Study of turbulence in atomizing liquid jets. (August 2020)

• Record Type: Journal Article
• Authors: Torregrosa, Antonio J.; Payri, Raúl; Javier Salvador, F.; Crialesi-Esposito, Marco
• Is Part Of: International journal of multiphase flow. Volume 129(2020)
• Publication Date: 2020-08
• Subjects: Energy spectra -- Pseudo-fluid -- Turbulence -- Primary atomization -- Kolmogorov scale; Multiphase flow -- Periodicals; Écoulement polyphasique -- Périodiques; Multiphase flow; Periodicals; 620.1064
• DOI: 10.1016/j.ijmultiphaseflow.2020.103328
• Languages: English
• ISSNs: 0301-9322

Abstract

Highlights: Direct Numerical Simulation of an atomizing liquid jet is performed to collect convergent statistics for one-point and two-point quantities with high space-time resolution. Energy dissipation rate is computed, allowing an accurate computation of the Kolmogorov scale in a multiphase flow by using a pseudo-fluid approach. Smooth one-dimensional Kolmogorov scaled spectra shows good agreement with the first similarity hypothesis and −5/3 law. Abstract: Among the many unknowns in the study of atomizing sprays, defining an unambiguous way to analyze turbulence is, perhaps, one of the most limiting ones. The lack of proper tools for the analysis of the turbulence field (e.g. specific one/two-point statistics, spectrum, structure functions) limits the understanding of the overall phenomenon occurring, impeding the correct estimation of motion scales (from the Kolmogorov one to the integral one). The present work proposes a methodology to analyze the turbulence in atomizing jets using a pseudo-fluid method. The many challenges presented in these types of flows (such as temporal fluid properties uncertainties, strong anisotropy and lack of a priori chance of determining the motion scales) can be simplified by such a method, as it will be clearly shown by the smooth results obtained. Finally, the method is tested against the one-phase flows turbulent data available in the literature for the Kolmogorov scaling of the one-dimension energy spectra, showing how a pseudo-fluid method could provide a reliable tool to analyze multiphase turbulence, especially in spray's primary atomization.