USRA Collaborations make key contributions in the areas of Combustion, Fluid Physics, and Complex Fluids. These three areas of research are integral to the future of the exploration and commercialization of space.
USRA Continues to Make Key Contributions to Microgravity Research at NASA Glenn Research Center
USRA along with its subcontractor Case Western Reserve University (CWRU), continues to make key contributions to microgravity research at NASA GRC, on the Advanced Research and Development Support (ARTS) contract.
The USRA/CWRU Microgravity Research Team on ARTS had another outstanding year in FY2017, achieving mission success on numerous flight experiments on the International Space Station (ISS) while also supporting ground-based R&D that is the precursor of future ISS flight experiments. The following are a few highlights of the many scientific and technical accomplishments made by the team.
Cool Flames in Space
USRA and its team completed the Multi-User Droplet Apparatus culminating in development of the Combustion Integrated Rack onboard the ISS for the Cool Flames Experiment.
In September 2017, the Multi-User Droplet Combustion Apparatus (MDCA) culminated 8 1/2 years of operations in the Combustion Integrated Rack (CIR) onboard the ISS with the completion of the final in-space operations of the Flame Extinguishment Experiment (FLEX) series of investigations.
FLEX was a program of five separate experiment campaigns in droplet combustion that accomplished nearly 1,500 successful test points for investigators from ve countries and three space agencies. USRA and Case Western Reserve University have been integral members of the FLEX investigations, with our employees serving in a range of critical science roles for the family of experiments.
FLEX led to a 2012 ISS Research Discovery of the Year with the detection of a new “cool flame” mode of non-premixed combustion observed during the second stage burning of an alkane droplet. This discovery paved the way for the Cool Flames Investigation experiment and has significantly improved models of low-temperature chemical kinetics. The data from FLEX experiments will lead to better fuel efficiency and improved fire safety for applications on Earth and in space.
Fluid Physics and Complex Fluids
The Advanced Colloids Experiment with Temperature Control (ACE-TI) using the Fluids and Combustion Facility (FCF) onboard the International Space Station was successfully completed.
During ISS Increments 49-51, the ACE-T1 experiment investigated the particle behavior of 3 x 5-micron anisotropic colloidal Janus particles, as well as their self-assembly, in microgravity.
Microgravity provides a promising environment for acquiring a novel scientific understanding of these behaviors, something that is not observable on Earth where they are inhibited by gravitational sedimentation.
On Earth, it is hard to observe a structural difference of the assembled clusters expected from controlling the ratios of the hydrophobic and hydrophilic parts of the Janus particles. Only small-size dimers (N=2) are formed by each of the three types of the Janus particles, and no significant grown structures exist.
In contrast, microgravity allows the formation of various 3D clusters, and their structural differences are observed depending on the ratio of the hydrophobic and hydrophilic parts. The 3:7 convex-top Janus particles dominantly self-assemble into spherical morphology and the 5:5 convex-top Janus particles self-assemble into both 3D spherical and 3D linearly grown clusters. In the case of 7:3 Janus particles, formation of 3D linearly grown clusters are observed (see figure above).
USRA’s Dr. William Meyer – the ACE Project Scientist - worked with Professor Chang-Soo Lee, the Principal Investigator, and his student research team from Chungnam National University in South Korea.
The ACE-T1 investigation seeks to answer fundamental questions about behaviors of colloids, helping scientists to understand how to control, change, and even reverse interactions between tiny particles. This knowledge is crucial for developing self-assembling, self-moving, and self-replicating technologies for use on Earth. This novel fabrication approach may be applied to produce novel functional material in various applications such as self-assembly, photonics, diagnostics, and drug delivery.
Two highly successful experiments in the Spacecraft Fire Experiment (Saffire) family of investigations occurred in FY2017. The Saffire investigations were performed on the Cygnus Resupply Vehicle after it undocked from the ISS but prior to its destructive re-entry into the Earth’s atmosphere.
Saffire conducts the largest scale fire experiments ever performed in space, returning critical data on material flammability and flame spreading in a spacecraft environment. Both experiments achieved 100% mission success, with more than 100,000 images collected. Dr. Paul Ferkul (USRA) and John Easton (CWRU) are members of the Saf re science team.