Sensitivity Analysis of a Two-Phase CFD Simulation of a 1 kN Paraffin-Fueled Hybrid Rocket Motor

Benoit Dequick, Michel Lefebvre and Patrick Hendrick
Additional contact information
Benoit Dequick: Royal Military Academy, Avenue de la Renaissance 30, 1000 Brussels, Belgium
Michel Lefebvre: Royal Military Academy, Avenue de la Renaissance 30, 1000 Brussels, Belgium
Patrick Hendrick: École Polytechnique de Bruxelles, Aero-Thermo-Mechanics Department, Université Libre de Bruxelles, Avenue F.D. Roosevelt 50, 1050 Brussels, Belgium

Energies, 2021, vol. 14, issue 20, 1-35

Abstract: At Université Libre de Bruxelles (ULB), research was performed on a 1 kN lab-scale Hybrid Rocket Motor (the ULB-HRM). It has a single-port solid paraffin fuel grain and uses liquid N 2 O as an oxidizer. The first Computational Fluid Dynamics (CFD) model of the motor was developed in 2020 and improved in 2021, using ANSYS Fluent software. It is a 2D axisymmetric, two-phase steady-state Reynolds-Averaged Navier–Stokes (RANS) model, which uses the average fuel and oxidizer mass flow rates as inputs. It includes oxidizer spray droplets and entrained fuel droplets, therefore adding many additional parameters compared to a single-phase model. It must be investigated how they affect the predicted operating conditions. In this article, a sensitivity analysis is performed to determine the model’s robustness. It is demonstrated that the CFD model performs well within the boundaries of its purpose, with average deviations between predicted and experimental values of about 1 % for the chamber pressure and 5 % for the thrust. From the sensitivity analysis, multiple observations and conclusions are made. An important observation is that oxidizer related parameters have the highest potential impact, introducing deviations of the predicted operating chamber pressure of up to 18%, while this is only about 6 % for fuel-related parameters. In general, the baseline CFD model of the ULB-HRM seems quite insensitive and it does not suffer from an excessive or abnormal sensitivity to any of the major parameters. Furthermore, the predicted operating conditions seem to respond in a logical and coherent way to changing input parameters. The model therefore seems sufficiently reliable to be used for future qualitative and quantitative predictions of the performance of the ULB-HRM.

Keywords: hybrid rocket; paraffin; nitrous oxide; CFD; RANS; simulation; two-phase; sensitivity analysis (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2021
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/14/20/6794/pdf (application/pdf)
https://www.mdpi.com/1996-1073/14/20/6794/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:14:y:2021:i:20:p:6794-:d:658857

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().