Precision Cooling Architecture Flashcards

In a hot aisle/cold aisle containment strategy, which containment approach captures exhaust air directly at the source and returns it to cooling units without mixing?

Answer: Hot aisle containment (HAC)

Hot aisle containment encloses the hot exhaust aisle, directing hot return air directly to cooling units and preventing it from mixing with cooled supply air.

Blanking panels installed in empty rack unit (RU) spaces serve which primary airflow management function?

Answer: Preventing hot exhaust air from recirculating to equipment air inlets

Blanking panels block gaps in racks that would allow hot rear exhaust air to bypass the equipment and recirculate back to the cold intake side.

In a raised-floor data center, what is the recommended minimum raised-floor plenum depth to ensure adequate static pressure for airflow distribution?

Answer: 24 inches (61 cm)

A minimum plenum depth of 24 inches is generally recommended to provide sufficient static pressure and uniform airflow distribution across perforated floor tiles.

Airflow short-circuiting in a data center occurs when:

Answer: Cold supply air bypasses IT equipment and returns directly to cooling units as cool air

Short-circuiting happens when cold air finds a path of least resistance back to the cooling unit without passing through server intakes, reducing effective cooling.

Which tool is most commonly used to measure and map airflow distribution and identify hot spots across a raised-floor data center?

Answer: Computational Fluid Dynamics (CFD) modeling software

CFD modeling simulates airflow, pressure, and temperature distribution in 3D, enabling engineers to identify hot spots and optimize cooling layout before physical changes.

Chimney cabinets (also called exhaust ducting cabinets) solve which specific airflow problem in high-density deployments?

Answer: They duct hot exhaust from individual racks directly to ceiling return plenums

Chimney cabinets attach to the top of racks and duct hot exhaust air directly up to the ceiling return plenum, preventing hot air from mixing with room air.

What percentage of perforated floor tile open area is recommended for use directly in front of high-density server racks in a raised-floor environment?

Answer: 56% open area tiles

Higher-density racks require 56% open-area tiles (or fully open grates) directly in front to deliver sufficient CFM without excessive pressure drop.