The acoustic impact on HDDs: risk mitigation measures
Tue 26 Dec 2017 | Alan Elder
Alan Elder, Tyco fellow, Tyco Fire Protection Products, looks at the research conducted on the impact of acoustics on HDDs and risk mitigation measures
Data centres are relied upon to store and distribute valuable information for customers across many industries, from the investment banking to the healthcare sector.
This valuable information is primarily stored on hard disk drives (HDDs). Industry demands that data centres remain functional 24 hours a day, 7 days a week, 365 days a year, and downtime can damage the reputation of a data centre or even a business, resulting in the loss of customer trust and subsequent business.
One way of reducing the risk of downtime or lost operation time is to minimise the impact of fire. These events have a significant effect on the operational viability of a data centre, and threaten the safety and security of its assets. Protecting against fire damage is a critical consideration when designing and operating a data centre in order to ensure maximum uptime and avoid unnecessary disruption and cost to recover from a fire event.
The impact of acoustic energy
Installing an inert gas fire suppression system is one option to provide effective protection for data centres. Yet understanding the application requirements is key. These systems have shown, through discharges in the field, that HDD performance may be reduced, or permanent damage may occur to this sensitive electronic equipment as a result of exposure to high acoustic levels.
To gain a greater understanding of the impact of acoustic energy on hard drives, Tyco Fire Protection Products (Tyco), conducted a holistic study of HDD performance with respect to acoustic energy, room acoustics, and suppression system nozzle acoustics.
The sound output of fire suppression systems is dependent on many factors. These include discharge duration, peak agent flow rate, valve technology and many others. Tyco performed extensive research and modelling of inert gas agent flow to develop an inert gas suppression nozzle with a low sound power.
Acoustic calculations
As a result of the acoustic research study, a novel tool has been developed for performing acoustic calculations for data centres
Tyco’s research, in collaboration with Michigan technological university, focused on the fact that every hazard area protected by a fire suppression system will yield varying sound path absorption properties.
Data centres should have room acoustic calculations performed to ensure the fire suppression system installation will meet the sound performance requirements to help reduce the risk of HDD degradation should the system discharge.
The sound pressure level calculation method requires the use of advanced acoustic formulas to determine the sound absorption between the fire suppression system nozzles and the HDDs.
As a result of the acoustic research study, a novel tool has been developed for performing acoustic calculations for data centres. Tyco’s acoustic calculator helps generate the acoustic calculations to estimate the sound pressure level at an HDD location generated by an inert gas suppression system using the Tyco acoustic nozzle.
The acoustic calculator simplifies the calculation by containing drop-down menus for the suppression system parameters, as well as selection of room materials and the equipment within the data centre. This enables Tyco’s technical services team to perform calculations tailored to each customer installation.
The Tyco acoustic calculator used in conjunction with its acoustic nozzle is a substantial advancement in addressing the acoustic challenges for the data centre market, providing an effective solution that can reduce sound exposure to sensitive HDDs and due to its extensive area coverage may enable the designer to use significantly fewer nozzles and piping.
Rigorous testing through hundreds of suppression system discharges offers superior sound power performance and suppression capabilities in comparison with standard suppression nozzles.
This post originated at Data Centre Management magazine, from the same publisher as The Stack. Click here to find out more about the UK’s most important industry publication for the data centre space.
