ANCIS Incorporated, a San Francisco based consultancy, recently helped a major telecom firm develop a greatly improved heating, ventilating, and air-conditioning (HVAC) design standard for its central offices (COs) using Flomerics' FloVENT computational fluid dynamics (CFD) software to predict air intake temperatures for sensitive electronic equipment. Based on these intake temperatures, the Rack Cooling Index (RCI) algorithm developed by ANCIS was used to calculate the compliance of alternative designs with industry temperature specifications. "FloVENT's robust and predictable performance helped us to optimize equipment reliability in our client's COs," said Dr. Magnus K. Herrlin, Founder and President of ANCIS.
"Thermal challenges in central offices and data centers are one of the most serious threats to equipment reliability," Herrlin said. ANCIS has addressed this challenge by using FloVENT and the RCI sequentially to provide a quick but comprehensive way to compare cooling performance for alternative HVAC designs. An RCI of 100% means ideal conditions with the air intake temperatures to all equipment racks within the temperature specifications. Since it is not possible to achieve ideal conditions in most real world situations, it's important to have a metric that can quickly compare the relative performance of different designs.
The telecom firm approached ANCIS to help develop a new HVAC standard for their central offices, which not only have a high average heat density but also large variations in densities. ANCIS engineers developed several designs utilizing various air distribution concepts such as a raised floor and overhead cooling. They modeled each design in FloVENT by duplicating the geometry of each proposed CO design and defining the amount of heat generated by each piece of equipment. They modeled the supply air velocity and temperature as well as the physical locations of the supplies and returns.
ANCIS engineers used monitoring points at each air inlet to track rack intake temperatures for each piece of equipment. These numbers were used as input to the RCIHI and RCILO algorithms which determine, respectively, whether equipment experiences temperatures above the maximum and below the minimum recommended temperatures. These indices provide measures of how effectively racks are cooled and maintained within industry temperature guidelines or standards. The data were used by the management of the telecom company to evaluate the alternative designs provided by ANCIS. They selected a design that provided an excellent RCI of close to 100%.
"I have been using FloVENT for 10 years starting when I was working at Bell Communications Research," Herrlin said. "FloVENT's consistent performance has made it possible to automate the process of evaluating the thermal performance of telecom and data centers using the RCI. The RCI provides a standardized way of communicating the thermal performance of various cooling designs in a two part index that is easily understood. Thanks to FloVENT, we can produce this information in a very short time."
For further information, please contact:
Head of Marketing
Mentor Graphics Mechanical Analysis, UK
81 Bridge Road
Surrey, KT8 9HH
Tel: +44 (0)20 8487 3000
Fax: +44 (0)20 8487 3001