Prediction of Amine‐Based Liquid Rocket Propellant Shelf Life

Abstract

The storage stability of amine based rocket fuel called Samine was studied over 9 months for the first time. It was found that storage stability significantly depends on fuel oxidation with the air trapped in the storage tanks. A reduction of the triethylamine concentration from 50.2 % (wt) to less than 48 % was taken as the end of shelf life of the propellant. After obtaining experimental data from accelerated storage stability tests, the shelf life of Samine was estimated using the Arrhenius equation. According to the kinetic studies, the oxidation reaction of fuel was a zero order reaction and the shelf lives of Samine in stainless‐steel tanks at 20 °C, 25 °C, and 30 °C were obtained to be 5.7, 3.7, and 2.4 years, respectively. Additionally, it was observed that for long time storage of amine based fuels like Samine it is better to use stainless‐steel or aluminum tanks, which are charged with an inert gas like nitrogen.

Influencing Factors of Autoxidation Kinetics Parameters of Endothermic Hydrocarbon Fuels

“…When T = 293.15 K, k 1 = 3.1224 × 10–10 h –1 and k 2 = 1.7736 × 10–12 h –1 can be obtained from formulas of ln k versus 1/ T (Figure ). The reaction can be regarded as zero-order at 20 °C, , that is, a 1 = a 2 = b 1 = b 2 = 0, and eq is equal to eq . When eq is combined with integrated [O 2 ] and t for eq , the result is expressed by eq . where [O 2 ] 0 is O 2 concentration of untreated fuels at room temperature, ppm; [O 2 ] a is the final concentration of O 2 , ppm; k 1 is the rate constant of eq , h –1 ; k 2 is the rate constant of eq , h –1 ; t is oxidation time, h.…”

“…In recent years, chemical kinetic models have been developed which simulate the major autoxidation pathways that occur in jet fuels. , Calculating kinetics is a common method to investigate reaction rates and activation energy. Moreover, the kinetic equations can be used to predict the storage period of liquid fuels and propellants, such as the Arrhenius and Berthelot equations. − Density functional theory is also used to calculate the energetics and kinetics of important reactions for jet fuel oxidation. , Autoxidation can cause fuel deterioration, − such as dissolved oxygen reacting with fuel to produce peroxy radicals, which in turn form peroxides. Peroxide has a serious corrosion effect on rubber, , which can cause aging and cracking of sealing materials in the aircraft oil system and result in fuel leakage.…”

Storage Lifetime Prediction of Composite Solid Propellant based on Šesták‐Berggren Model

“…Many scholars have done a lot of research work in predicting the storage lifetime of composite solid propellants. The traditional method is to use exponential function, power function or linear function to curve-fit its performance characteristic parameter change rule, and determine the pseudo lifetime point estimate value under each stress level according to the failure threshold of the corresponding performance parameter, and then use the Arrhenius equation, Berthelot equation, Eyring model and other modelling extrapolate storage lifetime under normal stress [1][2][3][4][5]. In view of the shortcomings of this type of model, some scholars have modified the traditional method to improve the accuracy of propellant storage lifetime estimation [6][7][8][9][10][11][12].…”