MENUBlog contributed by Raja Olimuthu, Tecplot Business Development Manager
FPSOs: An Engineering Marvel
Floating Production, Storage, and Offloading (FPSO) vessels are some of the most complex machines on the ocean and are the workhorses of deepwater oil and gas projects. They extract, process, store, and offload hydrocarbons from subsea wells, often in locations where fixed platforms are cost-prohibitive or just technically unfeasible.
Instead of building massive, fixed platforms in deep water, operators often turn to FPSOs because they’re mobile and designed to stay in the field throughout the design life. FPSOs are used to facilitate production in fields without subsea export infrastructure. This makes them extremely versatile and valuable in the Oil and Gas industry. Some FPSOs are converted from old oil tankers, others are built from scratch.
FPSOs Serve 3 Primary Functions:
- Production – getting hydrocarbons out from the subsea wells, and separating them into oil, gas, and water
- Storage – holding crude oil onboard in huge tanks until it can be offloaded
- Offloading – transferring the stored crude on to shuttle tankers, which are then transported to refineries
With the versatility of an FPSO comes extraordinary design complexity, requiring engineers to address hydrodynamic loads, stability, and safety under extreme offshore conditions.
Where CFD Fits In
Computational Fluid Dynamics (CFD) is central to addressing these challenges. Applications include:
- Hydrodynamic Behavior and Mooring Loads
CFD helps simulate the interaction of waves, wind, and currents with the FPSO. With this data, engineers can predict how the vessel will move – up and down, side to side, and even tilting or twisting in different directions. These predictions help them understand how much strain the anchor lines and risers should handle, and make sure the vessel stays safely in place.
- Green Water and Slamming Events
When the sea gets rough, it can lead to two related but distinct phenomena. Green water events occur when waves overtop the deck of an FPSO, causing water to wash across the deck and threaten equipment and safety. Slamming events, on the other hand, happen when waves impact the bow or sides of the FPSO with high force. CFD simulations can help predict both types of events, informing design decisions such as the placement of barriers to protect critical equipment.
- Offloading Operations
Once extracted, the oil from the FPSO is transferred to a shuttle tanker. The relative motion, line tensions, and wave-induced interactions between the two vessels must be carefully evaluated to ensure safe and efficient offloading. These analyses are often performed using lower-fidelity motion models, with CFD applied when higher accuracy or more detailed flow behavior needs to be captured. The resulting insights help improve both safety and efficiency in crude transfer operations.
- Flow Assurance
CFD helps engineers predict problems like wax or ice-like blockages forming inside pipelines that connect the FPSOs to the wells on the seafloor. It can also help with the complexity of multi-phase flow (oil, gas, and water) through the pipes.
- Hydrocarbon Processing
The raw hydrocarbons that are extracted from the wells need to be processed into safely stored oil and gas. CFD is used to optimize all the different parts of this process.
- Blast Analysis
Crucial safety process that models how a potential gas explosion would affect the structure and equipment.
The MARIN study (Yoo et al., 2022) highlights how CFD can predict wind loads on FPSOs and shuttle tankers in side-by-side offloading operations, validating results against wind tunnel tests. Such research provides engineers with confidence in CFD’s predictive power for offshore operability. https://www.mdpi.com/2077-1312/10/5/654.
Making Sense Of This Data
Running CFD for FPSO design generates enormous datasets. Making sense of this information requires tools that can turn numbers into insight. One of the most valuable parts of the CFD workflow is understanding what all that output means and using it to make design calls.
With Tecplot 360, and its PyTecplot (Tecplot’s Python API) capabilities, you can repeat analyses across design iterations, ensuring results are both accurate and reproducible. If you’re working with data from different solvers or even experimental results, it gives you a way to put everything on the same page and compare them directly.
FieldView complements this by handling large datasets. It was built for HPC (High Performance Computing) work and parallel performance, so if you’ve got dozens of runs to compare, it won’t choke. Its realistic rendering capabilities allow engineers to present findings clearly to multidisciplinary teams, bridging the gap between simulation and decision-making.
Together, Tecplot 360 and FieldView give engineers the clarity needed to evaluate complex CFD results and confidently guide FPSO decisions.
MARIN’s research provides a clear demonstration of this. The MARIN team used CFD and experimental comparisons to examine wind loads on FPSOs and shuttle tankers. Using tools like Tecplot and FieldView, engineers can help:
Visualize the pressure on the FPSO surface.
Understand the wake turbulence and vortical flow structures around the FPSO.
Wrapping Up
FPSOs represent some of the most complex engineering systems today. CFD makes it possible to simulate and predict performance under challenging offshore conditions. But running the simulations is only half the battle – visualization is what unlocks meaning.
With Tecplot 360 and FieldView, engineers can automate, compare, and communicate CFD results effectively. Combined with research from institutions like MARIN, these tools help transform raw data into insights that drive safer, more efficient FPSO design.