Effect of Non-Equilibrium Plasma Pretreatment on Combustion Characteristics of Propane/Air Mixtures

Abstract

The feasibility of using non-equilibrium plasma to pretreat in-cylinder mass at low in-cylinder pressures in internal combustion engines to improve the combustion process is explored. In a propane/air mixture with an initial pressure of 0.1 MPa, an initial temperature of 303 K, and an equivalence ratio of 1, and based on a high-frequency nanosecond pulse-driven along-surface dielectric barrier discharge plasma generation system, the morphology and energy characteristics of discharge of propane-air mixture and the effect on combustion at different ignition intervals and numbers of discharge pulse are studied in a constant-volume combustion bomb. The results of the discharge test show that the energy of a single pulse is about 5.2 mJ. The average power is 30 kW, and 80 pulses at 80 μs intervals produce approximately 40 discharge channels. When the mixture is treated with 80 pulses at 80 μs intervals, the combustion duration is reduced by 1.33 ms, which is a 16% reduction. As the number of discharge pulses increases, the burning duration first decreases linearly and then stabilizes, and the duration of combustion increases with the increasing ignition interval.

Keywords

• nanosecond pulse discharge
• nonequilibrium plasma
• combustion control
• surface dielectric barrier discharge (sdbd)