Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering Conference
Shanghai, China, June 5–10, 2022
Copyright © 2022 by the International Society of Offshore and Polar Engineers (ISOPE)
ISBN 978-1-880653-81-4; ISSN 1098-6189

www.isope.org

Experimental and Numerical Studies on Behavior of Rotating Model Drill Pipe in Uniform Flow
Hiroyoshi Suzuki,
Dept. of Naval Architecture and Ocean Eng., Osaka University, Suita, Osaka, Japan

Tomoya Inoue,
Institute for Marine-Earth Exploration and Engineering, JAMSTEC, Yokosuka, Kanagawa, Japan

Tokihiro Katsui,
Kobe Ocean-Bottom Exploration Center, Kobe University, Kobe, Hyogo, Japan

Ryota Wada,
Department of Ocean Technology, Policy and Environment, The University of Tokyo, Kashiwa, Chiba, Japan

Keita Tsuchiya,MODEC, Chuo-Ku, Tokyo, Japan

Yusuke Notani,
Honda Motor, Co., Ltd., Minato-ku, Tokyo, Japan

Keita Ishida, Taito Koga,
Dept. of Naval Architecture and Ocean Eng., Graduate School of Eng., Osaka University, Suita, Osaka, Japan

ABSTRACTIn this study, the underwater behavior of a model drill pipe rotatingin uniform flow was investigated through experimental and numericalanalyses. The hydrodynamic force acting on the rotating equipment ofthe model drill pipe was measured, and its coefficient was derived. The
displacement of the model drill pipe was also observed and measured.
The numerical estimation of the model’s displacement wasimplemented by applying computational fluid dynamics and absolutenodal coordinate formulation.

KEYWORDS: Underwater behavior, Model drill pipe, Magnus effect,
ANCF.

INTRODUCTION
In recent years, offshore drilling has become increasingly important
for the exploration of new resources (e.g., seafloor minerals andmethane hydrate) and scientific research, such as the elucidation of themechanism of earthquake occurrence. There are two types of offshore
drilling: riser drilling (in which riser pipes are connected to the seafloor
and hull of the vessel, and drill pipes pass through the riser pipes) andriser-less drilling (in which drill pipes are lowered directly into the sea).
Riser-less drilling is used for large-depth and shallow-depth drilling toovercome the operating depth limit of the riser, whereas riser-lessdrilling is used for riser drilling until a blowout preventer and riser pipe
are installed. For riser drilling, detailed measurements have been
conducted and reported for the 2000[m] length of actual riser assemblyin terms of riser pipe vibration caused by drilling (Blevins et al. 2017).
On the other hand, the interest of experiments and numericalsumulation for riser-less drilling is the drill pipe failure and fatigue
failure of the drill pipe due to impact forces and cyclic loading acting
on the drill pipe.(for example, Zaho et al.,2018)
In riser-less drilling, the drill pipe is directly exposed to the external
environment, and the drill pipe behavior becomes more complex. In1885

deep drilling, the drill pipe behavior becomes more complicated as thedrill pipe becomes longer, and the natural period of the drill pipe
approaches the predominant period of the ship motion. Although drill
pipe dynamics do not cause major problems in conventional drilling,
they affect the drilling operation. For example, the fluctuating axial
stress in the drill pipe caused by ship motion may be up to 10 times
greater than that in rigid body hypothesis due to the influence of drillpipe dynamics. Vortex excitation in tidal currents is complicated bydrill
piperotation;its
characteristics differ from those of
vortex excitation in a fixed pipe
(Inoue et al., 2013). Furthermore,
the drill pipe rotation in tidal
current generates a lift force
called the Magnus effect, which
deforms the pipe. These dynamics
may have contributed to thedamage and rupture of drill pipes
as well as to the disruption ofdrilling operations (Inoue et al.,2017a).
However, as shown in Fig. 1,
only the top 30 m of the drill pipe,
which is several thousands ofFig. 1 Drill pipe in operation
meters long, can be monitored.
Currently, inferring the drill pipe
deformation and behavior in water from the drill fluctuation andbehavior at the top 30[m] is impossible. Consequently, expectations arehigh for the estimation of drill pipe behavior using numerical analysis.
Here, the Magnus effect is described. Batchelor(1967) described that
“The existence of side-force on a rigid circular cylinder which is bothrotating and moving forward, and likewise on a sphere, is usuallyknown as the Magnus effect”. The use of the Magnus effect in ship andocean engineering includes, for example, the roll stabilizer for ships(Ozturk,2020) and the rotor ship(Nuttall, and Kaitu’u, 2016).