Kordilla, Jannes

[["dc.bibliographiccitation.firstpage","610"],["dc.bibliographiccitation.journal","Journal of Hydrology"],["dc.bibliographiccitation.lastpage","619"],["dc.bibliographiccitation.volume","576"],["dc.contributor.author","Haselbeck, Valentin"],["dc.contributor.author","Kordilla, Jannes"],["dc.contributor.author","Krause, Florian"],["dc.contributor.author","Sauter, Martin"],["dc.date.accessioned","2020-12-10T14:25:10Z"],["dc.date.available","2020-12-10T14:25:10Z"],["dc.date.issued","2019"],["dc.identifier.doi","10.1016/j.jhydrol.2019.06.053"],["dc.identifier.issn","0022-1694"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/72462"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Self-organizing maps for the identification of groundwater salinity sources based on hydrochemical data"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","224112"],["dc.bibliographiccitation.issue","22"],["dc.bibliographiccitation.journal","The Journal of Chemical Physics"],["dc.bibliographiccitation.volume","141"],["dc.contributor.author","Kordilla, Jannes"],["dc.contributor.author","Pan, Wenxiao"],["dc.contributor.author","Tartakovsky, Alexandre"],["dc.date.accessioned","2018-11-07T09:31:18Z"],["dc.date.available","2018-11-07T09:31:18Z"],["dc.date.issued","2014"],["dc.description.abstract","We propose a novel smoothed particle hydrodynamics (SPH) discretization of the fully coupled Landau-Lifshitz-Navier-Stokes (LLNS) and stochastic advection-diffusion equations. The accuracy of the SPH solution of the LLNS equations is demonstrated by comparing the scaling of velocity variance and the self-diffusion coefficient with kinetic temperature and particle mass obtained from the SPH simulations and analytical solutions. The spatial covariance of pressure and velocity fluctuations is found to be in a good agreement with theoretical models. To validate the accuracy of the SPH method for coupled LLNS and advection-diffusion equations, we simulate the interface between two miscible fluids. We study formation of the so-called \"giant fluctuations\" of the front between light and heavy fluids with and without gravity, where the light fluid lies on the top of the heavy fluid. We find that the power spectra of the simulated concentration field are in good agreement with the experiments and analytical solutions. In the absence of gravity, the power spectra decay as the power -4 of the wavenumber-except for small wavenumbers that diverge from this power law behavior due to the effect of finite domain size. Gravity suppresses the fluctuations, resulting in much weaker dependence of the power spectra on the wavenumber. Finally, the model is used to study the effect of thermal fluctuation on the Rayleigh-Taylor instability, an unstable dynamics of the front between a heavy fluid overlaying a light fluid. The front dynamics is shown to agree well with the analytical solutions. (C) 2014 AIP Publishing LLC."],["dc.identifier.doi","10.1063/1.4902238"],["dc.identifier.isi","000346272800013"],["dc.identifier.pmid","25494737"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/31509"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Inst Physics"],["dc.relation.issn","1089-7690"],["dc.relation.issn","0021-9606"],["dc.title","Smoothed particle hydrodynamics model for Landau-Lifshitz-Navier-Stokes and advection-diffusion equations"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Physical Review E"],["dc.bibliographiccitation.volume","96"],["dc.contributor.author","Shigorina, Elena"],["dc.contributor.author","Kordilla, Jannes"],["dc.contributor.author","Tartakovsky, Alexandre M."],["dc.date.accessioned","2020-12-10T18:25:36Z"],["dc.date.available","2020-12-10T18:25:36Z"],["dc.date.issued","2017"],["dc.identifier.doi","10.1103/PhysRevE.96.033115"],["dc.identifier.eissn","2470-0053"],["dc.identifier.issn","2470-0045"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/75758"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Smoothed particle hydrodynamics study of the roughness effect on contact angle and droplet flow"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Vadose Zone Journal"],["dc.bibliographiccitation.volume","18"],["dc.contributor.author","Shigorina, Elena"],["dc.contributor.author","Tartakovsky, Alexandre