Validation of the DP Matching on the Spark Tracing Method by the Radiant Trail

Abstract

Dynamic programming matching technique, which is used for the voice recognition, has been adapted to the time line images obtained by the spark tracing method for the high speed air flow. As the high voltage sparks between two electrodes trace the air flow very well, we can measure the two or three-dimensional air velocities, if we can quantify the displacement and the time interval between sparks. With the dynamic programming matching technique, the characteristics of the two consecutive spark lines are nicely corresponded and thus the three-dimensional displacement between sparks are quantified. In order to prove that the segments of the sparks are correctly corresponded, presently the radiant trail of the metal powder which is introduced into the sparks are used. As the radiant trail demonstrates the path line of the flow, it is useful to check the flow direction. Furthermore, the appropriate function for the “distance” of the DP matching is proposed.