Dynamic response of tension leg platform with tuned mass dampers

Abstract

Tension Leg Platform (TLP) is a taut-moored compliant offshore platform that deploys tethers under high initial pretension to counteract the excess buoyancy. TLPs show large amplitude responses under the encountered lateral forces, which challenges the serviceability of the platform in critical sea states. One of the passive control device i.e. Tuned Mass Damper (TMD) is attempted in the present study to control large amplitude motion of TLPs. In the present study, response control of TLP using single and multiple TMDs is compared. Optimized parameters of multiple tuned mass dampers (MTMD) are obtained using H2 optimization algorithm for the maximum control of the motion of the platform. Based on the studies conducted, it is seen that MTMD systems show better response control in comparison to the single TMD. Higher robustness of the MTMD system is also examined to highlight the use of MTMD over a wide range of excitation frequencies in extreme sea states.DOI: http://dx.doi.org/10.3329/jname.v10i2.16184

Experimental investigations on tension based tension leg platform (TBTLP)

“…Scaling has been carried out by Froude law (Chakrabarti, 1994) and the prototype and model details of TLP are given in Table 1. The TLP consists of four square columns interconnected by a set of trusses at the top and bottom on all the four sides.…”

“…To use the TLP concept to deeper waters, researchers proposed modified TLP concepts such as Mini TLPs (Kibbee, 1996), Extended TLP (John., et al, 2009), Suspended TLP (Jagannadhan, 1992, Raft TLP (Abbott., et al, 1994), and Tension Based TLP (Srinivasan, 1998). Response control measures using tuned mass dampers to control the responses of TLPs have also been attempted (Chandrasekaran et al, 2013) instead of modifying the design. Detailed experimental and numerical investigations were carried out by researchers on the modified concepts.…”

The TLP 2-DOF as an alternative model for extreme wave application

“…Many designers have carried out many efforts to improve the design concept. Among them, modifying the TLP geometry to be triangular [9], adding and adjusting the mass of dampers [10], and proposing a new model of mooring system configuration [11], In addition, some propose a design for tension-leg twin platform structural systems [10], However, besides having advantages, those design concepts also have several weaknesses. For example, the Tension-leg twin platform structural systems design depends on the distance of the two pontoon and wavelength, which increases the resulting  Kapal: Jurnal Ilmu Pengetahuan danTeknologi Kelautan, 18 (2) (2021):80-87 dynamic response [13], For these reasons, this study will discuss a new design that is different from the previous designs, called the Tension Leg Platform of Two Degree of Freedom (TLP 2-DOF), which is relatively more stable to wave force.…”

Surge Motion Passive Control of TLP with Double Horizontal Tuned Mass Dampers

“…10 A simulationbased robust design of mass dampers for response mitigation of TLP was presented by Taflanidis et al 11 Chandrasekaran et al studied the dynamic response behavior of a multi-legged articulated tower with and without TMD. 12 Also dynamic response of TLP with tuned mass dampers was examined by Chandrasekaran et al 13 Chatterjee and Chakraborty (2014) conducted a survey on vibration mitigation of structures subjected to random wave forces by liquid column dampers. 14 This paper focuses on vibration mitigation of TLP in a horizontal direction.…”