Experimental Determination of Ignition Delay for Hypergolic Bipropellants

摘要

An experimental investigation of hypergolicity and ignition delays of hydrazine, unsymmetrical dimethyl hydrazine (UDMH), tetramethylethylenediamine (TMEDA), furfuryl alcohol, triethylamine (TEA), and 2,6-xylidine with white fuming nitric acid (WFNA) and red fuming nitric acid (RFNA) is presented. Results of ignition delays measured using drop test coupled with a high-speed camera and optoelectronic circuit are shown. Physical and chemical ignition delays of all fuels with RFNA are shown. All the fuels were found to be hypergolic in nature with WFNA and RFNA except for furfuryl alcohol, which displayed hypergolicity only with WFNA. Global ignition delays of all the fuels except for TEA were found to be less with RFNA as compared to WFNA. All the fuels showed global ignition delays less than 50 ms, which is the upper limit to classify the hypergols as useful. Amongst the compounds tested, TMEDA shows the lowest ignition delay with WFNA and RFNA and is seen as the best candidate to replace hydrazine based hypergolic compounds.