Thermochemical Analysis of Hypergolic Propellants Based on Triethylaluminum/Nitrous Oxide

Stephen M Davis,Nadir Yilmaz

doi:10.1155/2014/269836

Abstract

The vacuum specific impulse, density vacuum specific impulse, and solid exhaust products were examined for several propellant formulations based on the pyrophoric material triethylaluminum (TEA) using CEA thermodynamics code. Evaluation of TEA neat and mixed with hydrocarbon fuels with LOX, N2O, N2O4, liquefied air, and HNO3were performed at stoichiometry. The vacuum specific impulse of neat TEA with N2O is comparable to that of nitric acid with the same, but the N2O formulation will produce slightly less solid products during combustion. Additionally, N2O-TEA propellants have vacuum specific impulses and density vacuum specific impulses within 92.9% and 86.7% of traditional hydrazine propellant formulations under stoichiometric conditions.

Highlights

Nitrous oxide is a commonly used propellant in various applications ranging from aerosol cans to racing vehicles and novel rocket propellants
A thermochemical evaluation of TEA mixed with hydrocarbon solvents hexane, methanol, aniline, nitromethane, and nitropropane was performed with the oxidizers liquid oxygen (LOX), nitrogen tetroxide (NTO, N2 O4 ), nitrous oxide (N2 O), liquefied air, and nitric acid (HNO3 ) using the NASA Lewis Code Chemical Equilibrium with Applications (CEA2) [14]
A thermodynamic analysis of potential hypergolic propellants based on TEA and nitrous oxide was performed and compared to traditional oxidizers

Summary

Introduction

Nitrous oxide is a commonly used propellant in various applications ranging from aerosol cans to racing vehicles and novel rocket propellants. [7]), where hydrogen peroxide is known to ignite hypergolically with pyrophoric materials such as silane and triethylaluminum (TEA) [8, 9]. Pyrophoric materials such as TEA appear to be ideal first-pass candidates for nitrous oxide hypergolic fuels. The case for these chemicals is further strengthened by the use of TEA and SiH4 as supersonic combustion aids, since supersonic combustion requires highly flammable fuels [9]. TEA reduces the ignition delay of hydrazine with nitrogen tetroxide [9] and ignites with air at temperatures as low as −40∘ C [10]

Methods

Results

Conclusion