Estimating laser transit anemometry noise performance capabilities

A Monte Carlo based LTA (laser transit anemometry) simulation system has been used to perform a detailed devaluation of a set of processing algorithms proposed by W.T. Mayo and A.E. Smart (1984) for the extraction of two-dimensional flow parameters from LTR data sets collected in a plane normal to the optical axis of the system. The present evaluation includes data ensembles containing 0.0, 5.0, 10.0, and 20.0% background noise levels in the constituent correlograms. The results of these evaluations indicate that for turbulence levels of up to 10.0% the processing system is able to extract the necessary flow parameters accurately from the LTA data sets. Mean velocity magnitude and flow angle are measurable to within +2.0% for turbulence intensity levels of up to 14.0% and the background noise levels mentioned. Standard deviations are measurable to within +10.0% over a turbulence range of 3.0% to 10.0% and the same noise levels. The correlation coefficient between the u and ν components of velocity is measurable to within a few percent for coefficients greater than 0.4. However, for values of the correlation coefficient less than 0.4, the accuracy of the measurements is noticeably worse due to the geometrical method used to determine the higher-order moment flow parameters. These results indicate that the algorithms described have applications in fluid flow surveys