White Paper December 2015 WP-24 Panduit Net-Access™ Cabinet Doors Keep Data Center Equipment Cool and Secure Key Points: How does the magnitude of airflow restriction impact the operation of typical IT equipment? Are the effects significant? Can we determine the effect that the door perforation pattern has on preventing access to the IT equipment?
Panduit Net-Access™ Cabinet Doors Keep Data Center Equipment Cool and Secure Overview Data center equipment cabinets are provided with front and rear doors for aesthetics and security. A potential tradeoff of installing cabinet doors is any negative impact that the doors may have on the flow of air that must be drawn through the cabinets to cool the equipment housed inside.
Panduit Net-Access™ Cabinet Doors Keep Data Center Equipment Cool and Secure Figure 1. ANSI/BICSI 002-2014 Airflow Capacity. Effect of perforation % open area on AFCD for Panduit Net-AccessTM 42 RU cabinets. Figure 1 shows that wider cabinets, which have more perforated area on the doors, require a lower percent open area of perforation pattern to meet the minimum AFC D requirement.
Panduit Net-Access™ Cabinet Doors Keep Data Center Equipment Cool and Secure Figure 2. Panduit Net-Access™ door and perforated sheet samples tested. Test Method The Airflow Laboratory used an ANSI/AMCA 210-99 compliant test chamber and fabricated a 20inch (50.8 cm) square cross section duct with pressure measurement tubes installed on both sides of the test samples (Figure 3). Pressure drop was measured across the samples at a variety of airflow rates.
Panduit Net-Access™ Cabinet Doors Keep Data Center Equipment Cool and Secure Airflow Test Results and Analysis Figure 4 shows airflow resistance curves from the test results for the perforated sheet samples and for a Panduit perforated door. As expected, higher percent open area samples had lower resistance to airflow. Figure 4. Perforated sample flow testing results through a 20-inch square duct.
Panduit Net-Access™ Cabinet Doors Keep Data Center Equipment Cool and Secure Figure 5. Server airflow performance curves. These curves show how the airflow through a server, shown on the horizontal axis, is reduced by the presence of a resistance, represented as a static pressure on the vertical axis. Notice that both server airflow curves (Figure 5) and perforation flow test curves (Figure 4) use the same units on both axes.
Panduit Net-Access™ Cabinet Doors Keep Data Center Equipment Cool and Secure Figure 6. 9 RU server airflow curve and perforated door resistance curves. The intersections of the curves are the key to interpreting the graph depicted in Figure 6. The point where the server airflow curve intersects the horizontal axis shows the server airflow through a cabinet with no doors, and therefore no airflow restrictions.
Panduit Net-Access™ Cabinet Doors Keep Data Center Equipment Cool and Secure Table 1. Perforated door airflow reduction and resulting increase in exhaust temperature. 600 mm Cabinet Perforated Door % Open Area 57% 69% 80% Servers Airflow Exhaust Airflow Exhaust Airflow Exhaust [qty] type reduction ∆T reduction ∆T reduction ∆T [42] 1 RU servers 1.8%* 0.33°C <0.1% 0.21°C <0.1% <0.1°C [21] 2 RU servers 0.4%* 0.06°C <0.1% 0.04°C <0.1% <0.1°C [4] 9 RU servers 2.8% 0.26 C 1.0% 0.09°C 0.2%* 0.
Panduit Net-Access™ Cabinet Doors Keep Data Center Equipment Cool and Secure Figure 7. Force required to penetrate perforated patterns with a #2 Phillips screwdriver. The data shows that as the percent open area of the perforated pattern increases from 57% to 69%, the force required to penetrate the pattern decreases by 24%. An increase to 80% open area reduces the force required to half of the 57% open area pattern’s required force.
Panduit Net-Access™ Cabinet Doors Keep Data Center Equipment Cool and Secure Evaluation of airflow test results compared to actual server operating conditions showed that the real effect of perforation pattern percent open area on the equipment is minimal over the relatively wide range of percent open areas tested.
Panduit Net-Access™ Cabinet Doors Keep Data Center Equipment Cool and Secure About Panduit Panduit enables data centers to realize their full potential through an integrated stack of physical and intelligent infrastructure solutions that drive actionable performance gains and efficiencies to reduce operating costs and maximize capacity of power, cooling, space, and connectivity for the greatest ROI.
