A novel spectral analysis algorithm to obtain local scalar field statistics from line-of-sight measurements in turbulent flows

Statistical tomography to obtain local field variables from non-intrusive line-of-sight measurements in turbulent flows has been an intriguing subject for some time. In this study, a novel algorithm is presented to obtain statistical information on the local scalar field in axisymmetric turbulent flows. The algorithm uses line-of-sight transverse deflection angle measurements in only one view direction to greatly simplify the optical configuration. The validity of the algorithm is examined using noise-free synthetically generated scalar data that simulate the concentration field of a turbulent helium jet. Results show that the proposed algorithm provides excellent reconstruction of integral length scale and variance of refractive index difference, which can be related to scalar physical properties such as density, temperature and/or species concentrations. Good reconstruction accuracy and the need for a simple optical configuration make the proposed algorithm a promising method to characterize the scalar field in turbulent flows using path-integrated measurements