Trace-analysis of differential chronoscopy of the SHS combustion wave by high-speed television recording

Authors: Gulyaev P. Yu., Iordan V. I., Mulyarets V. V.

Annotation: The influence of the random structure of the powder mixture of the initial products on the motion of the front of the combustion wave quasiperiodically changes the temperature, velocity, and direction of propagation of the combustion wave in the process of self-propagating high-temperarure synthesis (SHS). The task of analyzing the microheterogeneous combustion structure, which is a «discreteness problem» for SHS, calls for the development of means for analyzing the local instability of the motion of the SHS combustion wave. The solution to this problem is seen in the application of mathematical methods for compressing video data by introducing the interframe difference into the signal processing path and parametrizing the results of differential chronoscopy (DCS) using Fast Fourier transform (FFT), Trace transform (TT) or Hough algorithms. The aim of the paper is to select a characteristic for recognizing the critical modes of propagation of the SHS combustion wave based on the results of applying FFT and TT transformations to DCS maps obtained on the basis of high-speed video data. The paper describes the methodology and technique of the experiment with the use of optoelectronic means for video recording of the propagation of the SHS combustion wave, the peculiarities of applying of Trace transform to DCS maps. Based on the analysis of Trace-images of DCS maps, statistical characteristics are proposed for recognizing the critical combustion regime of SHS. The sensitivity of recognition of the change in the discreteness of the SHS wave is compared by means of the proposed statistical characteristics for different functional "kernels" of the Trace transform of the DCS maps. As a result of this comparison, the most effective of the considered functional "kernels" of the Trace transform was determined, which makes it possible to determine the instable combustion regimes in the SHS technology.

Keywords: high-speed television recording, differential chronoscopy, trace transform, shs combustion wave