Patent · US Active

Demand flow pumping

US8275483B2 · kind B2 · utility

15Cited by
30References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 23, 2009
Grant dateSep 25, 2012
Priority date
Expiry dateJul 7, 2030

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF24F2110/00
  • WIPO fieldThermal processes and apparatus
  • WIPO sectorMechanical engineering

Abstract

Demand Flow operates chilled water plants at substantially improved efficiency, regardless of plant load conditions. In general, Demand Flow utilizes an operating strategy which controls chilled and condenser water pumping according to a constant Delta T line, which is typically near or at design Delta T. This reduces or eliminates Low Delta T Syndrome and reduces energy usage by chilled and condenser water pumps for given load conditions. Operation of chilled water pumps in this manner creates a synergy which generally balances flow rates throughout the plant, reducing undesirable bypass mixing and energy usage at air handler fans and other components of the chilled water plant. At plant chillers, application of Demand Flow increases the refrigeration effect through refrigerant sub-cooling and superheating, while preventing stacking. Demand Flow includes a critical zone reset feature which allows the constant Delta T line to be reset to adjust to changing load conditions.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.