Designing your data center’s digital twin
Our Data Center projects :
External CFD simulation for data centers
EOLIOS is an expert in heat dissipation for data centers
- Study of thermal plumes
- Validation of maximum air temperature at equipment inlet
- Selection of equipment adapted to climatic conditions
- Study of critical failure scenarios
- Identification of bypass and recirculation air flows
- Generator impact study
- Energy optimization
- Validation of installation layout
- Optimizing placement and control of air handling systems
- Tailor-made solutions
EOLIOS is a leader in external CFD simulation for Data Centers. Our studies are based on feedback from measurement campaigns in real-life conditions and from a hundred or so simulated sites around the world.
Why run an external CFD simulation of a data center?
Study the heat dissipation of rooftops
Whether in the courtyard or on the roof, mechanical heat rejection systems such as cooling towers and DRYs share space with emergency generators. A compact, high-density layout of server racks inside the building translates into a compact layout of outdoor equipment. This leads to significant challenges and problems in managing the airflow outside the building.
External CFD studies are used to complete the risk assessment, optimize the design and reduce the energy consumption of the data center.
Schematic diagram of an adiabatic air cooler.
The influence of wind and weather on data center performance
The impact of thermal plumes outside the building is difficult to predict due to the various variables that design engineers and architects are unable to control. These variables include wind speed, air temperature and humidity, wind direction and other activities surrounding the building. However, these phenomena have an impact on the performance of equipment positioned outdoors.
EOLIOS can help you study the impact of these issues to ensure optimal operation in all circumstances, even the most extreme.
Modeling wind-driven thermal plumes on a data center roof
Why run an external CFD simulation of a data center?
Design validation under extreme conditions
These simulations provide results that aid data center owners and designers in the decision-making process by determining cost-effective layouts and performance. CFD analysis, when carried out before the design is finalized and implemented, helpsmitigate the risks associated with design errors, which can lead to costly and extensive modification requirements, construction delays or even loss of design capacity in the event of a critical failure during a heat wave.
"Is your data center protected against climate system failure during a heatwave? "
Systems suitable up to a certain temperature level
Most manufacturer’s equipment documents provide minimum clearance requirements for air conditioning equipment typically positioned on the roof. While this information is provided as a guide, it is expected that designers will consider these parameters in the layout of the machines.
The manufacturer’s recommendations on equipment installation are generally included: minimum distance between systems, maximum operating temperature, etc.
However, these guidelines do not take into account ambient air conditions, wind speed or the nearby built environment.
The figure below shows how adhering to the manufacturer’s recommended minimum distances can still result in undesirable performance.
A detailed model that adapts to different scenarios
We create a detailed computer model including surrounding buildings, all cooling devices on data center roofs, all exhausts, fresh air intakes and details such as windscreens, louvers and roofs…
We then use this model to study airflow, temperature distribution and water vapor (relative humidity) in several scenarios. These scenarios vary depending on the operational mode (normal, maintenance, emergency) and the weather conditions (high or low temperature, wind speed and direction).
Illustration of thermal plumes in several data center buildings, during a heatwave, and during an emergency restart of generator-type systems.
Study of the interaction of rooftop air-conditioning systems in relation to wind conditions
The hot air exhausted through the chimney flues is composed of the generator fumes and the air superheated by the heat exchange batteries. These airflows are blown back into the building by the wind, which causes heat to be recirculated through the roof systems.
As a result of these conditions, the ambient air temperature range at the inlet to the mechanical air-conditioning equipment may fall outside the manufacturer’s recommended operating range. These phenomena can lead to a loss of power or even the stopping of certain equipment.
CFD analysis allows us to understand how several systems will interact with each other. The video below shows the impact of the exhaust air (thermal plume) of generators in relation to the air conditioning equipment on the roof.
Defining power losses under extreme conditions
The mutualization of systems, the superposition of server halls, the continuous increase in power of the server racks leads to an extremely high dissipation of calories on the roof. The dissipation surface being constrained by the dimensions of the building, the result is a very high concentration of air conditioning systems on the roof, leading to a significant risk of power losses, or even cascading of systems during extreme climatic conditions.
In very hot weather, or in the event of a power cut on the site, plumes of overheated air generated by the cooling systems can lead to a sharp drop in cooling power, or even a cascade shutdown of the roofing systems, resulting in a site-wide fault.
Outdoor CFD studies for data centers enable us to study the risk of power loss and optimize the layout of rooftop cooling systems.
Study of pollutant emissions - Nox from generators
At the same time, it is possible to check that the exhaust fumes (Nox) from the generators are not taken up by rooftop AHUs, which would lead to air pollution in the offices.
External multi-criteria CFD for a data center
What use is internal CFD simulation for data centers?
Interior CFD modeling is typically used at the design stage for facility sizing analysis. Computer simulation provides information on the relationship between the operation of air conditioning systems and changes in the thermal load of computer equipment. With this information, IT and site personnel can optimize airflow efficiency, remove hot spots and maximize cooling capacity.
