Correction of beam steering effects in 2d-laser-diagnostic measurements in combustion engines by image postprocessing
In: EUROTHERM Seminar 2002, Visualisation, Imaging and Data Analysis in Convective Heat and Mass Transfer
Reims, France (2002), S. 301-306
Buchaufsatz / Kapitel / Fach: Maschinenbau
Laser-diagnostic imaging is a powerful tool for the investigation of combustion processes in practical applications. It often suffers from beam steering effects induced by temperature and gas density gradients at windows and flame structures. We present an approach to correct beam steering by digital image analysis. In this method signal distortion caused by laser light inhomogeneities is corrected for by local adaptation factors while maintaining averaged signal intensities and thus calibration factors. Experimental data from laser diagnostic measurements at a Diesel spray under engine-like conditions served as a representative test case for our method.