Pressure Control of Variable Air Volume System Based on Infiltration Rate

This study proposes an operational strategy to reduce building infiltration rates by predicting the infiltration rate in a variable air volume (VAV) system and implementing pressure control based on these predictions. To achieve this, a theoretical review of conventional VAV systems operations and its impact on building pressure differences was conducted. A method for predicting infiltration rate based on airflow variations in the VAV system was proposed and validated. Furthermore, a pressure control algorithm that utilizes the predicted infiltration rate was developed and evaluated. Previous studies were limited in capturing real-time envelope pressure differentials and changes in infiltration rate. However, this study predicted infiltration rate based on the exponential relationship between the difference in supply and return airflow rates and pressure differential, and verified its reliability against measured values. Furthermore, pressure control based on predicted infiltration rate reduced the infiltration rate by up to 46.1% compared with fan tracking and volumetric tracking control systems, while also reducing fan energy consumption by 94.7%, confirming its effectiveness in reducing cooling load.