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Dr.-Ing. Steffen Jesinghausen

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Publications
Dr.-Ing. Steffen Jesinghausen

Partikelverfahrenstechnik (PVT)

Second Head - Academic Senior Councillor - Senior Researcher

Phone:
+49 5251 60-3409
Fax:
+49 5251 60-3207
Office:
E3.122
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Visitor:
Pohlweg 55
33098 Paderborn

Open list in Research Information System

2023

Instabilities of Polymer Melt Suspensions under Uniaxial Extension (Poster)

M. Neukötter, S. Jesinghausen, H. Schmid. Instabilities of Polymer Melt Suspensions under Uniaxial Extension (Poster). In: International Congress on Rheology, Athens, 2023.


Experimental and simulative determination and correction of the effective gap extension in structured coaxial measuring systems

S. Josch, S. Jesinghausen, C. Dechert, H. Schmid, Rheologica Acta (2023)

<jats:title>Abstract</jats:title><jats:p>The use of structured measuring systems to prevent wall slip is a common approach to obtain absolute rheological values. Typically, only the minimum distance between the measuring surfaces is used for further calculation, implying that no flow occurs between the structural elements. But this assumption is misleading, and a gap correction is necessary. To determine the radius correction <jats:inline-formula><jats:alternatives><jats:tex-math>$$\Delta r$$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>Δ</mml:mi> <mml:mi>r</mml:mi> </mml:mrow> </mml:math></jats:alternatives></jats:inline-formula> for specific geometries, we conducted investigations on three Newtonian fluids (two silicon oils and one suspension considered to be Newtonian in the relevant shear rate range). The results show that <jats:inline-formula><jats:alternatives><jats:tex-math>$$\Delta r$$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>Δ</mml:mi> <mml:mi>r</mml:mi> </mml:mrow> </mml:math></jats:alternatives></jats:inline-formula> is not only shear- and material-independent, but geometry-dependent, providing a Newtonian flow behaviour in a similar viscosity range. Therefore, a correction value can be determined with only minute deviations in different Newtonian fluids. As the conducted laboratory measurements are very time-consuming and expensive, a CFD-approach with only very small deviations was additionally developed and compared for validation purposes. Therefore, simulation is an effective and resource-efficient alternative to the presented laboratory measurements to determine <jats:inline-formula><jats:alternatives><jats:tex-math>$$\Delta r$$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>Δ</mml:mi> <mml:mi>r</mml:mi> </mml:mrow> </mml:math></jats:alternatives></jats:inline-formula> for the correction of structured coaxial geometries even for non-Newtonian fluids in the future.</jats:p>


Development of an adaptive coaxial concrete rheometer and rheological characterisation of fresh concrete

S. Josch, S. Jesinghausen, H. Schmid, Applied Rheology (2023), 33(1)

<jats:title>Abstract</jats:title> <jats:p>The accessibility to rheological parameters for concrete is becoming more and more relevant. This is mainly related to the constantly emerging challenges, such as not only the development of high-strength concretes is progressing very fast but also the simulation of the flow behaviour is of high importance. The main problem, however, is that the rheological characterisation of fresh concrete is not possible via commercial rheometers. The so-called concrete rheometers provide valuable relative values for comparing different concretes, but they cannot measure absolute values. Therefore, we developed an adaptive coaxial concrete rheometer (ACCR) that allows the measurement of fresh concrete with particles up to <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/j_arh-2022-0140_eq_001.png" /> <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:msub> <m:mrow> <m:mi>d</m:mi> </m:mrow> <m:mrow> <m:mi mathvariant="normal">max</m:mi> </m:mrow> </m:msub> <m:mo>=</m:mo> <m:mn>5.5</m:mn> <m:mspace width=".5em" /> <m:mi mathvariant="normal">mm</m:mi> </m:math> <jats:tex-math>{d}_{{\rm{\max }}}=5.5\hspace{.5em}{\rm{mm}}</jats:tex-math> </jats:alternatives> </jats:inline-formula>. The comparison of the ACCR with a commercial rheometer showed very good agreement for selected test materials (Newtonian fluid, shear thinning fluid, suspension, and yield stress fluid), so that self-compacting concrete was subsequently measured. Since these measurements showed a very high reproducibility, the rheological properties of the fresh concrete could be determined with high accuracy. The common flow models (Bingham (B), Herschel–Bulkley, modified Bingham (MB) models) were also tested for their applicability, with the Bingham and the modified Bingham model proving to be the best suitable ones.</jats:p>


Particles as Seeds for Instabilities in Uniaxially Elongated Polymer Suspension Filaments (Presentation)

M. Neukötter, S. Jesinghausen, H. Schmid. Particles as Seeds for Instabilities in Uniaxially Elongated Polymer Suspension Filaments (Presentation). In: Annual Meeting of the German Rheological Society (DRG) , Berlin, 2023.


