Temperature measurement of an axisymmetric flame by using a schlieren system

Abstract

We present an expanded article based on the research presented at the RIAO/OPTILAS07 conference. The application presented at the conference has been extended to the measurement of temperature by using a schlieren system of an axisymmetric flame issuing from a circular nozzle of a butane head torch. As the temperature of the flame varies with the air/fuel mixture, two different flow conditions, with full and partial air/fuel mixtures, have been analyzed. In order to find out any differences in the structure of the flame for the two cases, the proper orthogonal decomposition (POD) method is applied. From the flame temperature measurements, we compute the eigenfunctions and the eigenvalues by the POD analysis. Two and one dominant POD modes for the partial and full air/fuel mixture were found, respectively. Also, the essential features of the flame temperature fields can be described by considering only the first ten POD modes.