Gravity Effect on Electrical Field Generation and Charge Carriers Transfer During Combustion Synthesis of Sulfides

Abstract

11 The effect of gravity on the electric potential generated by the combustion synthesis of zinc sulfide is analyzed using the 12 numerical simulation. Recent experimental studies on generation of electric voltage during combustion synthesis of zinc 13 sulfide (ZnS) have revealed high voltage signals (4 V) with duration about 1 s, which are much higher than those produced by 14 the gas–solid and solid–solid combustion reactions studied previously. These data have raised the question about mechanism 15 of such a phenomenon. In our previous work we developed a novel (distributed) model describing the electric potential 16 generation during combustion synthesis of sulfides (CSS) that didn't count the effect of gravity. In this paper the simulations 17 of heat -mass transfer, charge carriers motion, and voltage profiles taking into account the Earth gravity effect. The 18 simulations confirms that the gravitation force strongly affects the emission of negatively charged sulfur ions as well as 19 electrons and has a significant impact on the amplitude and temporal evolution of the combustion induced voltage. The 20 voltage reduction up to four times has been observed numerically in the case when gravity acts in the direction coincident to 21 that of the propagating combustion wave. Vice versa, the significant acceleration of the combustion and the voltage 22 amplification due to the advection is simulated when gravity acts in the direction opposite to that of the propagating 23 combustion wave. 24