Evaluation of concepts and methods for extraction of flow parameters from laser transit anemometry data Available to Purchase

Concepts and associated algorithms for the extraction of two-dimensional flow information from laser transit anemometry (LTA) data have been developed and evaluated through the use of a Monte-Carlo type simulation program. The Monte-Carlo LTA simulation program models a flow field as well as the sample volume geometry of the LTA system, thereby permitting simulation of two-dimensional data acquisition in a three-dimensional flow field. The algorithms extract from measurements made in a plane perpendicular to the optical axis of the LTA system the u and v components of mean velocity and turbulence intensity and the associated correlation coefficient. In general the results of evaluations on the proposed processing concepts indicate an ability of the instrument to measure mean velocities to less than +0.15% error and flow angles to less than +0.3% error for turbulence intensities of up to 15.0%. Higher order statistical moments of σ_u, σ_v, and ρ are measureable to less than +11.0% error for turbulence intensity inputs greater than 3.0%. We present here a discussion of the data extraction algorithms and simulation system, and present the results of tests and evaluations on the algorithms.