elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Large Eddy Simulation of Flashing Cryogenic Liquid with a Compressible Volume of Fluid Solver

Gärtner, Jan W. and Rees, Andreas and Kronenburg, Andreas and Sender, Joachim and Oschwald, Michael and Loureiro, Daniel (2019) Large Eddy Simulation of Flashing Cryogenic Liquid with a Compressible Volume of Fluid Solver. In: 29th European Conference Liquid Atomization and Spray Systems ILASS-Europe 2019. ILASS-Europe 2019, 29th Conference on Liquid Atomization and Sprays Systems, 2. - 4. Sept. 2019, Paris, France.

[img] PDF
1MB

Official URL: https://ilass19.sciencesconf.org/browse/author?authorid=677422

Abstract

For the development of new upper orbit thrusters with cryogenic propellants, it is important to understand the dynamics of oxidizer and fuel injection at near vacuum conditions before ignition. Due to the low ambient pressure with respect to the saturation pressure at the injection temperature, the propellants enter a superheated state and evaporate rapidly. This process is called flash evaporation. To simulate such a flashing cryogenic jet a compressible multiphase solver is developed in OpenFOAM. The homogeneous relaxation model (HRM) is chosen to model the phase change. For solving this multiphase problem, a one-fluid approach which solves for the mixture properties and phase fraction is selected. For the equation of state, the open source library CoolProp is used to calculate density, enthalpy and the saturation conditions. Further, the numerical methods to solve and capture the supersonic multiphase flow with a Volume of Fluid (VoF) method is described. The transition from mechanical break up to fully flashing spray and the change from subsonic to supersonic flow is investigated in detail. The numerical results are validated with experiments conducted at DLR Lampoldshausen which provide shadowgraph images. As a first approximation to fuel-oxidizer mixing, cryogenic nitrogen jet experiments at the DLR test bench M3.3 in Lampoldshausen are made and numerically investigated with large eddy simulations. It is noted that the flashing jet becomes supersonic and forms a shock shortly after the nozzle exit. This occurs despite the velocity being lower than the sonic velocities associated with each individual pure phase. The results show that the HRM model can predict the onset of the partial flashing flow, however fully flashing jet with 180 degree spray angle cannot be predicted with standard coefficients of the HRM model.

Item URL in elib:https://elib.dlr.de/132833/
Document Type:Conference or Workshop Item (Speech)
Title:Large Eddy Simulation of Flashing Cryogenic Liquid with a Compressible Volume of Fluid Solver
Authors:
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Gärtner, Jan W.Universität Stuttgart, Institut für Technische Verbrennung, Stuttgart, DUNSPECIFIED
Rees, AndreasAndreas.Rees (at) dlr.dehttps://orcid.org/0000-0002-4114-636X
Kronenburg, AndreasUniversität Stuttgart, Institut für Technische Verbrennung, Stuttgart, DUNSPECIFIED
Sender, JoachimJoachim.Sender (at) dlr.dehttps://orcid.org/0000-0002-7408-1208
Oschwald, MichaelMichael.Oschwald (at) dlr.dehttps://orcid.org/0000-0002-9579-9825
Loureiro, DanielUniversität Stuttgart, Institut für Technische Verbrennung, Stuttgart, DUNSPECIFIED
Date:2019
Journal or Publication Title:29th European Conference Liquid Atomization and Spray Systems ILASS-Europe 2019
Refereed publication:Yes
Open Access:Yes
Gold Open Access:No
In SCOPUS:No
In ISI Web of Science:No
Status:Published
Keywords:flash-boiling, homogeneous relaxation model (HRM), compressible multiphase solver, flashing cryogenic nitrogen
Event Title:ILASS-Europe 2019, 29th Conference on Liquid Atomization and Sprays Systems
Event Location:Paris, France
Event Type:international Conference
Event Dates:2. - 4. Sept. 2019
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Space
HGF - Program Themes:Space Transport
DLR - Research area:Raumfahrt
DLR - Program:R RP - Raumtransport
DLR - Research theme (Project):R - Leitprojekt - Forschungsverbund Oberstufe
Location: Lampoldshausen
Institutes and Institutions:Institute of Space Propulsion > Rocket Propulsion
Deposited By: Hanke, Michaela
Deposited On:16 Dec 2019 17:15
Last Modified:16 Dec 2019 17:15

Repository Staff Only: item control page

Browse
Search
Help & Contact
Information
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.