Project purpose: To create a filtration system that removes bulk particulate matter out of air stream prior to HEPA filtration with a solution that is lightweight, regenerable and efficient.
The intrusion of planetary dust inside space vehicles on future lunar missions may lead to performance compromises of the cabin air-filtration system. The evasive character of the fine lunar dust could enable the dust to make its way through the seals and barriers of the EVA hatches and become airborne in the cabin. This can result in performance and capacity overload of the filter system. Adequate pre-filtration can substantially reduce the load on the higher efficiency components of the filter system, thereby protecting and extending the life of these components. A particle separation concept, based on centrifugal separation, is being investigated for its application as a pre-filter. The concept has previously been proposed for application in the aircraft engine industry, as means of capturing corrosive dust and salt deposits that may harm the engine. The technique has the advantages of being passive, integrable to HVAC and space vehicle architecture, and has the potential for high degree of particle separation with proper fluid dynamic design. Computational Fluid Dynamics (CFD) and particle tracing modeling were used to arrive at an initial design for rapid prototyping and testing. If feasible, the concept can be integrated to the Scroll Filter System which is being developed by NASA to address the filtration demands on long duration spaceflight and surface missions. Computational modelling shows positive separation of larger airborne particles for to potential centrifugal filter designs, for which prototypes were created and further testing is required.