publications - Thermofluid Dynamics

Journal publications / Peer-reviewed publications (since 2009)

2020

R. Groll, S. Kunze, B. Besser : Correction of Second-Order Slip Condition for higher Knudsen Numbers by Approximation of Free-Molecular Diffusion, Phys. Fluids 32, 092008; doi.org/10.1063/5.0021711 , AiP 2020

M. v. Einem, C. Heinicke, R. Groll : Numerical analysis of the ventilation in a moon habitat laboratory module, IAC20.B3.4-B6.4.10, iafastro.directory/iac/paper/id/56462/summary/, 71st International Astronautical Congress, IAF 2020

2019

R. Groll : Dynamic selection limiter schemes for high density gradient simulationsof supersonic rarefied gas flows, PAMM 19(1), doi.org/10.1002/pamm.201900199 , Wiley 2019

2018

C. Chelem-Mayigue, C. Kühn, R. Groll : Performance investigation of an Argon fueled magneto-plasma dynamic thruster with applied magnetic fields, doi.org/10.1063/1.5038421 , Journal of Applied Physics, 124:223301 AIP 2018

C. Chelem-Mayigue, R. Groll : Numerical simulation of Argon fuelled self-field magneto-plasma dynamic thrusters using the central-upwind schemes fluxes interpolation, doi.org/10.1016/j.euromechflu.2018.07.010, European Journal of Mechanics B/Fluids 72:645-663, Elsevier 2018

T. Frieler, R. Groll : A torsional sub-millinewton thrust balance based on on a spring leaf strain gauge sensor, doi.org/10.1063/1.4996419 , Review on Scientific Instruments 89:075101 , AIP 2018

P. Liang, R. Groll : Numerical study of plasma-electrode interaction during arc discharge in a DC Plasma Torch, ieeexplore.ieee.org/document/8249741 , IEEE Transaction in Plasma Science 46(2):363-372, IEEExplore 2018

R. Groll, C. Kühn : Shear force analysis of an oil-driven grinding tool, doi.org/10.2495/CMEM-V6-N2-231-239 , Int. Journal on Computational Methods and Engineering Measurements 6(2):231-239, WITpress 2018

2017

C. Chelem-Mayigue, R. Groll : A density-based method with semi-discrete central-upwind schemes for ideal magnetohydrodynamics, Archive of Applied Mechanics 87:667-683, doi:10.1007/s00419-016-1216-7, Springer 2017

E. Brinksmeier, B. Orlik, R. Groll, C. Flosky, A. Norbach, K. Leach, J. Gomez : GrindBall - Novel Drive and Bearing Concept for Micro Grinding Tools, Chapter in: Small Machine Tools for Small Workpieces (Eds. J. P. Wulfsberg, A. Sanders), doi:10.1007/978-3-319-49269-8_5, ISBN: 978-3-319-49267-4, p. 65-85, Springer 2017

2016

R. Groll, J. E. Gomez : Identifying microproduction inaccuracies with Knudsen number depending correction functions, AiP Conf. Proc. 1786:080012, doi:10.1063/1.4967605, AiP 2016

C. Chelem-Mayigue, R. Groll : Magneto-plasmadynamic thruster modelling with coaxial induced magnetic field, Int. Journal on Computational Methods and Engineering Measurements 4:4, p. 380-392, doi: 10.2495/CMEM-V4-N4-380-392, WITpress 2016

J. E. Gomez, R. Groll : Experimental and numerical study of the pressure drop in transonic micronozzle flows across multiple flow regimes, ASME Digital collection, doi:10.1115/ICNMM2016-7919, American Society of Mechanical Engineers, ASME 2016

R. Groll, J.E. Gomez : Calibrating microfluidic pressure correction functions in Laval nozzle flow by eliminating production accuracy influences, PAMM 16(1):581-582, doi:10.1002/pamm.201610279, Wiley 2016

C. Chelem-Mayigue, R. Groll : Computational magneto-hydrodynamic modeling of hypersonic flows with resolved shock wave diffusion, PAMM 16(1):621-622, doi:10.1002/pamm.201610299, Wiley 2016

