Water Spray Flow Characteristics Under Synthetic Jet Driven By a Piezoelectric Actuator

23rd AIVELA (the Italian Association of Laser Velocimetry and non invasive diagnostics) Annual Meeting 2015

Marchitto, L.^1 ; Valentino, G.^1 ; Chiatto, M.^2 ; De Luca, L.^2

Istituto Motori, CNR, Napoli, Italy^1

Dept. of Industrial Engineering, University of Naples Federico II, Napoli, Italy^2

关键词: Atmospheric conditions;    Droplets sizes;    Injection pressures;    Particle image velocimetries;    Phase Doppler anemometry;    PIV measurements;    Spray parameters;    Synthetic jets;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/778/1/012005/pdf
DOI  :  10.1088/1742-6596/778/1/012005

来源: IOP

【 摘 要 】

Particle Image Velocimetry (PIV) and Phase Doppler Anemometry (PDA) have been applied to investigate the droplets size and velocity distribution of a water spray, under the control of a piezo-element driven synthetic jet (SJ). Tests were carried out under atmospheric conditions within a chamber test rig equipped with optical accesses at two injection pressures, namely 5 and 10 MPa, exploring the variation of the main spray parameters caused by the synthetic jet perturbations. The SJ orifice has been placed at 45° with respect to the water spray axis; the nozzle body has been moved on its own axis and three different nozzle quotes were tested. PIV measurements have been averaged on 300 trials whereas about 105samples have been acquired for the PDA tests. For each operative condition, the influence region of the SJ device on the spray has been computed through a T-Test algorithm. The synthetic jet locally interacts with the spray, energizing the region downstream the impact. The effect of the actuator decreases at higher injection pressures and moving the impact region upwards. Droplets coalescence can be detected along the synthetic jet axis, while no significant variations are observed along a direction orthogonal to it.