Journal Article

Characterization of an Ignition System for Nitromethane-Based Monopropellants

Kurilov, Maxim, Kirchberger, Christoph U., Schlechtriem, Stefan

2024

Overview

This paper presents the results of a hot-fire test campaign aimed at characterizing a newly developed ignition system for nitromethane-based green monopropellants. Nitromethane-based propellants are a cost-effective replacement for hydrazine and energetic ionic liquid hydrazine alternatives such as LMP-103S and ASCENT. The developed system uses a glow plug as the ignition source. Additionally, gaseous oxygen is injected simultaneously into the combustion chamber at the beginning of a firing. After closing the oxygen valve, a pure monopropellant operation follows. Three test series were carried out using NMP-001, a previously characterized nitromethane-based monopropellant. During the first test series, the required ROF for ignition was identified to be above 0.3. In the second test series, the low-pressure combustion limit was shown to be 13.9 bar, which is significantly lower than the 30 bar limit of heritage nitromethane-based monopropellants. In the third test series, the oxygen injection timing was optimized to minimize the required amount of oxygen for successful ignition to 1.5 g per ignition in this test setup. This approach to ignition is more cost effective than the catalytic initiation used for other monopropellants because neither costly precious-metal catalytic materials nor lengthy preheating procedures are required.

• Publisher: MDPI AG
• Subject: Alternative energy sources / Armed forces / Combustion / Combustion chambers / Cost effectiveness / Costs / Decomposition / green propellant / Heating / Hydrazines / Hydrocarbons / Hydrogen peroxide / ignition system / Ignition systems / Ionic liquids / Laboratories / Low pressure / Monopropellants / Nitromethane / Oxygen / R&D / Research & development / Satellites / Temperature / Toxicity / Valves