KIT | KIT-Bibliothek | Impressum | Datenschutz

Air-Assisted Atomization at Constant Mass and Momentum Flow Rate: Investigation into the Ambient Pressure Influence With the Smoothed Particle Hydrodynamics Method

Chaussonnet, Geoffroy; Joshi, Shreyas; Wachter, Simon; Koch, Rainer; Jakobs, Tobias; Kolb, Thomas; Bauer, Hans-Jörg

Abstract:
A twin-fluid atomizer configuration is simulated by means of the two-dimensional (2D) weakly compressible smoothed particle hydrodynamics (SPH) method and compared to experiments. The gas-to-liquid ratio (GLR), the momentum flux ratio, and the velocity ratio are set constant for different ambient pressures, which lead to different gaseous flow sections. The objectives of this study are (i) to investigate the effect of ambient pressure at constant global parameters and (ii) to verify the capability of 2D SPH to qualitatively predict the proper disintegration mechanism and to recover the correct evolution of the spray characteristics. The setup consists of an axial liquid jet of water fragmented by a coflowing high-speed air stream (Ug = 80 m/s) in a pressurized atmosphere up to 16 bar. The results are compared to the experiment and presented in terms of (i) mean velocity profiles, (ii) drop size distributions, and (iii) Sauter mean diameter (SMD) of the spray. It is found that there exists an optimal pressure to minimize the mean size of the spray droplets. Finally, two new quantities related to atomization are presented: (i) the breakup activity that quantifies the number of breakup events per time and volume unit and (ii) the fragmentation spectrum of the whole breakup chain, which characterize the cascade phenomenon in terms of probability. ... mehr



Zugehörige Institution(en) am KIT Institut für Thermische Strömungsmaschinen (ITS)
Institut für Technische Chemie (ITC)
Publikationstyp Zeitschriftenaufsatz
Publikationsmonat/-jahr 03.2020
Sprache Englisch
Identifikator ISSN: 0742-4795, 1528-8919
KITopen-ID: 1000117524
HGF-Programm 34.14.02 (POF III, LK 01)
Vergasung
Erschienen in Journal of engineering for gas turbines and power
Band 142
Heft 3
Seiten 031019
Bemerkung zur Veröffentlichung Paper No.: GTP-19-1388
Vorab online veröffentlicht am 04.02.2020
Nachgewiesen in Web of Science
KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft
KITopen Landing Page