Simple improvements for decentralized air handling unit for regenerative heat recovery

Abstract

This paper presents the optimization of a fixed regenerative heat exchanger for a decentralized air handling unit (AHU) and a simple algorithm for its control. The influence of the geometric characteristics of the regenerative matrix and the duration of the airflow switching periods on thermal efficiency was analyzed. For this purpose, a numerical analysis using the finite volume method of the ANSYS, Fluent software was used. The simple logic of control is proposed as a result of field experiments and numerical analysis based on close-to-real operating conditions. The control algorithm prevents the operation of the device in case of a significant imbalance of the air flows and in case of a strong deterioration of the efficiency of the regenerator as a result of the presence of condensation of water vapour in the airflow through the regenerator.