M."],["dc.contributor.author","Kordilla, Jannes"],["dc.date.accessioned","2019-07-04T08:33:12Z"],["dc.date.available","2019-07-04T08:33:12Z"],["dc.date.issued","2019"],["dc.description.abstract","This work investigates small-scale infiltration dynamics in smooth and rough single fractures using a three-dimensional multiphase pairwise-force smoothed particle hydrodynamics (PF-SPH) model. Gravity-driven infiltration instabilities in fractures under unsaturated conditions can significantly influence the arrival time of tracers or contaminants, and the rapid and localized recharge dynamics in fractured–porous aquifer systems. Here, we study the influence of roughness and injection rate on fluid flow modes and flow velocity. Three types of fractures are considered with different degrees of roughness, including a smooth fracture. Both the rough and smooth fractures exhibit flow instabilities, fingering, and intermittent flow regimes for low infiltration rates. In agreement with theoretical predictions, a flat fluid front is achieved when the flux q supplied to a fracture is larger than the gravitationally driven saturated flux [q > kρg/μcos(φ), where k is the intrinsic permeability of the fracture, ρ is a density, μ is the viscosity, and φ is the fracture inclination angle measured from the vertical direction]. To characterize the flow instability, we calculate standard deviations of velocity along the fracture width. For the considered infiltration rates, we find that an increase in roughness decreases the flow velocity and increases the standard deviation of velocity. This is caused by a higher likelihood of flow discontinuities in the form of fingering and/or snapping rivulets. To validate our unsaturated flow simulations in fractures, we estimate the scaling of specific discharge with normalized finger velocity, compute the relationship between fingertip length and scaled finger velocity, and find good agreement with experimental results."],["dc.identifier.doi","10.2136/vzj2018.08.0159"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/16238"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/58007"],["dc.language.iso","en"],["dc.notes.intern","Open Access"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.relation.issn","1539-1663"],["dc.rights","CC BY-NC-ND 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by-nc-nd/4.0"],["dc.title","Investigation of Gravity-Driven Infiltration Instabilities in Smooth and Rough Fractures Using a Pairwise-Force Smoothed Particle Hydrodynamics Model"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","9496"],["dc.bibliographiccitation.issue","11"],["dc.bibliographiccitation.journal","Water Resources Research"],["dc.bibliographiccitation.lastpage","9518"],["dc.bibliographiccitation.volume","53"],["dc.contributor.author","Kordilla, Jannes"],["dc.contributor.author","Noffz, Torsten"],["dc.contributor.author","Dentz, Marco"],["dc.contributor.author","Geyer, Tobias"],["dc.contributor.author","Tartakovsky, Alexandre M."],["dc.date.accessioned","2020-12-10T14:06:18Z"],["dc.date.available","2020-12-10T14:06:18Z"],["dc.date.issued","2017"],["dc.identifier.doi","10.1002/2016WR020236"],["dc.identifier.issn","0043-1397"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/69850"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Effect of Unsaturated Flow Modes on Partitioning Dynamics of Gravity-Driven Flow at a Simple Fracture Intersection: Laboratory Study and Three-Dimensional Smoothed Particle Hydrodynamics Simulations"],["dc.title.alternative","FLOW IN UNSATURATED FRACTURED MEDIA"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Water Resources Research"],["dc.bibliographiccitation.volume","57"],["dc.contributor.author","Shigorina, E."],["dc.contributor.author","Rüdiger, F."],["dc.contributor.author","Tartakovsky, A. M."],["dc.contributor.author","Sauter, M."],["dc.contributor.author","Kordilla, J."],["dc.date.accessioned","2021-06-01T09:41:37Z"],["dc.date.available","2021-06-01T09:41:37Z"],["dc.date.issued","2021"],["dc.identifier.doi","10.1029/2020WR027323"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/84983"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-425"],["dc.relation.eissn","1944-7973"],["dc.relation.issn","0043-1397"],["dc.title","Multiscale Smoothed Particle Hydrodynamics Model Development for Simulating Preferential Flow Dynamics in Fractured Porous Media"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.journal","Advances