Experimental and Numerical Simulation to Design an Optimum Impinging Jet Ventilation System

Abstract

The Impinging Jet Ventilation (IJV) system has demonstrated significant potential in improving indoor air quality (IAQ) and supporting thermal stratification. This study proposes a simple and practical method for designing an IJV system optimized for contaminant removal. Experimental and numerical investigations were conducted to compare the performance of the IJV system with that of a conventional overhead (COH) system. The experiments were performed in a controlled test room and used to validate the numerical model, which was then applied to evaluate airflow, thermal distribution, and particle removal efficiency under various operating conditions. Two particle distribution scenarios were examined: particles emitted from a source and particles randomly dispersed in the space. Both systems were tested under identical airflow and heat load conditions. Results showed that the IJV system outperformed the COH system in terms of suspended particle removal and stratified cooling delivery within the occupied zone. The optimal IJV configuration for the examined setup was consistently achieved when the ratio of inlet velocity to inlet height was approximately 6.65 s⁻¹. This finding provides a practical and scalable design guideline, and as a foundation to examine a wider range of setups and configurations in order to establish more generalizable optimal ratios and achieve high-performance ventilation using IJV systems.

Keywords: IJV, IAQ, Displacement Ventilation, Thermal comfort