Development of Fibre LDV and Measurements of Turbulence in Boundary Layer on a Flat Plate

Abstract

The grading up of LDV performance inevitably follows the increase of weight of the equipment and it requires fine techniques for setting up optic devices due to its complexity of the structure. For measuring the flow pattern a large traverser will have to be used. However, the probe will be miniaturized by use of fibre optics and will be easily employed in any attitude. This paper deals with the development of a fibre LDV with double Bragg cells to measure backward flows and presents the results measured in the boundary layer on a heating plate in an inclined flow to the gravitational direction.