Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Watery load for Ariane 5 ECA

20.09.2004


When the Ariane 5 ECA qualification flight lifts off in October, one of the ‘passengers’ will be 33.5 litres of water. Onboard will be the experimental Sloshsat-FLEVO satellite, designed to help European scientists find out more about the movement of water in microgravity and its effects on satellites.

Sloshsat-FLEVO is aptly named: slosh for the movement of water, sat for satellite and FLEVO, the project’s acronym: Facility for Liquid Experimentation and Verification in Orbit. Flevo is also the name of the latest province in the Netherlands to be reclaimed from the sea, and one of the sites of the Dutch National Aerospace Laboratory (NLR), the main contractor for this project. The cube-shaped Sloshsat-FLEVO is a mini satellite with a mass of just 129 kg. It will be launched on top of the cylinder-shaped Maqsat-B2 structure and placed in the lower passenger position under the Ariane 5 fairing.

This joint project between ESA’s Technology Research and Development Programme and the Netherlands Agency for Aerospace, is funded mainly through ESA’s General Study and Technology Programme. Sloshsat is designed to investigate fluid dynamics in microgravity conditions by monitoring the behaviour of 33.5 litres of deionised water, placed in a tank onboard the small satellite.



The composite tank has 270 sensors to measure the water’s distribution. Other sensors will measure the temperature, pressure and fluid velocity at 17 locations, and six accelerometers and three fibre-optic gyroscopes will monitor the spacecraft’s motion. Thrusters, powered by a cold gas nitrogen system, will provide linear and rotational movement to increase and control fluid motion.

This is the first time that a satellite has been dedicated to studying fluid behaviour in weightlessness. Spacecraft transporting supplies to the International Space Station, carrying out repairs to disabled communication and observation satellites or heading for other planets, often carry large quantities of fluids onboard in the form of propellant or water. This is why it is important to fully understand the effect a liquid’s movement can have on the attitude control of these spacecraft.
Many fluid dynamic models exist, as well as computational fluid dynamics (CFD) software, but to date the effect of sloshing on spacecraft control has been difficult to predict for real situations as it has not been validated.

Jan Vreeburg of NLR, the Principal Investigator for Sloshsat says “once the satellite is in orbit, scientists will be able to verify and validate existing models”. This will allow them to design new CFD numerical algorithms and liquid management systems for spacecraft.
As well as testing the effect of liquid movement on the attitude control of a spacecraft, Sloshsat-FLEVO will also test the effect of spacecraft manoeuvres on liquids. “For example,” reports Vreeburg, “tests will show us how best to manoeuvre a spacecraft to move the liquid in a tank near to the exit hole; this has to be done carefully to avoid ‘ingesting’ bubbles. Once thrust is generated by the engine, its action generally keeps the propellant at the exit hole.”

Almost ready for launch

Sloshsat-FLEVO has been installed inside the Sylda 5 multiple payload deployment system at Europe’s Spaceport in French Guiana since the end of August. On top of the Sylda is another passenger bound for space, an XTAR-EUR telecommunications satellite.

ESA’s spring-loaded ESAJECT mechanism, developed and built by the Belgian company Verhaert for 50 – 150 kg satellites, will eject Sloshsat-FLEVO once the launcher reaches geostationary transfer orbit. The satellite will then transmit data on the behaviour of the water in its tank under different motions controlled from the ground, for a minimum of 14 days. The total experiment time will be about 24 hours and last until the gas supply of the reaction control system is exhausted. Between experiment runs the water is allowed to settle and the battery will be recharged using solar panels.

Staff at the ESA Diane ground station in Kourou, French Guiana will control the satellite with the support of ESA’s European Space Operations Centre in Darmstadt, Germany. During operations, the Principal Investigators will be able to follow Sloshsat in near real time via the internet, from a server located at ESTEC, ESA’s European Space Research and Technology Centre in the Netherlands. Telemetry data will enable a virtual reality image to be created of both Sloshsat and the liquid in the tank.

Alain Conde Reiss | alfa
Further information:
http://www.esa.int/SPECIALS/Launchers_Home/SEMLEZ0XDYD_0.html
http://www.esa.int

More articles from Studies and Analyses:

nachricht Drone vs. truck deliveries: Which create less carbon pollution?
31.05.2017 | University of Washington

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>