Simulation of Charge Formation Dynamics in EHD Systems with Different Electrodes

Purpose. Carry out numerical simulation of electrohydrodynamic heat exchange processes for dielectric liquids in various electrode systems. Obtain a mathematical model for numerical calculations of electrohydrodynamic flows and heat transfer properties of electrohydrodynamic systems using the finite element method; develop a program in the C++ programming language that implements the resulting model; carry out numerical simulation of electrohydrodynamic flows for dielectric liquids in various electrode systems.

Methods. Numerical modeling of EHD processes was carried out using the finite element method using the FreeFem++ library for the C++ programming language, which implements the main algorithms of this numerical method for solving partial differential equations. The three-ion model was chosen as a theoretical model describing EHD processes. As a model of computational fluid dynamics, the k-ε turbulence model was used.

Results. A program has been obtained that implements the three-ion model of EHD processes in numerical calculations of electrohydrodynamic flows by the finite element method for the two-dimensional case, numerical simulation of electrohydrodynamic flows has been carried out, as well as the calculation of the density of the injection and impurity charge, for dielectric liquids in systems of electrodes of the type " two parallel wires", "needle over plane" and "plate capacitor".

Conclusion. The obtained software implementation of the application of the three-ion model for numerical calculations of EHD processes makes it possible to simulate EHD flows in various electrode systems, which can be useful for a theoretical analysis of the prospects for using one or another electrode geometry for practical purposes.

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