Tension Leg Platforms (TLPs) are one of the best options for offshore industry in deep waters due to proven motion response characteristics. These are water depth sensitive structures and the motion responses in vertical plane motions (heave, roll and pitch) are critical for a TLP. Tension Based TLP (TBTLP) is a new concept and finds application in much deeper waters. A provision of a tension base at mid-depth results in an economical design of TLP. In fact, the TLP installed at a certain depth without any modifications can be made to be deployed in much deeper water depths by means of a tension base. In this paper, the concept of TBTLP is highlighted and hydrodynamic analysis of the chosen platform has been carried out using ANSYS AQWA package. The motion responses in terms of Response Amplitude Operators (RAOs) of TBTLP with one Tension Base in surge, heave and pitch have been obtained and compared with a TLP without a tension base. Copyright © 2012 by ASME.

R. Panneer Selvam

Department of Ocean Engineering

D. S. Bhaskara Rao

Nagan Srinivasan

ECONOMICAL DESIGN

HYDRODYNAMIC ANALYSIS

MOTION RESPONSE

OFFSHORE INDUSTRY

RESPONSE AMPLITUDE OPERATOR

SENSITIVE STRUCTURE

Vertical plane

water depth

ARCTIC ENGINEERING

Hydrodynamics

TENSION-LEG PLATFORMS

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Hydrodynamic Analysis of Tension Based Tension Leg Platform

Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE

Tension Leg Platform (TLP) is a hybrid structure used as oil drilling and production facility within water depths of 1200 m. The extension of this TLP concept to deeper waters is a challenge and warrants for some innovative design concepts. In this paper, a relatively new concept of TLP which is christened as Tension-Based Tension Leg Platform (TBTLP) and patented by Srinivasan (1998) has been chosen for study. Response analysis of TLP with one tension base under irregular waves for three different sea states has been performed using hydrodynamic tool ANSYS® AQWA™. Results are reported in terms of RAOs, response spectrums for surge, heave and pitch degrees of freedom from which spectral statistics have been obtained. The statistics of TBTLP have been compared with TLPs (without tension base) for two different water depths to highlight the features of the new concept. The effect of viscous damping and loading effects on the RAOs are also investigated. © 2016, Chinese Ocean Engineering Society and Springer-Verlag Berlin Heidelberg.

China Ocean Engineering

Response analysis of tension-based tension leg platform under irregular waves

Tension Leg Platforms (TLPs) are one of the reliable structures in the offshore industry in deep waters because of its motion characteristics in heave, roll and pitch degrees of freedom (dof). Heave motion is very important in offshore facilities and have to be kept as minimum as possible. As the water depth increases TLPs suffers from some limitations and hence has to be modified to cater to deeper waters. One such concept proposed is Tension Based Tension Leg Platform (TBTLP). In this paper, experimental investigations carried out on a 1:150 scaled model of a Tension Based Tension Leg Platform in regular waves in 3 m water depth is reported. These are the first ever experiments which were carried out on a scaled model of the new concept. To investigate the effects of Tension Base, experiments were also conducted on the TLP (without Tension Base). Responses have been compared in terms of Response Amplitude Operators (RAOs) for surge, heave and pitch dof for TBTLP and TLP. Numerical modeling of the TLP and TBTLP responses using ANSYS® AQWA™ software is included as well for comparisons. © 2014 ANAME Publication. All rights reserved.

Fulltext

Journal of Naval Architecture and Marine Engineering

Experimental investigations on tension based tension leg platform (TBTLP)

The role of mini tension leg platforms (TLP) in oil exploration and production in marginal deepwater fields is becoming increasingly important. SeaStar is a mini TLP that combines the simplicity of a spar and favourable response features of a TLP. In this paper, the results of a detailed numerical investigation of the coupled dynamic behaviour of SeaStar are reported with special attention to platform-tether coupling. The numerical study has been carried out using a finite element computer code developed for the nonlinear dynamic analysis of compliant offshore platforms in the time domain using Morison type wave loading. A typical SeaStar platform has been considered at two water depths, 215 m and 1000 m. Experimental investigation was conducted for a scaled model corresponding to 215 m water depth for validation of the numerical model. The model-prototype correlation studies have been conducted using the numerical model. Response amplitude operators of motion and tether tension are presented for the two typical water depths and conclusions drawn. © 2002 Elsevier Science Ltd. All rights reserved.

Journal	Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE
Open Access	No