Experimental tests have been carried out in order to acquire knowledge about the interaction between jet fans and the resulting secondary flow in tunnels with standard circular A.N.A.S. (Italian Road Board) cross section. During the experiment programme, model jet fans are hug with different distances between jet axes, tunnel roof and pitch angles. The resulting tunnel flow, with develops along the tunnel, is studied using a five hole probe and the effectiveness of the impulse fan is determined. In the test series the velocity distribution at the nozzle exit has been changed and the difference of the swirl has been evaluated. The aerodynamic characteristics of the single and couple jet fans as well as the probable onset of recirculation are reported as a function of the effects of eccentricity and pitch angle.
THE INFLUENCE OF SEPARATION, INCLINATION AND SWIRL ON SINGLE AND COUPLED JET FANS INSTALLATION EFFICIENCY
MARTEGANI, ANTONIO DARIO;PAVESI, GIORGIO;
1997
Abstract
Experimental tests have been carried out in order to acquire knowledge about the interaction between jet fans and the resulting secondary flow in tunnels with standard circular A.N.A.S. (Italian Road Board) cross section. During the experiment programme, model jet fans are hug with different distances between jet axes, tunnel roof and pitch angles. The resulting tunnel flow, with develops along the tunnel, is studied using a five hole probe and the effectiveness of the impulse fan is determined. In the test series the velocity distribution at the nozzle exit has been changed and the difference of the swirl has been evaluated. The aerodynamic characteristics of the single and couple jet fans as well as the probable onset of recirculation are reported as a function of the effects of eccentricity and pitch angle.Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
