2D temperature measurements in the wake of a heated cylinder using LIF

A technique is described to measure the instantaneous 2D temperature distri bution in the wake of a heated cylinder using 'laser-induced fluorescence'. Rhodamine B, a fluorescent dye, is used as a temperature indicator. The re lation between fluorescence intensity and temperature is determined by mean s of calibration experiments in the temperature range of 20-35 degreesC wit h an accuracy of +/-0.1 degreesC. The temperature distribution behind the h eated cylinder is well visible and can be measured with a high spatial reso lution. Corrections for variation in laser energy and intensity distributio n in the laser sheet have to be made to further improve the accuracy of the measuring method.