Mixed-Phase Ice Crystal and Droplet Characterization and Thermometry

This effort proposes to design, build, and demonstrate a new instrument for icing research and flight safety capable of discriminating liquid water from ice while simultaneously measuring the diameter, velocity, and temperature of droplets or the velocity and size for ice crystals. From these individual particle characteristics the total liquid water content (LWC) and the total water content (TWC) of the flow may be found. This non-intrusive, laser-based, point measurement diagnostic will operate in an off-axis, back scatter configuration at a range of working distances appropriate to characterize laboratory-scale experiments, icing tunnel flows, free jet test facilities, or flight conditions at altitude. The proposed instrument will apply phase-Doppler interferometry, polarization ratio phase discrimination, droplet rainbow thermometry, and cross-polarization imaging to each particle measured (see Part 4 for details on these techniques). This will provide joint measures of liquid/solid phase, velocity, diameter or particle size, and droplet temperature. Furthermore, there is redundancy built into the measurements. For instance, the droplet diameter can be measured both by phase-Doppler interferometry and by rainbow thermometry and all four measurement techniques can discriminate solid ice from liquid droplets. While no single instrument can measure all possible cloud droplets, the proposed instrument can be configured to measure droplets from as small as 3 μm to larger than 3 mm in diameter.

NASA's research into flight safety and aircraft propulsion would benefit from the successful commercialization of this instrument. Other governmental, academic, and industrial research groups in the areas of aircraft and flight safety, air-breathing and rocket propulsion, transportation, spray, drying, and other industrial processes would all stand to benefit from a diagnostic capable of exceptional phase discrimination and/or remote droplet temperature measurement. There are several possible paths to commercialization of this work either as improvements on our current commercial products or as entirely new products. The present SBIR Phase 1 will lead to a fully-developed instrument capable of simultaneously and redundantly measuring multiple physical properties of droplets and ice crystals. However, we do not believe that an instrument as described herein would be economically viable on its own. There are only a handful of ground-based icing research facilities that would be willing to invest the capital required to purchase such an instrument – several of which are already in possession of a PDI for droplet characterization. However, the proposed instrument is intentionally overcomplicated for the proof-of-concept phase.

Within the meteorology and icing research markets there is potential to create two separate product lines. Some researchers will prefer an in situ device that can be placed in a large wind tunnel flow or mounted to an aircraft exterior. Others may prefer an ex situ instrument that can be placed outside of the flow – the solicitation specifically mentions the profiling across the span of an engine duct. The proposed diagnostic methods are all suitable for both styles of measurement. Furthermore, since the proposed layout involves the use of backscatter collection, such an instrument could be deployed from within an aircraft's fuselage and pointed out a window with no impact on the flow or external mounting requirements. Such an instrument configuration could move beyond a research tool and be used as a real-time flight safety instrument to characterize the icing threat to the airframe. Moreover, there are a wide range of food processing applications using spray drying. The capabilities of measuring mixed phase particles and droplet temperature will be attractive to the R&D and process control in these environments. Efficient energy utilization and product quality are key concerns in these applications.

This is a mature technology (TRL 7) — the realistic path in is usually NASA's Technology Transfer Program: licensing an existing NASA patent, or a Space Act Agreement to use NASA facilities/expertise directly. NASA also runs a startup licensing program with no upfront fee for companies formed to commercialize a specific NASA technology.

None of these are guaranteed paths for this specific project — TechPort itself doesn't have an "apply" button. Reaching out to the contact(s) above with a specific question is usually the fastest way to find out what's actually open.