A hybrid approach for corona discharge in needle electrode configuration: in a large-scale space

Abstract

Needle electrodes are widely used as the discharge electrode in charged particle-generating apparatus to study discharge characteristics due to their high efficiency. However, for the charged particle distribution of needle electrode corona discharge in a large-scale space (tens or even hundreds of centimeters), there is still a lack of an effective numerical simulation method. To solve this problem, a hybrid approach based on the combination of a hydrodynamic fluid model and an ion flow transport equation (ion drift model, based on the Kaptzov hypothesis) is put forward in this paper. The principle and implementation of the proposed method is introduced in detail. Further, the good consistency of the numerical simulation and a series of experiments under various applied voltages with two type sphere (radius 25 cm) apparatus, by comparing the charged particle density and discharge current, has demonstrated the accuracy and feasibility of the hybrid approach. This research provides an approach for the further study of corona discharge in a large-scale space, and implies the precise control potential in the application of low-temperature plasma, such as plasma material treatment, water treatments, gas disposal and so on.

Dividing and setting strategy of improving calculation efficiency for needle electrode corona discharge with a large‐scale space

“…The simulation results are higher than the mean measured value with a maximum error of 37% when the applied voltage is −13.1 kV. Note that the maximum current error of the needle‐plate electrode is a litter higher than that of the needle‐ball model (30% as described in [32]). The reason may be that the charged particles of the needle‐ball electrode are in a closed space, and all the charged particles can reach the ground electrode, whereas the needle‐plate electrode is in an open space, and the diffusion of the charged particles causes the error to become larger.…”

“…The governing equations in this article follow those in our previous article [32]. The governing equations of the ionization region are as follows: For the drift region, the ion flow transport equations are coupled with the Poisson equation [28].…”

“…The hydrodynamic fluid model has advantages in calculating complex electrode models and can provide the particle source needed by the ion flow transport model [18,19,27,33,34]. By this way, the spatial size of the computational domain can be increased to 25 cm [32]. Unfortunately, a large amount of calculation follows and further restricts the promotion and application of the proposed method.…”

Electrostatic Effects of Corona Discharge on the Spectrum and Density Evolution of Water Droplets in Air

“…When the corona discharge on the wire electrode array is triggered, the discharge current has a significant rise with a showing of the increase in space charge density, and the spatial scope of the strong electric field is also extended around the discharge device [36]. The electric field strength can be up to the order of 10 7 V/m and even larger at the vicinity of the wire electrode [37], which accelerates the collision growth of droplets rapidly. Hence, we can conclude that the class of electric field is a significant and dominant factor, which results in different electrostatic effects of corona discharge on the spectrum and density evolution of droplets.…”

Multi-scale two-domain numerical modeling of stationary positive DC corona discharge/drift-region coupling

“…The boundary condition associated with the drift region is clearly resulting from the interaction between the various fields (electric potential, ions, electrons) between the glowing and drift regions. This is why many modeling approaches have considered a coupled multi-domain or 'hybrid' approaches in order to model the physics of DC corona [34][35][36][37]. A major issue in this area is to foresee a relevant modeling using physical parameters only, (kinetically based parameters available from open data-bases) but avoiding the need of dedicated phenomenological parameters.…”