Date of Award
Master of Science (MS)
Gregor P. Henze
Michael J. Brandemuehl
Low Delta T Syndrome increases the energy consumption of chilled water systems. Numerous causes of Low Delta T lie at the cooling coils. As higher loads are put on a coil, more chilled water is sent through it. A point of saturation is reached when significant increases in chilled water flow results in negligible increases in provided cooling power. Recognition of when such saturation is occurring, and the ability to restrict flow in such situations, is needed to combat Low Delta T. An intelligent, pressure independent control valve attempts this. Through non-linear regression of measured coil data, a new approach for the valve to predict saturation was developed and tested. The resulting curve fit was also used to predict whether a coil was operating in a Constant Air Volume or Variable Air Volume system. 132 test coils over four climates and various system characteristics showed a 79.7% correct identification rate.
Ryan, Miles, "Optimal Control Strategy Selection for Intelligent Pressure Independent Control Valves" (2014). Architectural Engineering Graduate Theses & Dissertations. 2.