Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Modeling an electrospray propulsion system using an open-source Smoothed Particle Hydrodynamics method
Submission Author:
Diogo Leon Oliveira Soares , SP
Co-Authors:
Marcelo dos Santos Ferreira, Marco Antonio Gontijo Piantino, Ricardo Adriano, Diogo Leon Oliveira Soares, Alexandre Ramos Fonseca
Presenter: Marco Antonio Gontijo Piantino
doi://10.26678/ABCM.COBEM2023.COB2023-0394
Abstract
Over the past few years, Electric Propulsion (EP) has become increasingly popular for spacecraft. Many EP mechanisms exist, which accelerate plasma using electromagnetic forces, providing momentum for the spacecraft through high-speed plasma ejection. Among the technologies available, Electrospray Thrusters are being investigated by many researchers because of their small size, which is suitable for small spacecraft. To gain a comprehensive understanding of the physics behind thruster operation, a range of models have been proposed in the literature, including simple analytical models with limited accuracy and more complex weak-coupled Electromagnetic Fluid Dynamic numerical approaches. However, accurate and time efficient solutions are still unavailable. To solve this problem, this paper proposes an open-source Python tool based on the Smoothed Particle Hydrodynamics (SPH) method. SPH is a Lagrangian mesh-free approach that can naturally incorporate fluid dynamics physical effects, and it has been successfully applied to many fluid dynamics problems, such as free surface flow and electrophoretic deposition. The proposed tool aims to balance efficiency, simplicity, and code reuse. The Navier-Stokes governing equations are presented as state-space representation suitable for solving using the open-source Scientific Computing Python Library (SciPY), which offers a wide range of Initial Value Problem (IVP) solvers for performing the SPH integration scheme. This leads to a compact and fast code. The tool is validated using the Poiseuille Flow Problem, where the incompressible flow is induced by pressure gradient inside a duct, forming a parabolic velocity profile in steady-state condition. Analytical solutions are available to check the accuracy and performance of the different SciPy solvers. Computational aspects, including the neighbor particle search, surface detection, and boundary conditions modeling, are also investigated. For instance, the proposed search particle algorithm selects all the neighbor particles lying inside a rectangular-shaped area to check whether they lie inside the influence domain of the first particle, which decreases simulation time efficiently. The results obtained using different particle numbers showed good agreement with the analytical velocity profile, with errors ranging from 3% to 12%, depending on the particle number. Finally, the tool is validated and a simplified bidimensional planar Electrospray Thrusters model is simulated.
Keywords
Electrospray, Smoothed Particle Hydrodynamics, Electric Propulsion
