This thesis is focused on the development of a preliminary numerical model for a Helicon Plasma Thruster (HPT). Specifically, two algorithms are introduced to describe plasma generation within the source tube: a quasi one-dimensional model and a volume-averaged zero-dimensional Global Source Model (GSM). In addition, a model of the magnetic nozzle (MN) is developed and then coupled with the two source models. All of the proposed models are evaluated and compared with each other, enabling a thorough analysis of their features and performance. The combination of the GSM and the MN is validated against experimental data taken from three different cathodeless plasma thrusters to assess both the qualitative and quantitative accuracy of the developed models. Then, a sensitivity analysis is conducted on various design parameters (radius, length, total input power, mass flow rate, magnetic induction, and number of cusps), focusing on the key plasma characteristics and propulsive properties of a helicon plasma thruster, utilizing the presented algorithms. A qualitative and quantitative investigation and comparison of the propulsive performances of different propellants are conducted, proposing a more accurate chemical model for the plasma source. Finally, a detailed numerical model of a birdcage antenna, which is employed to emit electromagnetic waves for ionizing the gas within the plasma source, is presented. The work is done for the company Stellar Space Industries, which is developing a novel RF plasma thruster.
Questa tesi si concentra sullo sviluppo di un modello numerico preliminare per un Helicon Plasma Thruster (HPT). In particolare, vengono introdotti due algoritmi per descrivere la generazione del plasma all’interno del tubo sorgente: un modello quasi unidimensionale e un modello globale a zero dimensioni (GSM) basato sulla media volumetrica. Inoltre, viene sviluppato un modello dell’ugello magnetico (MN) e poi accoppiato con i due modelli della sorgente. Tutti i modelli proposti vengono valutati e confrontati tra loro, consentendo un’analisi approfondita delle loro caratteristiche e prestazioni. La combinazione tra il GSM e il MN viene validata confrontandola con dati sperimentali ottenuti da tre diversi propulsori al plasma senza catodo, per valutare l’accuratezza qualitativa e quantitativa dei modelli sviluppati. Successivamente, viene condotta un’analisi di sensitività su vari parametri di progetto (raggio, lunghezza, potenza totale di input, portata massica, induzione magnetica, e numero di cuspidi), concentrandosi sulle principali caratteristiche del plasma e sulle proprietà propulsive di un helicon plasma thruster, utilizzando gli algoritmi presentati. Viene inoltre eseguita un’analisi qualitativa e quantitativa delle prestazioni propulsive di diversi propellenti, proponendo un modello chimico più accurato per la sorgente di plasma. Infine, viene presentato un modello numerico dettagliato di un’antenna birdcage, utilizzata per emettere onde elettromagnetiche che ionizzano il gas all’interno della sorgente di plasma. Il lavoro è stato svolto per l’azienda Stellar Space Industries, che sta sviluppando un nuovo propulsore al plasma a radiofrequenza.
Numerical modeling of Helicon Plasma Thrusters: from source design to performance and sensitivity analysis
PETRINI, MATTIA
2023/2024
Abstract
This thesis is focused on the development of a preliminary numerical model for a Helicon Plasma Thruster (HPT). Specifically, two algorithms are introduced to describe plasma generation within the source tube: a quasi one-dimensional model and a volume-averaged zero-dimensional Global Source Model (GSM). In addition, a model of the magnetic nozzle (MN) is developed and then coupled with the two source models. All of the proposed models are evaluated and compared with each other, enabling a thorough analysis of their features and performance. The combination of the GSM and the MN is validated against experimental data taken from three different cathodeless plasma thrusters to assess both the qualitative and quantitative accuracy of the developed models. Then, a sensitivity analysis is conducted on various design parameters (radius, length, total input power, mass flow rate, magnetic induction, and number of cusps), focusing on the key plasma characteristics and propulsive properties of a helicon plasma thruster, utilizing the presented algorithms. A qualitative and quantitative investigation and comparison of the propulsive performances of different propellants are conducted, proposing a more accurate chemical model for the plasma source. Finally, a detailed numerical model of a birdcage antenna, which is employed to emit electromagnetic waves for ionizing the gas within the plasma source, is presented. The work is done for the company Stellar Space Industries, which is developing a novel RF plasma thruster.File | Dimensione | Formato | |
---|---|---|---|
2024_12_Petrini.pdf
accessibile in internet per tutti a partire dal 08/11/2027
Descrizione: testo tesi
Dimensione
4.14 MB
Formato
Adobe PDF
|
4.14 MB | Adobe PDF | Visualizza/Apri |
I documenti in POLITesi sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
https://hdl.handle.net/10589/229754