Abstract
This case study aims to cover a wide range of relevant aspects related to combined cycle design, mechanical
integrity and operational reliability for cogeneration of heat and power in FPSO systems. The methods consist of
combined optimization of combined cycle thermodynamic design and geometry of steam generator; vibration
analysis for flow induced vibrations; and thermal stress estimation of casings during cold start-stop scenarios.
Challenges and opportunities for reliable water treatment systems are explored. The results show that small
tubes, a compact tube bundle and a low condensation temperature reduces the once-trough steam generator
(OTSG) weight. The vibrations numerical simulations in this work support the standard recommendations of
using 35 times tube OD as upper limit for the unsupported tube length, which could be used as a reasonable
design criterion. Thermal stresses analysis indicates that the design of beam arrangement, location, and stiffness
of beams has a major impact on thermal stresses, and can be optimized to different plate thicknesses in order to
avoid fatigue damage. Focus should be on reducing leaks of deaerator, steam turbine and condenser. It is recommended to add Na sensors after condenser and investigating the use of Electrodeionization (EDI) technology
for make-up water production from seawater.
integrity and operational reliability for cogeneration of heat and power in FPSO systems. The methods consist of
combined optimization of combined cycle thermodynamic design and geometry of steam generator; vibration
analysis for flow induced vibrations; and thermal stress estimation of casings during cold start-stop scenarios.
Challenges and opportunities for reliable water treatment systems are explored. The results show that small
tubes, a compact tube bundle and a low condensation temperature reduces the once-trough steam generator
(OTSG) weight. The vibrations numerical simulations in this work support the standard recommendations of
using 35 times tube OD as upper limit for the unsupported tube length, which could be used as a reasonable
design criterion. Thermal stresses analysis indicates that the design of beam arrangement, location, and stiffness
of beams has a major impact on thermal stresses, and can be optimized to different plate thicknesses in order to
avoid fatigue damage. Focus should be on reducing leaks of deaerator, steam turbine and condenser. It is recommended to add Na sensors after condenser and investigating the use of Electrodeionization (EDI) technology
for make-up water production from seawater.
