Formulation of jet fan performance in reverse operation for road tunnels.

Abstract

The authors showed that the equation for predicting pressure boost in reverse operation of jet fans(JF). In this paper authors propose the way of deciding control volume appropriate for reverse operation of JF, and applied momentum theory to it. Comparison of the equation with the CFD results, it turned out that a good agreement was obtained in the region under 6m/s of longitudinal air flow, while some discrepancy was observed in higher airflow region. The equation proposed in the paper can be applied for practical use, but improvement is desired so that wider range of airflow velocity is covered.