Modeling of plasma combustion ignition on an electromagnetic wave driven metasurface

Abstract

We present a multi-physics model of combustion ignition phenomena in an atmospheric pressure hydrogen-air mixture ignited by a microwave surface plasma discharge. The surface plasma is generated over a resonant metasurface structure that provides sufficient field intensification to break down and sustain a discharge. Specifically, a surface electromagnetic (EM) wave mode known as the spoof surface plasmon polariton (SSPP) is excited to yield a hybrid resonance that results from coupling of cavity and surface EM wave modes. Motivated by the need for a large, volumetric ignition kernel for applications in combustion ignition, we numerically demonstrate the volumetric surface plasma discharge enabled by the use of this particular EM wave mode in a high pressure operating regime. We discuss the transient evolution of a centimeter scale plasma kernel and subsequent ignition kernel formation. High density combustion enhancing radical species (O, H, OH) are produced throughout the bulk plasma, which leads to successful ignition. A parametric study shows that the large size of a plasma kernel is attributed to the shortening of ignition delay.