Numerical Investigation on Collector of Asteroid's Particles with Various Sizes

Collecting and returning samples from the asteroid's surface is one of the significant targets of the current asteroid detection. The key issue of the nitrogen purge sampling technology is the flow field design of the sample container. In order to ensure that the sample container has an efficient collection performance, the flow field design of the sample container must solve two key problems, one problem is the flow field how to form a trap effect on the sample particles, and another problem is the flow field how to effectively classify the sample particles. Therefore, the researchers proposed a scheme of the sample container, which uses the combined effect of centrifugal force and guide blade to collect and classify the sample particles. For verifying the performance and feasibility of this scheme in a microgravity environment, the researchers carried out the numerical simulation with Fluent software. Under the boundary conditions of the container, the simulation program calculated the velocity of nitrogen at the inlet, and the optimal value is 0.6 m·s^-1, the efficiency of the container at this velocity reaches 99.7%, the flow field of the sample container also has a good particle classification function, and its capture rate of particles that less than 2mm exceeds 90%. Its pressure loss is also within a reasonable range, the research results of this paper can provide a reference for the upcoming asteroid's sampling task in China.