The project "Simulation of Buffer Vessels for Data Centres", delivered for Meit Consultants LLP in 2024, addressed a practical data-centre engineering challenge through computational fluid dynamics (CFD). Rather than producing simulation images in isolation, the study was organised around the client's design questions: what controlled performance, where the principal risks or losses occurred, and how the design or operating strategy could be improved.

We improved temperature stability and resilience in chilled water systems by optimising buffer vessel geometry, inlet and outlet design and control for data centres. A computational fluid dynamics model of the tank resolved stratification, short-circuiting risk and recharge efficiency across transients representative of load steps and chiller cycling. Nozzle orientation, diffuser elements and internal baffles were varied to quantify their impact on mixing and effective volume. Key performance indicators included temperature uniformity at supply and return, head loss and time to recover after a disturbance. Mesh and solver checks ensured robust trends, and parametric sweeps produced response maps that translate directly into engineering choices. Layouts were identified that stabilise supply temperatures and limit mixing during recharge without undue pressure drop, supporting reliable operation at low approach temperatures. The outcome was an implementation ready set of design changes and a reusable model to inform commissioning and future capacity increases in data-centre deployments.

The methodology centred on a transient thermal CFD model of the chilled-water buffer vessel through discharge and recharge. The representation retained the tank, inlet and outlet nozzles, internal volume and any diffuser or baffle features that govern stratification, short-circuiting and effective storage. Boundary and operating conditions covered the required five-minute cooling duty, load steps, chiller cycling and the subsequent recharge process, with material, fluid and equipment properties assigned from the available design information. Resolution was concentrated in regions where steep velocity, thermal, concentration or phase gradients were expected, while the overall model remained efficient enough to compare several credible configurations. This balance allowed system-level performance to be linked to the local mechanisms responsible for it.

The assessment compared nozzle position and orientation, diffuser elements and internal geometry changes. Performance was judged using outlet-temperature stability, usable thermal volume, mixing, stratification, head loss, discharge duration and recharge or recovery time. Results were reviewed through quantitative summaries and engineering visualisations, such as contours, vectors, streamlines, sections and time histories, selected to suit the physics. Important assumptions and operating uncertainties were considered so that the recommendations relied on repeatable comparative trends rather than a single nominal case.

For Meit Consultants LLP, the principal value was an implementation-ready vessel arrangement that improved data-centre cooling resilience and temperature stability. The final evidence linked each recommendation to the relevant model or process output, making it suitable for internal design reviews, supplier or contractor discussions and, where applicable, planning, safety or regulatory dialogue. The work also created a reusable baseline that can be updated as geometry, operating data or test results become available, reducing the cost and risk of later design iterations.