Raimondo Fortezza

Agro-biology for bioregenerative Life Support Systems in long-term Space missions: General constraints and the Italian efforts

Abstract Future Space stations and Space habitats/outposts should be envisioned as self-sufficient ecological closed or semi-closed systems. The Italian Space Agency (ASI) projects have involved many research groups from complementary areas with a final goal of designing a facility for plant cultivation in Space. It has been critical to (i) identify, for this particular environment, highly productive species able to optimize O2 production/CO2 consumption, and (ii) develop high-tech controlled environments. Research activities have included seedling production in simulated microgravity and in Space with the two-fold objective of (i) integrating the crew diet with fresh food, and (ii) studying specific biological phenomena. Another research topic concerned pollen biology as a critical component for seed-to-seed cycles but also for gametophytic selection. In this context, a review of the main scientific topics on plant Space biology and of the Italian efforts on agro-biology for bioregenerative Life Support Systems will be presented and discussed in this paper.

Heat pipes with self-rewetting fluids under low-gravity conditions

The work presents experimental tests about the performance of heat pipes filled with a “self-rewetting“ fluid (alcohol aqueous solutions). Comparison with conventional commercial water heat pipes is also considered. The used fluid exhibits an anomalous increase in the surface tension with increasing temperature. Along these lines, the fluid has been investigated as a possible means to improve heat transfer inside the heat pipes with a focus, in particular, on space applications (next generation satellites). The experiments have been carried out both in normal and in low-gravity conditions (attained onboard a ‘zero-g’ plane, during a parabilic flight campaign). The results have confirmed improved capability of the considered heat pipes with respect to traditional heat pipes filled with water.

Flight results on Marangoni flow instability in liquid bridges

Abstract This paper reports on the results of the experiment PULSAR (Pulsating and Rotating Instabilities in Oscillatory Marangoni Flows), performed on the MAXUS 3 Sounding Rocket launched last November from the Swedish base in Kiruna. Aim of the experiment was the study of the oscillatory Marangoni convection in a cylindrical liquid bridge of silicone oil with kinematic viscosity of 5cSt. The experiment was motivated by preliminary on-ground numerical simulations and microscale experimental studies, that have pointed out that the oscillatory Marangoni instability appears at the beginning in the form of a pulsating regime, caused by a hydro-thermal standing wave, and then it turns to a rotating regime, caused by a traveling wave. The height of the bridge was equal to the disk diameter (20mm), and the imposed temperature difference was 15K during the first 460 s and 20K in the second part of the experiment, until the end of the microgravity period. The analysis of the temperature profiles, measured by thermocouples located near the disks at the same radial and axial coordinate but at different azimuthal coordinates (shifted at 90°), and the surface temperature distribution, measured by an infrared thermocamera, show that a pulsating and a mixed pulsating-rotating regimes have been established during the experiment. Unfortunately during the flight the accelerations level caused by two centrifuges with some biological samples in an adjacent module were above the expected values, so that disturbing g-jitter were encountered at different times during the microgravity mission. The effects are clearly visible and the numerical simulations had to make different assumptions to correlate the experimental results

System and technologies utilized in the first telescience experiment during Texus 23 mission

Abstract Texus 23 mission included a fluid dynamic experiment on the oscillatory Marangoni flow. The experiment was successfully performed on board the Texus sounding rocket (launched at Kiruna - Sweden) using TEM-06/4 module. It was fully controlled by the PI (Prof. Monti) directly from the Italian Control Center at Fucino. This new operative mode has been developed on Texus to test and to assess the principal technical aspects, and to demonstrate the validity and the usefulness mainly in the perspective of Columbus utilization. The paper illustrates the different technological aspects and the systems/equipment integrated and realized for the experiment control. In the first part the different possible H W configurations for the monitoring and control, identified by the research team, are discussed and compared with the selected architecture and subsystems, whose main features and limits are reported. The relevant aspects of the H W configuration include: the Control Work Stations architecture, the I O channels used for the selection, transmission and reception of data and commands, the sub-systems manufactured to improve the system reliability and safety level in the experiment operations. The second part deals with the communication network used for transmission between Sweden and Italy of experimental data, facility status, voice, video images, and commands. The role played by the S W for a complete, comprehensible presentation of the many parameters relevant for the experiment control is discussed in the third part. The S W , developed by the team, carried out different functions, as data selection and acquisition, graphic visualization, management of data/commands communication, data elaboration, facility/links monitoring, and decisional support to PI. In particular the experience acquired during this experiment has demonstrated the importance and usefulness of the decisional support, conceived to help the PI at the branch points. Finally the paper summarizes the experiment execution, the behaviour of the different sub-systems and the improvements obtained with respect to previous Texus experiences.

