Numerical and Experimental Investigations of the CAMILA Hall Thruster Plume
Electric propulsion for space applications is a heavily expanding sector and is seen by many as the future of space propulsion. With budgets shrinking and frontiers expanding new classes of small spacecrafts are emerging and demanding high performance low power thruster systems. The CAMILA (Co-Axial Magnetically Insulated Longitudinal Anode) Hall effect thruster, developed at the Technion, proved to have one of the best existing performances for its power class thanks to the new concept employed in its design.
The aim of this research project is to fill the lack of knowledge about the properties of the plasma plume deriving from the particular ionization process of the thruster and to investigate the possibility for cluster implementation, in order to open the road for future space qualification of the system. The plume is in fact one of the major interfaces between the thruster and the spacecraft, and a possible source of concern.
In order to be able to understand and, more importantly, to predict plume properties a mathematical and numerical model has been implemented in the core of a computational code. Being all freely available plasma codes unfit for our necessities a new one has been developed from scratch and the first simulations have been made to prove its validity. In order to provide more detailed initial conditions and link the physical processes occurring in the plume with the ones occurring inside the channel the existing channel model has been adapted to include plume near-field.
The objectives of this work are, first to refine the plume model and capture the widest possible range of physical phenomena, while improving its numerical performance avoiding an excessive increase in computational time. A further fundamental step in increasing the accuracy of plume prediction is to increase the accuracy and reliability of input data. To this end channel and near field simulations will be completed and an experimental campaign will be carried out in Asher Space Research Institute facilities in order to collect the necessary information. The last step will be the validation of the code, which will be done with extensive experimental trials to take place both in ASRI and in other institutions with which cooperation is being established. These trials will also test clusters of two thrusters, and in particular the possibility of having impinging and diverging plumes in order to control the trust vector.
The results of the present research will give precious new insights on the CAMILA Hall thruster physical behavior and furthermore will be of critical relevance for its future implementation on new space missions.