No abstract

No abstract

for copying beyond that permitted by Sections 107or 108 of the U.S. Copyright Law. This consent does not extend to other kinds of copying such as copying for general distribution, for advertising or promotional purposes, for creating new collective works, or for resale. SAE routinely stocks printed papers for a period of three years following date of publication. Direct your orders to SAE Customer Service Department. To obtain quantity reprint rates, permission to reprint a technical paper or permission to use copyrighted SAE publications in other works, contact the SAE Publications Group. AN MSAE pper aft. abstracted &nd ndexed in ______ "_ _ the SAE Gjob AAMowry Database. "R GLOM. MOILr'Y OATA3ASE No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher.

An optical patternator can measure the fuel mass distribution of a spray using laser induced fluorescence (LIF) images obtained from a planar imaging technique. In the dense spray region, however, attenuation by scattering from particles in the path of the detector is so significant that the true spray pattern might be altered into a false distribution. Therefore, the method to find the geometric mean value of the intensities obtained from two cameras was evaluated and verified in a solid-cone spray under the assumption that the optical depth is constant throughout the spray. The variation of the averaged optical depth detected by the two cameras was negligible in the present study, so that the deviation of signal attenuation was within ±5% of the average value. The measurement of the mass distribution at Z = 25 mm using a single camera was estimated to have a large range of signal attenuation from 0 to 17%, while the method using two cameras has a small range of signal attenuation from 6.5% to 12.5%. Therefore, the effect of signal attenuation can be dealt with by the two-camera method. This method was also applied to measure the size distribution by taking the ratio of fluorescence to Mie-scattering signals. It was found that Mie-scattering and LIF signals were attenuated at a similar rate within the range of the signal wavelength used in this measurement. Hence, the effect of signal attenuation on the size measurement was cancelled in the single image detection and agreed well with other techniques, such as PDPA.

No abstract