1. Numerical Simulations of Plasma-Spacecraft Interactions Near Irregularly Shaped Small Asteroids
Small airless bodies in the solar system (small asteroids and comets) represent the next frontier in deep space exploration. Proximity exploration of small asteroids present several extremely challenging issues for spacecraft. In particular, local plasma interaction with spacecraft in proximity of asteroids are highly unknown because irregularly shaped asteroids can produce a highly complex plasma flow field. This paper presents a numerical investigation of plasma interaction and charging for spacecraft near irregularly shaped asteroids. Large-scale particle-in-cell simulations are carried out with a mesh resolution that resolves the local plasma sheath around spacecraft and a simulation domain that contains the global plasma flow field around asteroid. Spacecraft charging is calculated directly from charge deposition on spacecraft. Spacecraft charging results will be presented for several different asteroid shapes and ambient plasma environments.
Details can be found here(Abstract submitted to 2019) PDF
Poster can be found here(Poster were presented during ASEC2019) PDF
2. Immersed-Finite-Element Particle-in-Cell Simulation of Dust-Plasma-Asteroid Interactions
While the dynamics of dust transport around an airless body has been a focused area of research in recent years, various challenging aspects still remain to be addressed for small asteroids where the dust dynamics is determined by the competing effects from gravitational force, electromagnetic force, and solar radiation pressure. This work presents a numerical investigation of dust transport and distribution around asteroids. The numerical models involved include a kinetic 3D particle-in-cell (PIC) using an immersed-finite-element based field solver.
Details can be found here(Abstract submitted to ISSS-13) PDF
Poster can be found here(Poster were presented during ISSS-13) PDF
3. Open architecture mars mission simulation
Since the last decade, Mars exploration has attracted peopls’ interest and has become a very important project for space exploration. In the previous study of the possible ways of Mars surface exploration, Mars Rover has been a very popular way. However, due to the range limitation, Mars rover is not sufficient to do global sample return. In this way, finding another way of Mars surface exploration has become a problem and in order to solve this problem we proposed a mission concept using the Mars Balloon.
In this work we considered two balloon models. The first model is a zero-pressure quasi-spherical balloon. We use the black PE material as the skin material and hydrogen as the fill-in gas. For the second model we use a super-pressure pumpkin-like balloon and assume the interior gas will not exchange with the outside gas. The skin material and inside gas are the same with the first model.
Details can be found in this poster(Presented on COSPAR 2018) PDF
4. The parallelization of DADI solver in PIC codes and its application to the simulation of Hall Thruster
Electric Propulsion is a new type propulsion method which is concerned by many of the researchers in the area of aerospace engineering. The working principle of the electric propulsion is to utilize the electromagnetic field to accelerate the plasma and then getthe thrust. In order to improve the design of the electric propulsion devices, understanding the physical principle of plasma becomes an unavoidable process.
Numerical simulation becomes a suitable research method due to the specialties of the plasma in the chamber of the electric propulsion devices. Among the types of simulation methods, PIC has been selected as an important method. This thesis developed a PIC code for the research of the electric propulsion plasma and used the code to calculate the physical condition in the chamber under different magnetic field. Meanwhile, this thesis provide a Parallelization method for this code and had make sure the parallel algorithm in this thesis is clear and right.
Details can be found here PDF