This paper discusses issues related to investigation of gas jets collision. In order to identify the structure of the flow data on instant field of temperature, which is characteristic variable is used. The paper presents results of experimental studies of the flow structure at collision of coaxial gas jets. Direct flowing jets and those swirled using axial swirler wer investigated. Various modes of thermal-mechanical interaction have been identified and discussed; the criteria for occurrence of these modes have been determined. It was found that for direct flow jets two primary modes of thermal-mechanical interaction exist with a single monozone formation being a characteristic feature of the first mode, while the second mode is marked by discrete zone of jets collision, which indicates emergence of a system of vortexes. Besides, experiments were run for colliding jets with different swirls and velocities. It was found that with different swirl rate of the colliding jets the discrete interaction zone manifests asymmetry.