Calculation of the Minimum Ignition Energy based on the ignition delay time

Jens Tarjei Jensen; Nils Erland L. Haugen; Natalia Babkovskaia

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arXiv · 1110.1163

Calculation of the Minimum Ignition Energy based on the ignition delay time

Jens Tarjei Jensen·Nils Erland L. Haugen·Natalia Babkovskaia

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Abstract

The Minimum Ignition Energy (MIE) of an initially Gaussian temperature profile is found both by Direct Numerical Simulations (DNS) and from a new novel model. The model is based on solving the heat diffusion equation in zero dimensions for a Gaussian velocity distribution. The chemistry is taken into account through the ignition delay time, which is required as input to the model. The model results reproduce the DNS results very well for the Hydrogen mixture investigated. Furthermore, the effect of ignition source dimensionality is explored, and it is shown that for compact ignition kernels there is a strong effect on dimensionality. Here, three, two and one dimensional ignition sources represent a spherical kernel, a long spark and an ignition sheet, respectively.

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Jens Tarjei Jensen, Nils Erland L. Haugen, Natalia Babkovskaia. 2011-10-06. Calculation of the Minimum Ignition Energy based on the ignition delay time. https://arxiv.org/abs/1110.1163

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