Picture of a black hole

Strathclyde Open Access research that creates ripples...

The Strathprints institutional repository is a digital archive of University of Strathclyde's Open Access research outputs. Strathprints provides access to thousands of research papers by University of Strathclyde researchers, including by Strathclyde physicists involved in observing gravitational waves and black hole mergers as part of the Laser Interferometer Gravitational-Wave Observatory (LIGO) - but also other internationally significant research from the Department of Physics. Discover why Strathclyde's physics research is making ripples...

Strathprints also exposes world leading research from the Faculties of Science, Engineering, Humanities & Social Sciences, and from the Strathclyde Business School.

Discover more...

Instability of a vertical riser in the wake of an upstream vertical riser

Huang, Shan (2010) Instability of a vertical riser in the wake of an upstream vertical riser. Applied Ocean Research, 32 (3). pp. 351-357. ISSN 0141-1187

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

The static solution and its associated dynamic stability of a vertical riser situated in the wake of an upstream riser is investigated in the paper. Both the upstream and downstream risers are top-tensioned and pinned at the bottom ends on the seabed. Due to the wake effects, the downstream riser is subject to mean lift force as well as drag along its length. It is shown that under certain current conditions there exist multiple stable and unstable static solutions of the downstream riser. There also exists a critical current velocity and once this velocity is exceeded no static solutions of the downstream riser can be found. The disappearance of the static solutions is closely related to the loss of stability which is believed to be the main cause of ensuing clashing between the two risers. A further dimensional analysis reveals that the instability onset criteria can be described by three nondimensional parameters.