Quantification of transient fuel films under elevated ambient pressure environments

Kay, P. J.; Alonso, Mario; Kay, Peter J.; Bowen, Phil J.; Sapsford, S. M.; Gilchrist, R.

Abstract

Impingement of fuel sprays on solid surfaces is of interest in a wide range of industrial applications including automotive, gas turbines, and process and hazard analysis. Consequently, accurate quantification of fuel films is necessary for model validation. In this study, the transient liquid fuel film formed as a result of spray impingement of a direct injection spray, relevant to practical engine operation, is quantified for the first time. A non-intrusive technique utilizing total internal-reflection-laser-induced fluorescence (TIR-LIF) is utilized to quantify the spatial and temporal distribution of the film thickness. The LIF technique is based on the principle that the intensity of the fluorescent signal from a fluorescent tracer is proportional to the film thickness. Application of the technique to elevated pressure conditions is far from trivial since the fluorescence from the dopant can be adversely affected. This technique utilizes TIR to control the propagation of a laser source in order to target the liquid fuel film only and not the airborne droplets, which had been shown previously to induce significant error. A binary mixture of 10% 3-pentanone in iso-octane is used as a substitute for gasoline, and a new linear calibration function is derived for the elevated pressure considered. Observations of the transient development of the liquid fuel films include details of fine surface waves. Significant quantitative differences are found between the TIR-LIF results at 0.1 and 0.4 MPa ambient pressures, and the results are compared and discussed in relation to pre-impingement spray characteristics. © 2012 by Begell House, Inc.

• Journal Article Type: Article
• Publication Date: Jul 25, 2012
• Journal: Atomization and Sprays
• Print ISSN: 1044-5110
• Electronic ISSN: 1936-2684
• Publisher: Begell House
• Peer Reviewed: Peer Reviewed
• Volume: 22
• Issue: 1
• Pages: 79-95
• DOI: https://doi.org/10.1615/AtomizSpr.2012004865
• Keywords: laser-induced fluorescence, fuel films, GDI, gasoline, spray
• Public URL: https://uwe-repository.worktribe.com/output/951284
• Publisher URL: http://dx.doi.org/10.1615/AtomizSpr.2012004865