3 October 2017

New heat exchanger to keep magnets chill

Workers offload the MagLab's new 35,000-pound heat exchanger. Workers offload the MagLab's new 35,000-pound heat exchanger.

In the past year the National MagLab has unveiled two world-record magnets, the 36-tesla series connected hybrid magnet and the 41.4-tesla resistive magnet.

These top-notch magnets require a top-notch infrastructure. So later this year, lab staff will install a new heat exchanger to keep up with the demands of its boundary-pushing instruments.

"We're trying to upgrade everything as the lab upgrades," explained plant engineer Tra Hunter. "The magnets are getting bigger and requiring more cooling water."

Magnets in the lab's DC Field Facility are powered by as much as 32 megawatts (MW) of electricity each and generate the heat to match. A complex array of pipes, chillers, heat exchangers, chilled water storage tanks and cooling towers keeps the instruments from overheating by flushing them with thousands of gallons of cold, de-ionized water a minute.

The new 35,000-pound heat exchanger features a stack of nearly 600 8x4-feet stainless steel plates. Warm water from the magnets flows in through one pipe and zigzags through alternating plates; chilled water flows in another pipe, snaking its way through the second set of plates. The cooled water picks up heat from the magnet water and carries it away.

"It's basically transferring 36 MW of heat from the magnet cooling water loop and transferring that to the chilled water loop," Hunter explained.

The $130,000 instrument is one of several end-of-year upgrades to the chilling system that will also include larger pipes and new water filters. It will help the plant run more efficiently and, as one of two similar units, and help ensure chilled water for the more than 1,700 users who come to perform research on the lab’s world–record magnets each year.

Story by Kristen Coyne. Photo by Stephen Bilenky.

Last modified on 5 October 2017