2022

Model droplet formation in extensional filament stretching within a Filament Extension Atomizer

M. Neukötter, S. Jesinghausen, H. Schmid, Rheologica Acta (2022)

<jats:title>Abstract</jats:title><jats:p>Further innovation in the field of selective laser sintering (SLS) is strongly connected to the availability of new materials since the market is dominated by polyamide 12 (&gt;90%). The aim of this publication is to develop a descriptive model for the droplet formation process in a Filament Extension Atomizer to predict the applicability to exploit further polymers for the SLS process. The feasibility was tested, investigated and characterized using a “Dripping out of a nozzle” setup for uniaxial extension. The droplet formation process was then observed via high-speed camera imaging and classified for certain parameters. The experiments were carried out using semi-diluted polyethylene oxide (600–4000 kg/mol), glycerol and water solutions as model fluids. Driven by the Plateau-Rayleigh instability, different types of spherical droplets were observed and various droplet formation mechanisms demonstrated and analyzed. Based on the experimental results, a predictive model is derived to describe various essential parameters.</jats:p>


Innovative Werkstoffherstellung für das Polymer Laser Sintern – Teil 2

M.J. Rüther, S.H. Klippstein, S. Ponusamy, S. Jesinghausen, H. Schmid, Werkstoffe (2022), 6, pp. 18 - 19


Innovative Werkstoffherstellung für das Polymer Laser Sintern – Teil 1

M.J. Rüther, S.H. Klippstein, S. Ponusamy, S. Jesinghausen, H. Schmid, Werkstoffe (2022), 5, pp. 28-29


Triggering instabilities of polymer solution suspensions under uniaxial extension (Presentation)

M. Neukötter, S. Jesinghausen, H. Schmid. Triggering instabilities of polymer solution suspensions under uniaxial extension (Presentation). In: Joint Online Symposium on Rheology, Digital, 2022.


Instability analysis of suspensions with a polymer solution matrix (Presentation)

M. Neukötter, S. Jesinghausen, H. Schmid. Instability analysis of suspensions with a polymer solution matrix (Presentation). In: Annual European Rheology Conference, Sevilla, 2022.


A novel correction method for the shear rate in a couette rheometer (Vortrag)

T. Rüther, S. Jesinghausen, H. Schmid. A novel correction method for the shear rate in a couette rheometer (Vortrag). In: AERC , Sevilla, 2022.


NEW CORRECTION APPROACHES FOR DETERMINING THE TRUE SHEAR RATE IN A COAXIAL-RHEOMETER (Vortrag)

T. Rüther, S. Jesinghausen, H. Schmid. NEW CORRECTION APPROACHES FOR DETERMINING THE TRUE SHEAR RATE IN A COAXIAL-RHEOMETER (Vortrag). In: Joint Online Symposium on Rheology 2022, 2022.


2021


Theoretische Beschreibung des Tropfenbildungsprozesses bei der Filament Extension Atomization: Entwicklung eines Vorhersagemodells für die Tropfengröße (Poster)

M. Neukötter, S. Jesinghausen, H. Schmid. Theoretische Beschreibung des Tropfenbildungsprozesses bei der Filament Extension Atomization: Entwicklung eines Vorhersagemodells für die Tropfengröße (Poster). In: Jahrestreffen der ProcessNet-Fachgruppen Computational Fluid Dynamics und Mehrphasenströmungen, Online, 2021.


Filament Extension Atomization – A novel Process for Powder Production? (Presentation)

M. Neukötter, S. Jesinghausen, H. Schmid. Filament Extension Atomization – A novel Process for Powder Production? (Presentation). In: Annual European Rheology Conference, Online, 2021.