J. E. Gomez, R. Groll : Pressure drop and thrust predictions for transonic micronozzle flows, Physics of Fluids 28(2):022008,  doi:10.1063/1.4942238, AiP 2016

2015

T. Brandt, T. Trottenberg, R. Groll, F. Jansen, F. Hey, U. Johann, H. Kersten, C. Braxmaier : Simulation for an improvement of a down-scaled HEMP-Thruster, e-publication: Electronic Rocket Propulsion Society, IEPC-2015-90172, ERPS 2015

C. Zimmermann, R.Groll : Computational investigation of thermal boundary layers in a turbulent Rayleigh-Benard problem, Int. Journal of Heat an Fluid Flow 54:276-291, Elsevier 2015

T. Brandt, T. Trottenberg, R. Groll, F. Jansen,
F. Hey, U. Johann, H. Kersten, C. Braxmaier : Simulations on the influence of the spatial distribution of source electrons on the plasma in a cusped-field thruster, Eur. Phys. Journal D 69:145, Springer 2015 

R. Groll, J. E. Gomez : Computational multi-component modelling of electron transport and ohmic heating inside a micro arc-jet thruster, Transactions on Engineering Sciences 89, p.3-16, ISBN 978-1-84564-946-3, WIT Press 2015

R. Groll : Micro diffuser flow modeling for cold gas propulsion systems, PAMM 14(1):633–640, Wiley 2014

C. Zimmermann, R.Groll : Experimental and numerical and experimental investigation of a Reyleigh-Benard convection affected by Coriolis force, Journal of Flow Control, Measurement and Visualization 2:165-172, ISSN 2329-3322 Scientific Research 2014

C. Zimmermann, R. Groll : Modelling turbulent heat transfer in a natural convection flow, Journal of Applied Mathematics and Physics, ISSN 2327-4352, 2(7):662-670, Scientific Research 2014

R. Groll: Transonic wall-slip analysis for expanding micro diffuser flows for cold gas propulsion systems, ASME electronic publication, Order No. ASME-46278:V001T01A005, doi:10.1115/ICNMM2014-21822, ASME 2014

R. Groll, J. E. Gomez: Investigating and modeling the correlation of pressurization and electron acceleration inside a micro arc-jet thruster, ASME electronic publication, Order No. ASME-46278: V001T06A002, doi:10.1115/ICNMM2014-21214, ASME2014

T. Brandt, T. Trottenberg, R. Groll, F. Jansen, F. Hey, U. Johann, H. Kersten, C. Braxmaier: Simulation of a down-scaled HEMP-Thruster, 5th German-Russian Conference on Electric Propulsion, Dresden, Germany 2014

T. Brandt, R. Groll, F. Jansen, U. Johann, A. Keller, H. Kersten, C. Braxmaier : Particle-in-Cell simulation of the plasma properties and ion acceleration of a down-scaled HEMP-Thruster, 19th International Spacecraft Propulsion Conference, Cologne, Germany 2014

R. Groll : Modelling plasma flow with particle classes for different charge carriers and neutral particles, Transactions on Engineering Sciences 79:25-34, p.25-34, ISBN 978-1-84564-734-6, WIT Press 2013

E. Brinksmeier, B. Orlik, R. Groll, C. Brandao, A. Norbach, K. Leach : Grindball-Modul zum achsenlosen Mikroschleifen, ANT Journal 2/2013:14-19, Vereinigte Fachverlage 2013

E. Brinksmeier, B. Orlik, R. Groll, C. Brandao, A. Norbach, K. Leach : Grindball: an advanced micro-grinding tool, Production Engineering 7:5, p.469-476, ISBN 0944-6524, Springer 2013

K. Leach, R. Groll : Modelling Abrasion Forces in a Pneumatically Powered Grinding Tool using Compressible Large Eddy Simulation, Journal of Energy and Power Engineering 7:9, p.1634-1643, ISSN 1934-8975, David Publishing 2013

S. Reichel, R. Groll : Numerical Simulation and experimental validation of a hypersonic flow for numerical modulation of re-entry phenomena prediction using adaptive mesh refinement, Int. Journal of Computational Methods and Experimental Measurements 1:4, p. 381-394, WITpress, 2013.

