Method for planar measurement of temperature in compressible flow using two-line laser-induced iodine fluorescence.
A method for planar measurement of temperature in a compressible flow by means of two-line laser-induced iodine fluorescence is proposed. Temperature is determined from the ratio of the intensities of fluorescence, which are obtained by irradiation of two laser beams of different wavelength. Use of a high-sensitivity vidicon camera permits multiple-point measurements of temperature in the flow field. This method is applied to a supersonic free jet. It is found that the results obtained by P(16)/R(18) (514.720 nm) and P(26)/R(28) (514.942 nm) absorption lines in the transition of B(3)II(ou)+ (nu' = 43) ? X(1)sigma(g)+ (nu'' = 0) can predict temperature below 300 K with an accuracy of +/-5K.