2020

Interlaboratory study on rheological properties of cement pastes and reference substances: comparability of measurements performed with different rheometers and measurement geometries

M. Haist, J. Link, D. Nicia, S. Leinitz, C. Baumert, T. von Bronk, D. Cotardo, M. Eslami Pirharati, S. Fataei, H. Garrecht, C. Gehlen, I. Hauschildt, I. Ivanova, S. Jesinghausen, C. Klein, H. Krauss, L. Lohaus, D. Lowke, O. Mazanec, S. Pawelczyk, U. Pott, N.W. Radebe, J.J. Riedmiller, H. Schmid, W. Schmidt, E. Secrieru, D. Stephan, M. Thiedeitz, M. Wilhelm, V. Mechtcherine, Materials and Structures (2020)

This paper presents the results of an interlaboratory study of the rheological properties of cement paste and ultrasound gel as reference substance. The goal was to quantify the comparability and reproducibility of measurements of the Bingham parameters yield stress and plastic viscosity when measured on one specific paste composition and one particular ultrasound gel in different laboratories using different rheometers and measurement geometries. The procedures for both in preparing the cement paste and carrying out the rheological measurements on cement paste and ultrasound gel were carefully defined for all of the study’s participants. Different conversion schemes for comparing the results obtained with the different measurement setups are presented here and critically discussed. The procedure proposed in this paper ensured a reasonable comparability of the results with a coefficient of variation for the yield stress of 27% and for the plastic viscosity of 24%, despite the individual measurement series’ having been performed in different labs with different rheometers and measurement geometries.


Absolute Rheological Measurements of Model Suspensions: Influence and Correction of Wall Slip Prevention Measures

S. Pawelczyk, M. Kniepkamp, S. Jesinghausen, H. Schmid, Materials (2020), 467

<jats:p>Since suspensions (e.g., in food, cement, or cosmetics industries) tend to show wall slip, the application of structured measuring surfaces in rheometers is widespread. Usually, for parallel-plate geometries, the tip-to-tip distance is used for calculation of absolute rheological values, which implies that there is no flow behind this distance. However, several studies show that this is not true. Therefore, the measuring gap needs to be corrected by adding the effective gap extension δ to the prescribed gap height H in order to obtain absolute rheological properties. In this paper, we determine the effective gap extension δ for different structures and fluids (Newtonian, shear thinning, and model suspensions that can be adjusted to the behavior of real fluids) and compare the corrected values to reference data. We observe that for Newtonian fluids a gap- and material-independent correction function can be derived for every measuring system, which is also applicable to suspensions, but not to shear thinning fluids. Since this relation appears to be mainly dependent on the characteristics of flow behaviour, we show that the calibration of structured measuring systems is possible with Newtonian fluids and then can be transferred to suspensions up to a certain particle content.</jats:p>


2017


2016

Direct measurement of wall slip and slip layer thickness of non-Brownian hard-sphere suspensions in rectangular channel flows

S. Jesinghausen, R. Weiffen, H. Schmid, Experiments in Fluids (2016)

Wall slip is a long-known phenomenon in the field of rheology. Nevertheless, the origin and the evolution are not completely clear yet. Regarding suspensions, the effect becomes even more complicated, because different mechanisms like pure slip or slip due to particle migration have to be taken into account. Furthermore, suspensions themselves show many flow anomalies and the isolation of slip is complicated. In order to develop working physical models, further insight is necessary. In this work, we measured experimentally the wall slip velocities of different highly filled suspensions in a rectangular slit die directly with respect to the particle concentration and the particle size. The slip velocities were obtained using a particle image velocimetry (PIV) system. The suspensions consisting of a castor oil–cinnamon oil blend and PMMA particles were matched in terms of refractive indexes to appear transparent. Hereby, possible optical path lengths larger than 15 mm were achieved. The slip velocities were found to be in a quadratic relation to the wall shear stress. Furthermore, the overall flow rate as well as the particle concentration has a direct influence on the slip. Concerning the shear stress, there seem to be two regions of slip with different physical characteristics. Furthermore, we estimated the slip layer thickness directly from the velocity profiles and propose a new interpretation. The PIV technique is used to investigate the viscosity and implicit the concentration profile in the slit die. It is shown that the particle migration process is quite fast.


