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Based on gliding arc discharge, a novel aero-engine combustor head is designed, which can realize three-dimensional rotating gliding arc discharge in turbulent flow field at atmospheric pressure. The spatiotemporally resolved characteristics and discharge modes of gliding arc discharge are studied, including gliding discharge (G-D) mode, breakdown discharge (B-D) mode, multi-cycle B-D (MB-D) mode, short-cutting discharge (SC-D) mode. And the conversion between different discharge modes are discussed by using optical and electrical parameters synchronous observation. In the G-D mode, the discharge voltage and current show sinusoidal variation, and the current amplitude is about several 100 mA. In B-D mode and MB-D mode, the current waveform appears as nanosecond spike, and the peak value can reach several amperes. The interaction between turbulent flow and electric field can lead to SC-D mode, which reduces the arc length suddenly and changes the discharge path of the arc. Air flow and input power will affect the discharge mode of the gliding arc. In the G-D mode, the arc will change to B-D mode as the length increases. When the power supply energy is enough to maintain the arc gliding, the arc in B-D mode will also change to G-D mode. In different discharge modes, the discharge power of the arc will also be affected by the air flow and power supply energy.

This paper investigates the ignition performances of plasma-assisted ignition in propane/air mixture. The results show that a shorter ignition delay time is obtained for the plasma ignition than the spark ignition and the average ignition delay time of plasma-assisted ignition can be reduced at least by 50%. The influence of air flow rate of combustor, the arc current and argon flow rate of plasma igniter on ignition delay time are also investigated. The ignition delay time of plasma-assisted ignition increases with increasing air flow rate in the combustor. By increasing the arc current, the plasma ignition will gain more ignition energy to ignite the mixture more easily. The influence of plasma ignition argon flow rates on the ignition delay time is quite minor.

The characteristics of the thermal evolution of aromatic maturity parameters, such as methyl phenanthrene, alkylated dibenzothiophene, dehydroxy-tocopherol and triaromatic-sterane series compounds are discussed on the basis of molecular organic geochemistry and GC-MS analysis of the source rocks in the Dongling area of the Songliao Basin. The distribution characteristics of aromatic hydrocarbon chromatography, the methyl phenanthrene index (MPI), the ratio of β/γ dehydroxy-tocopherol, 4-/1-MDBT, 4,6-/1,4-DMDBT, TASC27 (20R)/C28 (20R), the content of the triaromatic-sterane series and vitrinite reflectance measurements all suggest that the Lower Cretaceous Quantou Formation source rock is in the middle stage of maturity, whereas the Lower Cretaceous Yingcheng Formation and the Upper Jurassic Huoshiling Formation source rocks have reached a high maturity stage.

Based on nonequilibrium plasma dynamics of air discharge, the dynamic model of two-dimensional plasma is established by combining the plasma dynamic model, chemical reaction equations and Navier-Stokes equations. The discharge process of disk-shape plasma igniter is simulated. The process of discharge stream formation is obtained, which results from by electrons’ movement and aggregation. At