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React cold plasma enriched space ions, electrons, excited atoms, molecules, and free radicals are a very lively reactive species, these active particles more easily and the contact surface of the material, thus can be used for processing the material surface . Currently, the majority of low-temperature plasma is in the hundreds of bar low pressure gas discharge produced, but for large-scale industrial production, low pressure plasma high investment, the application is complex, difficult to continuous production problems. Therefore, the most suitable for industrial production is a discharge plasma generated under atmospheric pressure in air. Dielectric barrier discharge (Dielectric Barrier Discharge: DBD) under certain conditions, can be transformed into a uniform glow discharge of class, and therefore has been used for the plasma surface treatment. However, in an air atmosphere under atmospheric pressure, the above-described class glow state is difficult to obtain, its discharge mostly by the diameter is small, but a large current density of the filaments, uniform processing is difficult to a material surface, or even cause the medium or test product surface ablation or perforation, and therefore the air under atmospheric pressure to obtain uniform distribution and moderate-intensity discharge will be of great significance. This study found that the use of high-speed airflow will help to enhance the stability and the uniformity of the running of the air under atmospheric pressure DBD. This experiment uses a frequency of 300 Hz-10 kHz adjustable AC power supply, the peak voltage of 40 kV, using the parallel plate electrode structure (unilateral cover medium), and using a hair dryer to control the flow rate of gas of the discharge space, studied the high-speed air stream under atmospheric pressure. air DBD morphology and intensity. The article first introduces the experimental conditions, such as voltage, frequency, discharge gap running airstream was found: in the airstream, the higher the voltage, the discharge, the stronger, the streamer channel also tends to be fixed; frequency increases, the discharge intensity is also enhanced, and an increase in the positive half cycle amplitude is significantly faster than the negative half cycle, more stable streamer channel; discharge gap is reduced, the breakdown voltage is significantly decreased, and discharge showing a seemingly homogeneous atm class hui Optical discharge. Then, the paper discusses the impact of air dielectric barrier discharge, on a set of data comparison: the addition of high-speed airflow, discharge Pattern from filamentous into ribbon and the ribbon of curvature value along with the airflow velocity increase and increase the discharge intensity decreases with the increase of the air velocity. Discharge morphology and intensity variations also influenced by the factors of the discharge frequency of discharge voltage and discharge gap, this article focuses on the discharge frequency, the study found: the higher the frequency, the discharge intensity is weaker, so that when the discharge frequency close to 500 Hz, the the discharge strength decreases with increasing air velocity, the trend has become very obvious. In order to verify the above conclusions, we measure the discharge frequency of 2 kHz, 1 kHz, 500 Hz plasma atomic emission spectrometry, the results showed that: the luminous intensity decreases with the addition of the airflow, and the trend is obvious; However, with the frequency decreases, the smaller the impact of the stream on the luminous intensity. The above trends and current intensity changes consistent. The paper also found that: when the fixed air velocity ribbon Pattern curvature does not change with the change in voltage, frequency, and the gap.
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