A dry tree floating platform accommodates Top Tension Risers (TTRs) within the well bay in the center of the platform. The reservoir size dictates the number and size of TTRs required and determines the minimum well bay layout and size. In addition to the platform motions, the TTR and its connecting jumper motions, which occur due to environment loading, influence the minimum riser spacing in the well bay. An optimum well bay layout is a key component in the efficient design of a floating platform.
Because the TTRs and jumpers, supported by a floating platform, experience different dynamic responses, a range of dynamic analyses is required to assess the performance of the entire system. This study considers several different environmental conditions in the Asia Pacific region and performs dynamic analyses of riser systems and jumpers to create optimized well bay layouts for several small-scale Tension Leg Platforms (TLPs). Commercial and in-house design tools have been used in this study. The in-house tool is effective for quick sizing of well bays for conceptual studies.
It is observed that the TTR and jumper motions vary considerably with environmental conditions. The results from the in-house tool facilitates the dynamic analysis using commercial software. The results of this study demonstrate the influence of riser analysis for well bay layout and sizing; i.e. riser system motions should be estimated to a reasonable level of accuracy at an early design stage to facilitate effective detailed design of the topsides and floating platform.