SUMMARY

The main topic of this thesis is to evaluate the use of Abel inversion methods to reconstruct the planar fuel concentration field of a diesel spray using line-of-sight diffuse back-illumination imaging. The Abel transform enables reconstruction of planar data from line-of-sight imaging with just one viewing angle, which is a common limitation for imaging diagnostics applied to experiments under high-pressure and temperature environments. The technique enables cross-validation of data taken from both planar and line-of-sight imaging techniques. This thesis evaluates the sensitivities of the Abel inversion to noise, turbulent fluctuations and asymmetries in data sets and defines a methodology for accurate reconstruction of the planar field. The methodology developed is applied to validate the accuracy of a new optical diagnostic for fuel concentration measurements in a diesel spray known as Ultraviolet-Visible Diffuse Back-Illumination (UV-DBI) imaging. Ultimately, planar fields of fuel concentration are reconstructed from the UV-DBI measurements and are quantitatively validated against existing planar Rayleigh measurements of fuel concentration at matching experimental conditions.