Study on electrical ignition and micro-explosion properties of HAN-based monopropellant droplet

Abstract

In order to study the electrical ignition characteristics of hydroxylammonium nitrate (HAN)-based liquid propellant, an experimental device for the electrical heating ignition of a liquid propellant droplet was designed. By using a high speed camera system, the ignition properties of the LP1846 single droplet were observed at different electrical heating speeds. The results show that when the LP1846 droplet is electrified, it mainly goes through an evaporization process, a periodic expansion and contraction process, a stronger thermal decomposition process, and an ignition and combustion process. The periodic expansion and contraction process accompanies the droplet micro-explosion phenomenon, and the micro-explosion mechanism is formed mainly due to the overheated water component in LP1846. When peak load voltage is from 80 to 140V/s, the ignition delay of the LP1846 droplet is linearly shortened from 0.82 to 0.62s, but the flame is lighter. Based on the above experiments, a simplified model of the electrical heating ignition of the LP1846 single droplet is established.

Keywords

liquid propellant / electrical ignition / ignition delay time / transient measurement