It was shown that the spark channel emits a blast wave that is spherical near the electrode surfaces and cylindrical near the center of the spark gap, and thus is highly influenced by the electrode geometry. The ensuing competition between spherical and cylindrical expansion in the spark $ Full-length article submitted to Combustion and Flame.

show abstract

Section: Introductionmentioning

confidence: 99%

Investigation of the effect of electrode geometry on spark ignition

Bane

Ziegler

Shepherd

2015

Combustion and Flame

View full text Add to dashboard Cite

show abstract

“…The spark initiates a kernel of gas at very high temperature and pressure which then expands outward [9], producing a shock wave that lasts on the order of a few microseconds, which then gives rise to a transient three-dimensional flow field [10]. The flow induced by spark discharges have been the focus of a few computational studies [11]- [13] as well as some experimental investigations, e.g., [14], [15]. Computations on the flow induced by a single spark have thus far been restricted to the very early stages (< 100 µs) of flow development [16].…”

Section: Introductionmentioning

confidence: 99%

Two regime cooling in flow induced by a spark discharge

et al. 2020

View full text Add to dashboard Cite

The cooling process associated with the flow induced by a spark plasma discharge generated between a pair of electrodes is measured using stereoscopic particle image velocimetry (S-PIV) and background oriented schlieren (BOS). Density measurements show that the hot gas kernel initially cools fast by convective cooling, followed by a slower cooling process. The cooling rates during the fast regime range from being 2 to 10 times those in the slower regime. An analytical model is developed to relate the cooling observed in the fast regime from BOS, to the total entrainment of cold ambient fluid per unit volume of the hot gas kernel, measured from S-PIV. The model calculates the cooling ratio to characterize the cooling process and shows that the cooling ratio estimated from the density measurements are in close agreement with those calculated from the entrainment. These measurements represent the first ever quantitative density and velocity measurements of the flow induced by a spark discharge and reveal the role of entrainment on the cooling of the hot gas kernel. These results underscore that convective cooling of the hot gas kernel, in the fast regime, leads to approximately 50% of the cooling and occurs within the first millisecond of the induced flow.

show abstract

“…The motivation for this work is twofold. First, lean combustion in spark ignition and gas turbine engines is desirable for improved efficiency and decreased pollutant formation [1][2][3][4][5][6] . Lean fuel conditions, however, can be more difficult to consistently ignite 7 .…”

mentioning

confidence: 99%

Trajectory, Development, and Temperature of Spark Kernels Exiting into Quiescent Air (Preprint)

Kiel¹,

Blunck²

2012

View full text Add to dashboard Cite

The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS.

show abstract

The influence of the igniter-induced blast wave upon the initial volume and expansion of the flame kernel

Cited by 17 publications

References 7 publications

Investigation of the effect of electrode geometry on spark ignition

Investigation of the effect of electrode geometry on spark ignition

Two regime cooling in flow induced by a spark discharge

Trajectory, Development, and Temperature of Spark Kernels Exiting into Quiescent Air (Preprint)

Contact Info

Product

Resources

About