气相PIV中的耀斑消除:荧光示踪粒子的优化
Fluorescent tracer particles have found a number of uses inPIV. A light sheet produces flare when it impinges upon anobject within the field of view, preventing particle imagesfrom being obtained and hence preventing velocitymeasurements in that locality. An example is shown infigure 1 where 532nm light is used for excitation and imaging.Whilst in some situations flare may be minimized by carefulexperiment setup, in some applications flare is difficult toavoid and prevents information from being obtained, e.g. inboundary layer measurements. A further application hasbeen explored where fluorescent tracers are used to opticallylabel one phase or constituent of a flow and thereby enablesimultaneous multi-constituent PIV [1-3].The general application of fluorescent tracers to gas phaseflow seeding requires sufficient fluorescence emission frommicron sized tracers when imaged over 10’s of mm field ofview. For multi-constituent and multi-phase flows sufficientchromatic separation is also required between theillumination and the fluorescence and between thefluorescence and any wavelengths used for Mie scattering.