Results of numerical modelling and experimental activities in preparation of the maxus-5 experiment

Abstract The present paper reports on the research activities in both experimental and numerical field carried out at MARS center for the realization of an experiment on the thermo-solutal-capillary migration of a dissolving drop, composed by a liquid binary mixture having a miscibility gap. The experiment will be carried out onboard of the sounding rocket MAXUS 5, by using the INEXMAM facility. The main goals of the analysis are ensuring that the diagnostic equipment performances cope with the stringent resolution requirements dictated by the physics and assessing of the experiment time profile.

User support to AFPM fluid science experiments during the D2 mission

Abstract The Second German Spacelab mission (D2) includes five Fluid Science experiments performed on the Advanced Fluid Physics Module (AFPM). MARS research group has been directly involved in the preparation and execution of the Onset experiment, whose principal investigator (PI) was Prof. R. Monti. On this occasion a support infrastructure has been developed to assist the PI in the experiment execution; these support tools have been also used by other PIs of the AFPM experiments. The objective of this paper is to give a detailed description of the MARS control room, of the equipment and s/w codes specifically developed to support the D2 mission, and of the operations performed during the mission.

Telemaxus: A telescience oriented sounding rocket experiment

Abstract Following the success of the Texus 23 Campaign (November 1989), during which the Teletexus experiment was conducted a more ambitious Telescience experiment was accomodated on the 1991 MAXUS 1 Payload. The fluidynamic experiment on the oscillatory Marangoni flow was performed on board the rocket (launched at Kiruna, Sweden) using a modified TEM-06/4 module. The experiment was fully controlled by the PI (Professor Monti) directly from the Telescience Control Room located at MARS Center (Naples, Italy). The experiment was also aimed to demonstrate the capabilities of Telescience Service that ESA offers to the European Microgravity User Community. Respect to other experiments already tested and assessed during previous Texus missions (14b, 23), the Telescience operation mode included new state-of-art technologies and subsystems to demonstrate capabilities, flexibility and usefulness of this operation concept mainly in the perspective of Columbus utilization. Unfortunately due to a failure of the rocket system, the microgravity condition was not reached during the flight and the fluidynamic results were missed. However, in spite of the tumbling attitude of the rocket, the telescience link was successfully tested and the video/data/audio communication was correctly established between MARS and Esrange. This paper illustrates the technological aspects and gives an overview of the systems/equipments integrated and realized for the experiment control. In the first part the H/W configurations for the experiment monitoring and control, identified by the research team are illustrated. The relevant items of the H/W configuration include: the Telescience Work Stations architecture, the link channels used for the selection, transmission and reception of video/data/commands and the subsystems manufactured to improve the system versatility. The second part deals with the communication link used for transmission between Sweden and Italy of experimental data, facility status, voice, compressed video images, and commands, The role played by the S/W for a complete, comprehensible presentation of the many parameters relevant for the experiment control is discussed in the third part. The S/W, developed by the team, carried out different functions, as data selection and acquisition, graphic visualization, management of data/commands communication, data elaboration, facility/links monitoring, and decision support to PI. In particular the experience acquired during this experiment has demonstrated the importance and usefulness of the decision support, conceived to help the PI at the branch points. Finally the paper summarizes the experiment procedure, the behaviour of the different subsystems and the improvements obtained with respect to previous Texus experiences. The activities were carried out under ESA Contract 9392/91/NL/SF(SC).