An experimental study on the hypergolic interaction between monomethylhydrazine and nitric acid

摘要: Abstract The hypergolic interactions between monomethylhydrazine (MMH, CH 3 NHNH 2 ) and various forms of nitric acid were studied by several different experimental techniques. High-speed videos acquired to visualize the pre-ignition, ignition post-ignition events when a fuel drop impinged on pool acid. A three-stage process was identified in temperature profiles obtained from tests using Al O coated fine-wire thermocouples placed both liquid-phase gas-phase regions. rose rapidly ambient levels boiling point first stage, 280 °C relatively slowly second stage flame very third stage. gaseous species evolved reactions MMH these three stages probed confined-interaction setup, conjunction with rapid-scan Fourier transform infrared (FTIR) spectroscopy time-of-flight mass spectrometry (ToFMS). involved which formed ionic compound monomethylhydrazinium nitrate (MMH·HNO ), as well oxidation products methyl (CH ONO azide N O, H . formation an aerosol cloud mainly composed nitrate. rapid leading ignition. These third-stage initiated thermal decomposition acid, this include HONO, , ONO, OH, NH 4 NO, small amounts HNCO, HCN CO Some important pre-ignition are proposed for liquid gas phases.