in Water Resources"],["dc.bibliographiccitation.lastpage","14"],["dc.bibliographiccitation.volume","59"],["dc.contributor.author","Kordilla, Jannes"],["dc.contributor.author","Tartakovsky, A. M."],["dc.contributor.author","Geyer, Tobias"],["dc.date.accessioned","2018-11-07T09:20:43Z"],["dc.date.available","2018-11-07T09:20:43Z"],["dc.date.issued","2013"],["dc.description.abstract","Flow on fracture surfaces has been identified by many authors as an important flow process in unsaturated fractured rock formations. Given the complexity of flow dynamics on such small scales, robust numerical methods have to be employed in order to capture the highly dynamic interfaces and flow intermittency. In this work we use a three-dimensional multiphase Smoothed Particle Hydrodynamics (SPH) model to simulate surface tension dominated flow on smooth fracture surfaces. We model droplet and film flow over a wide range of contact angles and Reynolds numbers encountered in such flows on rock surfaces. We validate our model via comparison with existing empirical and semi-analytical solutions for droplet flow. We use the SPH model to investigate the occurrence of adsorbed trailing films left behind droplets under various flow conditions and its importance for the flow dynamics when films and droplets coexist. It is shown that flow velocities are higher on prewetted surfaces covered by a thin film which is qualitatively attributed to the enhanced dynamic wetting and dewetting at the trailing and advancing contact lines. Finally, we demonstrate that the SPH model can be used to study flow on rough surfaces. (C) 2013 Elsevier Ltd. All rights reserved."],["dc.identifier.doi","10.1016/j.advwatres.2013.04.009"],["dc.identifier.isi","000323606500001"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/28942"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Elsevier Sci Ltd"],["dc.relation.issn","1872-9657"],["dc.relation.issn","0309-1708"],["dc.title","A smoothed particle hydrodynamics model for droplet and film flow on smooth and rough fracture surfaces"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Vadose Zone Journal"],["dc.bibliographiccitation.volume","18"],["dc.contributor.author","Noffz, Torsten"],["dc.contributor.author","Dentz, Marco"],["dc.contributor.author","Kordilla, Jannes"],["dc.date.accessioned","2019-07-09T11:50:27Z"],["dc.date.available","2019-07-09T11:50:27Z"],["dc.date.issued","2019"],["dc.description.abstract","Infiltration and recharge dynamics in fractured aquifer systems often strongly deviate from diffuse Darcy–Buckingham type flows due to the existence of a complex gravity-driven flow component along fractures, fracture networks, and fault zones. The formation of preferential flow paths in the unsaturated or vadose zone can trigger rapid mass fluxes, which are difficult to recover by volume-effective modeling approaches (e.g., the Richards equation) due to the nonlinear nature of free-surface flows and mass partitioning processes at unsaturated fracture intersections. In this study, well-controlled laboratory experiments enabled the isolation of single aspects of the mass redistribution process that ultimately affect travel time distributions across scales. We used custom-made acrylic cubes (20 by 20 by 20 cm) in analog percolation experiments to create simple wide-aperture fracture networks intersected by one or multiple horizontal fractures. A high-precision multichannel dispenser produced gravity-driven free-surface flow (droplets or rivulets) at flow rates ranging from 1 to 5 mL min−1. Total inflow rates were kept constant while the fluid was injected via 15 (droplet flow) or three inlets (rivulet flow) to reduce the impact of erratic flow dynamics. Normalized fracture inflow rates were calculated and compared for aperture widths of 1 and 2.5 mm. A higher efficiency in filling an unsaturated fracture by rivulet flow observed in former studies was confirmed. The onset of a capillary-driven Washburn-type flow was determined and recovered by an analytical solution. To upscale the dynamics and enable the prediction of mass partitioning for arbitrary-sized fracture cascades, a Gaussian transfer function was derived that reproduces the repetitive filling of fractures, where rivulet flow is the prevailing regime. Results show good agreement with experimental data for all tested aperture widths."