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Louise Strutzenberg

Publications and source records attributed to Louise Strutzenberg.

Topical. Permanent Low-Earth Orbit Testbed for Welding and Joining: A Path Forward for the Commercialization of Space

NASA, defense, academia, and commercial space companies seek to develop orbital manufacturing to enhance mission capabilities. In-space welding and joining are needed for space-based manufacturing. We propose a permanent low-earth orbital welding and joining testbed for scientific study of relevant physical phenomena and development of welding and joining processes to technical maturity. Such data will enable integrated computational materials engineering(ICME)to elucidate the underlying physical and metallurgical processes needed to achieve critical space welding and joining operations.

In-space manufacturing↗

Experimental Observations of Mechanisms of Pattern Formation During Freeze Casting

Empirically, many different materials compositions have been freeze cast over the years. Few have been analyzed to better understand the mechanisms by which the ice crystal growth drives structure formation, particularly the substructures on the cell walls. Collating substructural features, for example, ridges, bridges, and “jellyfish-like” substructures, found on the cell walls of freeze-cast ceramics (platelets versus particles), fibrillated biopolymers (collagen, nanocellulose), and "smooth" biopolymers (chitosan, trehalose), we capture the ice crystal growth process and analyze it both in situ in 2D and "post-mortem" in 3D to gain insights into anisotropic ice crystal growth and other self-assembly mechanisms. Combining these experimental observations with 3D Phase-field simulations of structure formation in ice-templated materials, detailed in a companion presentation, it becomes possible to gain fundamental science insights and to obtain the desired structure-property-processing correlations not only at the more traditional macroscopic, but also at the meso- and microscopic scales.

Kaiyang Yin↗

TO252: Parabolic Flight Demonstration of Fluid Dispensing Tube Performance Limits for Drop Delivery

Ring Shear Drop (RSD) ISS flight hardware failed to pin sample fluid drops between two rings, likely due to dynamic instability inherent to the dispensing tube (D-Tube) design. The first parabolic flight tested 5 D-tube tip designs with two bounding surface tension fluids, enabling an engineering design decision. D-tube Tip Cage Design was selected based on the November 2020 parabolic flight test data. Flight Operations Program (FOP) approved a reflight proposal to include 2 parabolic flight days during the April/May 2021 campaign with following objectives: • Validate ISS hardware flight design with actual flight fluids (test as you fly), demonstrating the ability to deliver 1” fluid drops in near-microgravity conditions. • Demonstrate pinning of 1” flight fluid drops: a secondary pinning ring is planned to be installed in the parabolic flight hardware to meet this objective. Fluid flow rates will also be varied as needed and as possible. • Provide data to validate computational models used to guide ISS operational deployment decisions and demonstrate the viability of the redesigned hardware to accommodate a range of future flight investigations. This presentation introduces highlights and lessons learned during this recent flight campaign for discussion in the Flight Opportunities Program Panel, “Leveraging Suborbital Flight Tests to Advance Science and Technology."

Sridhar Gorti↗

Geopolymer Concrete – A greener alternative on Earth and a feasible material for the Moon

This research is focused on designing in-situ-based concrete material for extraterrestrial construction. Five regolith lunar simulants varying in their compositions were tested and their mechanical performance tested. The results have shown that the lunar regolith simulants are feasible for such concrete technology but exhibit variability due to their mineralogy, amorphous (glass) content, and particle size and shape distributions.

Peter J Collins↗

Influence of the Space Environment on Geopolymer Lunar Concrete

NASA is set to embark on the next era of human space exploration on the Artemis program. An eventual goal of the program is to maintain a human presence on the lunar surface. With such a goal comes the challenge of providing durable infrastructure that is suitable for the Moon and utilizes in-situ resources. Bringing materials form Earth poses a financial burden and increased safety concern. The composition of the lunar soil makes it advantageous to create a geopolymer concrete material. The lunar regolith can be used in the as found condition on the lunar surface and most of the mixing solution can be extracted form the regolith. It is envisioned than any concrete infrastructure would make use of additive manufacturing techniques with a temporary controlled environment enclosure to mitigate the harsh lunar conditions. Data is needed to benchmark how the material behaves once exposed to such an extreme environment so structural failures are mitigated.

Peter J. Collins↗