scholarly journals Research and Verification of Key Techniques in the Simulation of Space Extremely Rapid Decompression in Millisecond

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Junwei Wang ◽  
Lei Zhang ◽  
Guohua Li ◽  
Ran Liu ◽  
Juan Ning ◽  
...  

The research of rapid decompression with its effect assessment and protection technology is the problem that must be faced by the future exploration projects such as near space exploration, deep space exploration, and long-term lunar or Mars base. A new reusable quick opening mechanism which can be opened in millisecond is designed to meet the testing requirement of ground simulator for extremely rapid decompression, and the testing results show that the quick opening mechanism can be opened within 0.1 s. The mathematical formulation is also developed, and the comparisons with the results from the literature demonstrate its validity. The CFD simulation and the verification system are established for the airflow in the rapid decompression process under different opening degrees. The simulation results show that the effect of the opening on the decompression process is very obvious and the decompression time corresponding to 50%, 75%, and 100% opening is 479.1 ms, 320.7 ms, and 290.1 ms, respectively. The testing results also show a consistent trend which is 583 ms, 450 ms, and 384 ms, respectively, to reach the equilibrium state.

Author(s):  
James F. Soeder ◽  
Anne Mcnelis ◽  
Raymond Beach ◽  
Nancy McNelis ◽  
Timothy Dever ◽  
...  

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
J. N. Chung ◽  
Jun Dong ◽  
Hao Wang ◽  
S. R. Darr ◽  
J. W. Hartwig

AbstractThe extension of human space exploration from a low earth orbit to a high earth orbit, then to Moon, Mars, and possibly asteroids is NASA’s biggest challenge for the new millennium. Integral to this mission is the effective, sufficient, and reliable supply of cryogenic propellant fluids. Therefore, highly energy-efficient thermal-fluid management breakthrough concepts to conserve and minimize the cryogen consumption have become the focus of research and development, especially for the deep space mission to mars. Here we introduce such a concept and demonstrate its feasibility in parabolic flights under a simulated space microgravity condition. We show that by coating the inner surface of a cryogenic propellant transfer pipe with low-thermal conductivity microfilms, the quenching efficiency can be increased up to 176% over that of the traditional bare-surface pipe for the thermal management process of chilling down the transfer pipe. To put this into proper perspective, the much higher efficiency translates into a 65% savings in propellant consumption.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Adriana Salatino ◽  
Claudio Iacono ◽  
Roberto Gammeri ◽  
Stefano T. Chiadò ◽  
Julien Lambert ◽  
...  

AbstractOrienting attention in the space around us is a fundamental prerequisite for willed actions. On Earth, at 1 g, orienting attention requires the integration of vestibular signals and vision, although the specific vestibular contribution to voluntary and automatic components of visuospatial attention remains largely unknown. Here, we show that unweighting of the otolith organ in zero gravity during parabolic flight, selectively enhances stimulus-driven capture of automatic visuospatial attention, while weakening voluntary maintenance of covert attention. These findings, besides advancing our comprehension of the basic influence of the vestibular function on voluntary and automatic components of visuospatial attention, may have operational implications for the identification of effective countermeasures to be applied in forthcoming human deep space exploration and habitation, and on Earth, for patients’ rehabilitation.


Author(s):  
J. Wright ◽  
S. Burleigh ◽  
M. Maruya ◽  
S. Maxwell ◽  
R. Pischel

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