Open list in Research Information System

Forschungsgebiet

Rheologie

Lebenslauf

seit
2011
Oberingenieur am Lehrstuhl für Partikelverfahrenstechnik der Universität Paderborn
2017Promotion mit Auszeichnung an der Fakultät für Maschinenbau der Universität Paderborn im Bereich Rheologie mit dem Thema "Rheo-PIV nichtkollidaler Suspensionen: Strukturelle Untersuchungen der Strömungsentwicklung mit Fokus auf Wandgleiten"
2010 -
2011
Wissenschaftlicher Mitarbeiter am Lehrstuhl für Partikelverfahrenstechnik der Universität Paderborn
2003 - 2011Nebenberuflich Pflegekraft für Menschen mit Behinderung im „Haus Wilhelmshöhe“, Paderborn
2002 - 2003Zivildienst, Caritas Kurzzeitpflege für Menschen mit Behinderung Paderborn
2004 - 2010Maschinenbaustudium „Produktentwicklung“ an der Universität Paderborn mit den Schwerpunkten „Angewandte Mechanik“, „Umweltbetriebstechnik“ und „Energietechnik“. Diplomarbeit zu dem Thema: "Experimentelle Untersuchung der Abhängigkeit zwischen Synthesebedingungen und Partikeleigenschaften am Beispiel nanoskaligen Magnetits
2002Abitur an der „Alten Landesschule Korbach“

 

Veröffentlichungen


Open list in Research Information System

Josch S, Jesinghausen S, Schmid H-J. Development of an adaptive coaxial concrete rheometer and rheological characterisation of fresh concrete. Applied Rheology. 2023;33(1). doi:10.1515/arh-2022-0140

<jats:title>Abstract</jats:title> <jats:p>The accessibility to rheological parameters for concrete is becoming more and more relevant. This is mainly related to the constantly emerging challenges, such as not only the development of high-strength concretes is progressing very fast but also the simulation of the flow behaviour is of high importance. The main problem, however, is that the rheological characterisation of fresh concrete is not possible via commercial rheometers. The so-called concrete rheometers provide valuable relative values for comparing different concretes, but they cannot measure absolute values. Therefore, we developed an adaptive coaxial concrete rheometer (ACCR) that allows the measurement of fresh concrete with particles up to <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/j_arh-2022-0140_eq_001.png" /> <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:msub> <m:mrow> <m:mi>d</m:mi> </m:mrow> <m:mrow> <m:mi mathvariant="normal">max</m:mi> </m:mrow> </m:msub> <m:mo>=</m:mo> <m:mn>5.5</m:mn> <m:mspace width=".5em" /> <m:mi mathvariant="normal">mm</m:mi> </m:math> <jats:tex-math>{d}_{{\rm{\max }}}=5.5\hspace{.5em}{\rm{mm}}</jats:tex-math> </jats:alternatives> </jats:inline-formula>. The comparison of the ACCR with a commercial rheometer showed very good agreement for selected test materials (Newtonian fluid, shear thinning fluid, suspension, and yield stress fluid), so that self-compacting concrete was subsequently measured. Since these measurements showed a very high reproducibility, the rheological properties of the fresh concrete could be determined with high accuracy. The common flow models (Bingham (B), Herschel–Bulkley, modified Bingham (MB) models) were also tested for their applicability, with the Bingham and the modified Bingham model proving to be the best suitable ones.</jats:p>


Josch S, Jesinghausen S, Dechert C, Schmid H-J. Experimental and simulative determination and correction of the effective gap extension in structured coaxial measuring systems. Rheologica Acta. Published online 2023. doi:10.1007/s00397-023-01383-2

<jats:title>Abstract</jats:title><jats:p>The use of structured measuring systems to prevent wall slip is a common approach to obtain absolute rheological values. Typically, only the minimum distance between the measuring surfaces is used for further calculation, implying that no flow occurs between the structural elements. But this assumption is misleading, and a gap correction is necessary. To determine the radius correction <jats:inline-formula><jats:alternatives><jats:tex-math>$$\Delta r$$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>Δ</mml:mi> <mml:mi>r</mml:mi> </mml:mrow> </mml:math></jats:alternatives></jats:inline-formula> for specific geometries, we conducted investigations on three Newtonian fluids (two silicon oils and one suspension considered to be Newtonian in the relevant shear rate range). The results show that <jats:inline-formula><jats:alternatives><jats:tex-math>$$\Delta r$$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>Δ</mml:mi> <mml:mi>r</mml:mi> </mml:mrow> </mml:math></jats:alternatives></jats:inline-formula> is not only shear- and material-independent, but geometry-dependent, providing a Newtonian flow behaviour in a similar viscosity range. Therefore, a correction value can be determined with only minute deviations in different Newtonian fluids. As the conducted laboratory measurements are very time-consuming and expensive, a CFD-approach with only very small deviations was additionally developed and compared for validation purposes. Therefore, simulation is an effective and resource-efficient alternative to the presented laboratory measurements to determine <jats:inline-formula><jats:alternatives><jats:tex-math>$$\Delta r$$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>Δ</mml:mi> <mml:mi>r</mml:mi> </mml:mrow> </mml:math></jats:alternatives></jats:inline-formula> for the correction of structured coaxial geometries even for non-Newtonian fluids in the future.</jats:p>


Neukötter M, Jesinghausen S, Schmid H-J. Instabilities of Polymer Melt Suspensions under Uniaxial Extension (Poster). In: ; 2023.


