Performance Analysis of Novel Propellant Oxidizers using Molecular Modelling and Nozzle Flow Simulations

TL;DR

This study introduces novel carbon-based heterocyclic oxidizers for propulsion, using molecular modeling and nozzle flow simulations to evaluate their performance, showing significant improvements over traditional oxidizers like ammonium perchlorate.

Contribution

The paper presents new potential oxidizer compounds and combines molecular modeling with flow simulations to assess their propulsion efficiency, providing a comprehensive evaluation method.

Findings

Proposed oxidizers have 88-91% of ideal specific impulse.

New oxidizers outperform ammonium perchlorate in propulsion performance.

Supersonic flow simulations yield realistic specific impulse estimates.

Abstract

The primary target of this paper is to present novel compounds in view of their possible use as oxidizers in propulsion applications using molecular modeling calculations and supersonic flow simulations. Carbon-based heterocyclic compounds tend to have strained molecular structures leading to high heats of formation and energetic behavior. In the present work, molecular modeling calculations for molecules of 37 such potential propellant oxidizers are presented. Density functional theory (B3LYP) was employed for the geometry optimization of the proposed molecular structures using the 6-311++G(d,p) basis set. Heats of formation of the compounds were calculated using the molecular modeling results. Appropriate propellant compositions were considered with the proposed compounds as oxidizer components and Ideal specific impulse (Ivac,ideal*) was calculated for each composition assuming isentropic flow, computed using the NASA CEA software package. To predict the actual delivered specific impulse (Ivac,act*), supersonic nozzle flow simulations of equilibrium product gases of each propellant composition have been carried out using OpenFOAM. The standard k-epsilon turbulence model for compressible flows including rapid distortion theory (RDT) based compression term, has been employed. As the problem is inherently transient in nature, local time stepping (LTS) methodology has been further implemented to reach a steady-state solution. These simulations accounted for divergence losses, turbulence losses and boundary layer losses and gave a more realistic estimation of the specific impulse. It was observed that the Ivac,act* for all propellant compositions lie between 88% to 91% of the corresponding ideal value. The newly proposed oxidizers showed considerable improvement in propulsion performance as compared to ammonium perchlorate.