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2019"],["dc.identifier.doi","10.2136/vzj2018.08.0155"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/15945"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59778"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.notes.intern","In goescholar not merged with http://resolver.sub.uni-goettingen.de/purl?gs-1/16068 but duplicate"],["dc.relation","info:eu-repo/grantAgreement/EC/FP7/617511/EU//MHETSCALE"],["dc.rights","CC BY-NC-ND 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by-nc-nd/4.0"],["dc.subject.ddc","550"],["dc.title","Analogue Fracture Experiments and Analytical Modeling of Unsaturated Percolation Dynamics in Fracture Cascades"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","593"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Zeitschrift der Deutschen Gesellschaft für Geowissenschaften"],["dc.bibliographiccitation.lastpage","615"],["dc.bibliographiccitation.volume","158"],["dc.contributor.author","Graue, Birte"],["dc.contributor.author","Kordilla, Jannes"],["dc.contributor.author","Siegesmund, Siegfried"],["dc.date.accessioned","2018-11-07T11:07:41Z"],["dc.date.available","2018-11-07T11:07:41Z"],["dc.date.issued","2007"],["dc.description.abstract","As part of an international research and conservation project at the ancient Egyptian tomb of Neferhotep (TT 49) from the 18(th) dynasty (1325 BC) in Thebes, stone deterioration is being surveyed and conservation is undertaken. This tomb is richly decorated with wall paintings, coloured bas relieves, and stone sculptures. Severe damage has been revealed: In particular the structural disintegration of the rock masses, that is a result of a clearly pronounced cataclastic overprint, has been a major structural problem since the tomb's origin. Deterioration phenomena are explained, such as structural damages, the extreme salt contamination in certain areas, and the deterioration of the surface of the stone. Furthermore specific material data of the natural stone are collected, for the clarification of deterioration phenomena and mechanisms as well as the development of conservation treatments. Therefore investigations are undertaken to gather mineralogical, structural, and petrological characteristics of the limestone. The discussion about the causes of damage and deterioration mechanisms reveals correlations between the findings of the survey and the investigations of the tomb, and anthropological, climatological, and petrographical influencing factors. From this discussion conclusions can be drawn leading to the formation of a conservation concept. The pronounced structural disintegration of the entire tomb has to be dealt with. Primarily the complete structure needs to be stabilized and then the surface should be treated. A climate monitoring is of crucial importance for the long-term preservation of the tomb with particular regard to it being made open to the public."],["dc.identifier.doi","10.1127/1860-1804/2007/0158-0593"],["dc.identifier.isi","000254994700015"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/52625"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation.issn","1860-1804"],["dc.relation.orgunit","Abteilung Strukturgeologie und Geodynamik"],["dc.title","Stone deterioration and conservation of the ancient Egyptian tomb of Neferhotep (TT 49) in Thebes (Egypt)"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Vadose Zone Journal"],["dc.bibliographiccitation.volume","21"],["dc.contributor.author","Rüdiger, Florian"],["dc.contributor.author","Dentz, Marco"],["dc.contributor.author","Nimmo, John"],["dc.contributor.author","Kordilla, Jannes"],["dc.date.accessioned","2022-04-01T10:02:14Z"],["dc.date.available","2022-04-01T10:02:14Z"],["dc.date.issued","2022"],["dc.description.sponsorship","Open-Access-Publikationsfonds 2022"],["dc.description.sponsorship","Open-Access-Publikationsfonds 2022"],["dc.identifier.doi","10.1002/vzj2.20177"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/105858"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-530"],["dc.relation.eissn","1539-1663"],["dc.relation.issn","1539-1663"],["dc.rights","CC BY 4.0"],["dc.title","Laboratory experiments and dual‐domain modeling of infiltration dynamics in partially saturated fractured porous media"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]