Ignition and combustion characteristics of gel TMEDA and liquid WFNA in a hypergolic system

• Hypothesis was formulated for ignition and combustion mechanism of TMEDA and WFNA • Increasing fuel particle fall height reduces the ignition delay time • Ignition delay time and burnout time reduced with fuel fall height increase • Maximum flame temperature reached about 1168°C • Microexplosion was detected in 25% of experiments An experimental study was conducted on the ignition and combustion characteristics of a hypergolic system consisting of tetramethylethylenediamine C 6 H 16 N 2 (fuel), thickened with 5 wt% silicon dioxide SiO 2 , and highly concentrated nitric acid HNO 3 (oxidizer) in a liquid state. In the experiments, gel fuel particles with a diameter of 2.5 mm were dropped from different heights (5, 10, 15 and 20 cm) onto a liquid oxidizer layer with a volume of 2 ml. Using high-speed video recording, the following characteristics were recorded: ignition delay times and burnout times of fuel components; the burnout area of the flammable vapor-gas mixture; the average velocity of fragments during a microexplosion. Flame temperatures were determined using high-speed two-color pyrometry. Also, using the Schlieren method, the characteristics were recorded: area and velocity of vapor propagation. Based on the experimental data obtained, a hypothesis was formulated regarding the ignition and combustion mechanism of hypergolic fuel system components (gel fuel particle and liquid oxidizer layer).