Water Hammer Test Laboratory Bremen – impulse load and pressure cycle investigations on critical subsystems and components for aircraft, spacecraft and launch vehicle propulsion systems
- Paper number
IAC-11,C4,3,19,x10831
- Author
Mr. Torsten Bolik, machttechnik.de AG, Germany
- Coauthor
Mr. Carsten Holze, machtwissen.de AG, Germany
- Coauthor
Dr. Martin Meier, machttechnik.de AG, Germany
- Coauthor
Dr. Philipp Behruzi, Astrium, an EADS Company, Germany
- Coauthor
Dr. Nicolas Fries, Astrium, an EADS Company, Germany
- Year
2011
- Abstract
The ´Water Hammer Test Laboratory´ operated by machtTechnik AG in Bremen, Germany is engaged in impulse and cycle load examinations appearing in space- and aircraft propulsion systems. E. g. a sum of transient pressure test series commissioned by Astrium GmbH an EADS company was done successfully and will be continued. The ´Water Hammer´–phenomenon is an impulse load occurring in pipe flow of fluids. For example, it can be caused when a liquid in motion is forced to stop or change direction suddenly. In most practical cases, liquids can be regarded as incompressible and changes in pressure are transmitted with the speed of sound. The pressure often changes very dynamically e.g. when a valve in the loop is closed quickly. This causes a backward propagating over-pressure in the pipe system which stresses all subsystems like valves, filters and may jeopardize the performance of further devices in the installation loop. These transient fluid flow effects can have a significant influence on the operation of propulsion systems of spacecraft and launch vehicle. Water Hammer effects may occur at systems priming, activation and shut down, and even can induce sloshing effects in the propellant tank. Due to the hazardous character of propellants of spacecraft propulsion systems it is very intricate to do investigations as part of the complete system in a test setup. Therefore, a project of this kind would have to rely on best available technology and engineering, should be performed in a safety shell and then hope for the best. Our approach was to reduce the complex boundary conditions in spacecraft propulsion systems for dedicated impulse load and pressure cycle investigations by using simplified engineering models. Therefore, it was possible to perform meaningful fatigue and stress tests on complete pipe/valve/regulator/vessel installations and subsystems or single components more easily. Some ´Highlights´ of the testing work by machtTechnik AG and actual test results by Astrium will be presented: \begin{itemize}\item By an extremely tough engineered Water Hammer generator realistic dynamic effects of propulsion systems could be simulated by using ultra-pure degassed water as a model fluid.\end{itemize} \begin{itemize}\item The pressure unit allowes the application of pressure cycles with a static pressure up to Pstatic=25 bar and additional dynamic pressure cycles of up to ΔP=50 bar.\end{itemize} \begin{itemize}\item For life time fatigue tests of special components test rates of more than 500.000 Water Hammer cycles per 24 hours are possible.\end{itemize} \begin{itemize}\item Sophisticated real time experiment data recording.\end{itemize}- Abstract document
- Manuscript document
(absent)