静电发射器对微米级金属单颗粒的供应特性研究

Supply characteristics of micrometer-sized metal single particle by electrostatic generator

关键词:  静电发射器，颗粒弥散  单颗粒  供应特性  金属燃料  静电场

Key words:  Electrostatic generator  Particle dispersion  Single particle  Supply characteristics  Metal fuel  Electrostatic field

摘要:

为了对静电发射器的单颗粒供应特性进行系统性的研究，搭建了一套运动粒子可视化观测系统，并针对不同极板间电场强度、载气流量、几何结构和粒子直径条件下的发射器单颗粒供应特性进行了详细的研究分析。结果表明：利用静电场弥散颗粒群后，通过极低流量载气进行输运的颗粒发生装置可以稳定且连续的出射微米级金属单颗粒。通过提高电场强度、载气流量和扩大出口孔径，能够有效缩短粒子的出射时间间隔。其中极板间电场强度在影响粒子出射时间间隔上占主导地位，并且两者间具有较好的线性关系。在本文测试范围内，通过改变电场强度可以实现出射粒子平均时间间隔在180~1 100 ms内线性可调，同时单颗粒率保持在80%以上。为了稳定和高效的为燃烧试验供应单颗粒，建议粒子发射器的出口孔径不宜小于0.5 mm，载气流量不宜超过16 ml/min。

Abstract:

In order to systematically study the single particle supply characteristics of an electrostatic generator， a moving particle visualization observation system was built， and the single particle supply characteristics of an electrostatic generator under different electric field intensities between the electrode plates， carrier gas mass flow rates， geometric structures， and particle diameters were studied and analyzed in detail. Results show that the particle generating device that uses the electrostatic field to disperse the particle group and then transports it through the carrier gas with a very low mass flow rate can stably and continuously emit micron-sized metal single particle. By increasing the electric field intensity， the mass flow rate of the carrier gas and enlarging the outlet aperture， the time interval of particle ejection can be effectively shortened. Among them， the electric field intensity between the electrode plates plays a dominant role in affecting the time interval of particle ejection， and there is a good linear relationship between the two. In the test range of this paper， by changing the electric field intensity， the average time interval of the emitted particles can be linearly adjusted in the range of 180~1 100 ms， and the proportion of single particles can be kept above 80%. In addition， in order to stably and efficiently supply single particles for single particle combustion experiments， the outlet aperture of the particle generator should not be less than 0.5 mm， and the mass flow rate of the carrier gas should not exceed 16 ml/min.