Fluid Structure Coupling Technology
mechanical and fluid systems
Fluid Structure Coupling Technology (MFS-TOPS-2)
Passive method controls coupling between fluids and structures to disrupt and/or control the dynamics of a structure
Overview
NASA's Marshall Space Flight Center's Fluid Structure Coupling (FSC) technology is a highly efficient and passive method to control the way fluids and structures communicate and dictate the behavior of a system. This technology has the demonstrated potential to mitigate a multitude of different types of vibration issues and can be applied anywhere where internal or external fluids interact with physical structures. For example, in a multistory building, water from a rooftop tank or swimming pool could be used to mitigate seismic or wind-induced vibration by simply adding an FSC device that controls the way the building engages the water.
The Technology
FSC is a passive technology that can operate in different modes to control vibration:
Harmonic absorber mode: The fluid can be leveraged to act like a classic harmonic absorber to control low-frequency vibrations. This mode leverages already existing system mass to decouple a structural resonance from a discrete frequency forcing function or to provide a highly damped dead zone for responses across a frequency range.
Shell mode: The FSC device can couple itself into the shell mode and act as an additional spring in a series, making the entire system appear dynamically softer and reducing the frequency of the shell mode. This ability to control the mode without having to make changes to the primary structure enables the primary structure to retain its load-carrying capability.
Tuned mass damper mode: A small modification to a geometric feature allows the device to act like an optimized, classic tuned mass damper.
Benefits
- Passive device
- Minimized size and weight, since FSC devices can leverage existing fluids in and around the system
- Inexpensive: easy to retrofit to existing fluid systems
- Reduced complexity as control is achieved with a single fluid source
- Highly efficient, achieving complete control of the phase lag between fluid and structure
Applications
- Structural: Multistory buildings, stacks, towers, bridges, pools for spent nuclear fuel
- Oil and gas: Offshore oil rigs, above-ground storage tanks
- Municipal: Water tanks/towers
- Marine: Multi-directional stabilization of vessels or platforms
Technology Details
mechanical and fluid systems
MFS-TOPS-2
MFS-32903-1-CIP
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