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doi: 10.1007/s12217-009-9120-1pmid: N/A
The research facility DESDEMONA features a unique motion platform, combining a fully gimbaled cabin with the capability of producing sustained g-loads. Originally designed for ground-based simulation as well as training of spatial disorientation in aviation, the motion capabilities are also interesting for other areas. In this paper we will provide examples of space-related research questions that can be addressed on DESDEMONA. Some questions are concerned with centrifugation as a means to create artificial gravity. For instance, with its variable radius and gimbaled cabin, DESDEMONA allows for studying possible trade-offs between g-load and angular velocity. Other questions relate to the effects of g-level transitions on the astronauts’ well-being and performance. During the last two decades, research at TNO has shown that after prolonged exposure to centrifugation at 3 g astronauts experience the same vestibular adaptation symptoms as observed in real space flight. In DESDEMONA, the hyper-gravity stimulus can be applied and the consequences for control of simulated spacecraft can be examined in the same device. Furthermore, DESDEMONA also provides a ‘clinical’ tool for vestibular examination of astronauts, and for the provocation and desensitization of motion sickness in unusual G-environments.
Garrido, Leoncio; Sampayo, José
doi: 10.1007/s12217-009-9105-0pmid: N/A
In situ proton stray-field (STRAFI) nuclear magnetic resonance (NMR) imaging of diamagnetic samples in simulated microgravity is described. The magnetic field gradient at the edge of the superconductive coil in the magnet of a NMR spectrometer is exploited to levitate diamagnetic samples and, at the same time, obtain their corresponding one-dimensional NMR images. Proton T 2 (spin-spin relaxation time)/ diffusion-weighted profiles of samples under simulated microgravity conditions are acquired with a solid-echo radiofrequency pulse sequence. Since water is a diamagnetic main constituent substance of living systems, the methodology described could be useful to monitor non-destructively changes in the NMR properties of water protons induced by simulated microgravity and magnetic forces. Furthermore, this approach may be used to observe other NMR-sensitive nuclei of interest, e.g., fluor-19, phosphorous-31, carbon-13, etc.
Flikweert, A.; Nimalasuriya, T.; Kroesen, G.; Haverlag, M.; Stoffels, W.
doi: 10.1007/s12217-009-9106-zpmid: N/A
Diffusive and convective processes in the metal-halide lamp cause an unwanted axial colour segregation. Convection is induced by gravity. To understand the flow phenomena in the arc discharge lamp it has been investigated under normal laboratory conditions, micro-gravity (ISS and parabolic flights) and hyper-gravity (parabolic flights 2g, centrifuge 1g–10g). The measurement techniques are webcam imaging, and emission and laser absorption spectroscopy. This paper aims to give an overview of the effect of different artificial gravity conditions on the lamp and compares the results from the three measurement techniques.
Kozlov, Victor; Ivanova, Alevtina
doi: 10.1007/s12217-009-9165-1pmid: N/A
The results of theoretical and experimental investigation of the average dynamics of inhomogeneous systems in rotating cavity in the presence of oscillating force field are highlighted and analyzed. Average behavior of nonisothermal liquid as well as different multiphase systems (two liquids, liquid and gas, solid in liquid, granular matter in liquid) in quickly rotating horizontal cylinder subjected to vibrations of different direction is described. The specificity of dynamics of all the systems is determined by the Coriolis force which defines not only the average flows but the fluid oscillations also. The resonant excitation of inertial oscillations of liquid results in generation of intensive mean flows. The structure of vibrational streams is essentially determined by the type of inertial waves. So, excitation of an azimuthal wave generates azimuthal streams (outrunning or lagging, depending on frequency of the wave), three-dimensional standing waves (in the systems with deformable interface) generate regular spatial flows of high intensity. Under the resonant conditions the influence of vibrations appears to be very strong, the speed of mean streaming can achieve the values comparable with the speed of rotation of the container.
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