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In the event of a fire aboard the Orion Spacecraft, the Portable Fire Extinguisher (PFE) can introduce up to three pounds of water into the cabin to extinguish a fire. A filter was needed to work in conjunction with the Orion Fire Safety System (OFSS) to filter water out of the cabin atmosphere after dispersal from the PFE. Airflow introduced to the smoke filter of the OFSS must be dry and free of large particulates for the sorbent material to effectively extract smoke generated by a fire. These moisture and particulate concerns prompted a re-design of the original filter, especially a filter that could be tested in Earth’s gravity and yielding results that would transfer to a microgravity environment. The newly designed filter uses a multi-phase flow separation method that allows the airflow to develop fully in a helical flow path. This flow path resides within a wicking material used to separate the liquid from the gas (air) while also trapping particulate matter. Helical flow paths implemented in the filter impart a centrifugal force upon the incoming gas/liquid mixture that develops an asymmetric liquid film on the inner contour of the helix. Upon active airflow, the larger water droplets are inertially forced into the inner contour flow path wall. The flow path walls are made from a wicking material, and all liquid film and liquid droplets that are inertially deposited onto the walls are adsorbed into the filter material. The resulting output flow from the filter is 100% gas. The Corkscrew Filter has a technology readiness level (TRL) of 5 (component and/or breadboard validation in relevant environment) and is now available for patent licensing. Please note that NASA does not manufacture products itself for commercial sale.

This NASA technology transforms a conventional infrared (IR) imaging system into a multi-wavelength imaging pyrometer using a tunable optical filter. The actively tunable optical filter is based on an exotic phase-change material (PCM) which exhibits a large reversible refractive index shift through an applied energetic stimulus. This change is non-volatile, and no additional energy is required to maintain its state once set. The filter is placed between the scene and the imaging sensor and switched between user selected center-wavelengths to create a series of single-wavelength, monochromatic, two-dimensional images. At the pixel level, the intensity values of these monochromatic images represent the wavelength-dependent, blackbody energy emitted by the object due to its temperature. Ratioing the measured spectral irradiance for each wavelength yields emissivity-independent temperature data at each pixel. The filter’s Center Wavelength (CWL) and Full Width Half Maximum (FWHM), which are related to the quality factor (Q) of the filter, are actively tunable on the order of nanoseconds-microseconds (GHz-MHz). This behavior is electronically controlled and can be operated time-sequentially (on a nanosecond time scale) in the control electronics, a capability not possible with conventional optical filtering technologies.