By Adamines | November 25, 2021 | Category: IT news
Room level airflow management is often the least understood aspect of airflow management in data centers, despite being the most crucial. While the first three levels of airflow management (Raised Floor, Rack, and Row) involve implementing physical solutions, the Room level is more about cooling optimization through adjustments to cooling system controls.
Understanding Room Level Airflow Management
Room level airflow management, better defined as cooling optimization, involves making adjustments to the cooling system controls. When done correctly, this process can:
- Improve energy efficiency (reducing operating costs)
- Enhance cooling capacity
- Improve IT equipment reliability
- Defer capital expenditure
It's important to note that without cooling optimization, the solutions implemented at the Raised Floor, Rack, and Row levels remain mere expenses. The financial and capacity benefits are only realized through proper Room level airflow management.
Matching Cooling Capacity with IT Load
Airflow management alone doesn't save money on cooling energy costs. Instead, it creates conditions where changes to the cooling infrastructure become possible. After implementing airflow management solutions at the first three levels, you should have an excess of conditioned supply air in your cold aisles, resulting in excessively low IT equipment intake air temperatures.
The next step is to match the flow rate of conditioned air as closely as possible with the demand flow rate required by the IT equipment. This is achieved by:
- Lowering fan speeds
- Raising cooling unit temperature set points
- Turning off cooling units altogether
Room Level Airflow Management Best Practices
- Reduce fan speeds for units with variable frequency drives (VFDs) as much as possible without exceeding the maximum allowable IT equipment intake air temperature.
- Raise cooling unit temperature set points as high as possible without exceeding the maximum allowable IT equipment intake air temperature.
- Expand the allowable relative humidity (Rh) band to prevent cooling units from "fighting" with each other.
- Turn off excess cooling if cooling units don't have VFDs.
Note: If cooling units are equipped with VFDs, energy savings are greater with 10 cooling units running at 50% fan speed than 5 cooling units running at 100% fan speed.
Utilizing Monitoring Solutions
Monitoring solutions are crucial in the cooling optimization process. They help in:
- Balancing power demand (IT load) with cooling supply (cooling capacity)
- Monitoring IT equipment intake temperatures to ensure they don't exceed recommended or allowable limits
- Providing a site-wide view of the data center's thermal performance
Some advanced monitoring solutions offer 3-D visualizations, displaying a digital twin of your data center and its real-time thermal performance.
Optimization with AI and Machine Learning
AI and Machine Learning technologies are proving valuable in airflow management and cooling optimization. They can help:
- Visualize airflow management improvements at all levels
- Analyze data collected from sensors
- Provide advisement on cooling optimization decisions
Some solutions couple monitoring with cooling optimization in the form of a virtual cooling advisor, taking some of the guesswork out of the process.
Conclusion
Room level airflow management, or cooling optimization, is a necessary step to realize energy savings from airflow management improvements made at other levels. It's an iterative and ongoing process that matches cooling capacity with the IT load of the computer room.
Remember, efficiency cannot be purchased; it must be managed. While cooling optimization is often a manual process, utilizing monitoring solutions that provide insights into power, cooling, and thermal performance can guide your optimization decisions and, in some cases, advise on specific steps to take.