T. Brandt, R. Groll, F. Jansen, U. Johann, A. Keller, H. Kersten, C. Braxmaier : Magnetohydrodynamics and particle-in-cell codes simulation of plasma processes in micro HEMP thrusters, e-publication: Electronic Rocket Propulsion Society, IEPC-2013-145, ERPS 2013

2012

R. Groll, C. Zimmermann, H. J. Rath : Compressible Large-Eddy Simulation of Boundary-Layer Heat Transfer in a Turbulent Convective Flow, PAMM 12(1), Wiley 2012

S. Reichel, R. Groll H. J. Rath: Unsteady numerical simulation with adaptive mesh refinement of a hypersonic double-cone geometry for re-entry phenomena prediction, Computational Methods in Applied Science and Engineering 6, ISBN: 978-3-9502481-9-7, Wien

K. Leach, R. Groll, H. J. Rath : Large-Eddy Simulation of a Pneumatically Powered Abrading Sphere, Fluid Flow Technologies 15:600-607, ISBN 978-963-08-4586-1, FFT 2012.

C. Zimmermann, R. Groll : Modelling turbulent heat transfer of a Rayleigh-Benard problem with compressible Large-Eddy simulation, Turbulence, Heat and MassTransfer 7:615-622, ISBN 978- 1-56700-301-7, Begell House Inc. 2012

R. Groll, F. Fastabend, H. J. Rath: Modelling Transsonic Flows Through Ring-Shape Thruster Geometries with DSMC, ASME electronic publication, Order No. ASME-44793:195-204, doi:10.1115/ICNMM2012-73027, ASME 2012

2011

R. Groll : Heat and mass transfer in evaporating turbulent Drop-laden flow, Transactions on Engineering Sciences 70:129-140, ISBN 978-1-84564-518-1, WIT Press 2011.

R. Groll, T. Schadowski, S. Reichel, H. J. Rath : Computational modelling of transsonic flow in a thermo-electric propulsion system, DLRK 2011 Proceedings, 1479-1480, DGLR 2011.

S. Reichel, R. Groll, H. J. Rath : Experimental Investigation and Numerical Modeling of Electric Heating Rate in a Generic Electric Propulsion System, e-publication: Electronic Rocket Propulsion Society IEPC-2011-063, ERPS 2011

R. Groll : Velocity and Temperature Boundary-Layer Modeling Using Averaged Molecule cluster Transport Equations, IUVSTA 64 Proceedings (Document, Presentation), IUVSTA 2011

2010

R. Groll, H. J. Rath : On Eulerian modelling of microchannel gas flows closing higher statistical moments of molecule velocity; ASME electronic publication, Order No. ASME-54501:407-412, ISBN 978-0-7918-3880-8, E-Lib ISBN: 978-0-7918-5450-1, doi:10.1115/FEDSM-ICNMM2010- 30212, ASME 2010

R. Groll : Statistical Eulerian diffusion approach of four-way-coupled multiphase systems; Defect and Diffusion Forum 297-301:832-837, doi:10.4028/www.scientific.net/DDF.297-301, Trans Tech Publications Inc. 2010.

R. Groll : On an α-a model describing vaporizing droplet clouds in turbulent flows, SPRAY 2010 Proceedings, 2010.

2009

R. Groll : Thermodynamic consistence of statistical modelling molecular diffusion, energy flux and entropy production; Turbulence, Heat and Mass Transfer 6:81-86, ISBN 978-1-56700-262-1, Begell House Inc. 2009.

R. Groll : Mathematical modelling on particle diffusion in fluidised beds and dense turbulent two-phase flows; Transactions on Engineering Sciences 63: 241-250, ISBN 978-84564-188-7, WIT Press 2009.

R. Groll, H. J. Rath : Thermodynamics / turbulence analogy modelling dissipating molecular gas flows for high Knudsen numbers; PAMM Vol. 8:10595-10596, doi:10.1002/pamm.2008 , 2009.

R. Groll, S.Jakirlic, C. Tropea : Comparative study of Euler/Euler and Euler/Lagrange approaches simulating evaporation in a gas-liquid flow; Numerical Methods in Fluids 59(8):873-906, doi:10.1002/fld.1844, Elsevier 2009.

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