A chilled water thermal storage system utilizes a series of tanks to store chilled water to supplement chillers in the event of a power failure. Chilled water is diverted from the storage tanks to critical equipment during chiller restarting, bridging the gap in time that the chillers are unable to provide chilled water due to power failure and subsequent restart.
Frequently, conventional engineering tools are not enough to address the design challenges of developing an effective chilled water thermal storage system. Due to this issue, our team at Southland Engineering uses advanced tools such as computational fluid dynamics (CFD) and innovative approaches to design the thermal storage tanks.
As part of the commissioning effort for one of Southland’s recent government projects in the Mid-Atlantic region, we tested the installed thermal storage system at the same conditions that we had originally simulated in the CFD model. The results of the field-testing showed that the thermal storage tanks provided a discharge capacity of approximately 19 minutes, verifying that the CFD model Southland designed was accurate within a two percent margin of error. This outstanding result validates our efforts with CFD modeling to prove the effectiveness of our designs. Using this process also helped the project’s design-build team save time, materials, and building square footage by reducing the number of required storage tanks to provide the required storage quantity.
The animation above illustrates how warm water gets into the tank and pushes out the cold water from the bottom of the tanks with minimal mixing. Overall, CFD is an important tool that helps Southland Engineering innovate during the design phase and potentially save customers time and money on projects during the building phase.