Neukötter M, Jesinghausen S, Schmid H-J. Particles as Seeds for Instabilities in Uniaxially Elongated Polymer Suspension Filaments (Presentation). In: ; 2023.


Rüther T, Jesinghausen S, Schmid H-J. A novel correction method for the shear rate in a couette rheometer (Vortrag). In: ; 2022.


Rüther MJ, Klippstein SH, Ponusamy S, Jesinghausen S, Schmid H-J. Innovative Werkstoffherstellung für das Polymer Laser Sintern – Teil 1. Werkstoffe. 2022;5:28-29.


Rüther MJ, Klippstein SH, Ponusamy S, Jesinghausen S, Schmid H-J. Innovative Werkstoffherstellung für das Polymer Laser Sintern – Teil 2. Werkstoffe. 2022;6:18-19.


Neukötter M, Jesinghausen S, Schmid H-J. Instability analysis of suspensions with a polymer solution matrix (Presentation). In: ; 2022.


Neukötter M, Jesinghausen S, Schmid H-J. Model droplet formation in extensional filament stretching within a Filament Extension Atomizer. Rheologica Acta. Published online 2022. doi:10.1007/s00397-022-01339-y

<jats:title>Abstract</jats:title><jats:p>Further innovation in the field of selective laser sintering (SLS) is strongly connected to the availability of new materials since the market is dominated by polyamide 12 (&gt;90%). The aim of this publication is to develop a descriptive model for the droplet formation process in a Filament Extension Atomizer to predict the applicability to exploit further polymers for the SLS process. The feasibility was tested, investigated and characterized using a “Dripping out of a nozzle” setup for uniaxial extension. The droplet formation process was then observed via high-speed camera imaging and classified for certain parameters. The experiments were carried out using semi-diluted polyethylene oxide (600–4000 kg/mol), glycerol and water solutions as model fluids. Driven by the Plateau-Rayleigh instability, different types of spherical droplets were observed and various droplet formation mechanisms demonstrated and analyzed. Based on the experimental results, a predictive model is derived to describe various essential parameters.</jats:p>


Rüther T, Jesinghausen S, Schmid H-J. NEW CORRECTION APPROACHES FOR DETERMINING THE TRUE SHEAR RATE IN A COAXIAL-RHEOMETER (Vortrag). In: ; 2022.


Neukötter M, Jesinghausen S, Schmid H-J. Triggering instabilities of polymer solution suspensions under uniaxial extension  (Presentation). In: ; 2022.


Pawelczyk S, Jesinghausen S, Schmid H-J. Charakterisierung des Fließverhaltens von Frischbeton – Entwicklung eines adaptiven Rheometers (ACCR) und Einfluss von Maßnahmen zur Sedimentationsprävention.; 2021.


Neukötter M, Jesinghausen S, Schmid H-J. Filament Extension Atomization – A novel Process for Powder Production? (Presentation). In: ; 2021.


Neukötter M, Jesinghausen S, Schmid H-J. Theoretische Beschreibung des Tropfenbildungsprozesses bei der Filament Extension Atomization: Entwicklung eines Vorhersagemodells für die Tropfengröße (Poster). In: ; 2021.


Pawelczyk S, Kniepkamp M, Jesinghausen S, Schmid H-J. Absolute Rheological Measurements of Model Suspensions: Influence and Correction of Wall Slip Prevention Measures. Materials. Published online 2020. doi:10.3390/ma13020467

<jats:p>Since suspensions (e.g., in food, cement, or cosmetics industries) tend to show wall slip, the application of structured measuring surfaces in rheometers is widespread. Usually, for parallel-plate geometries, the tip-to-tip distance is used for calculation of absolute rheological values, which implies that there is no flow behind this distance. However, several studies show that this is not true. Therefore, the measuring gap needs to be corrected by adding the effective gap extension δ to the prescribed gap height H in order to obtain absolute rheological properties. In this paper, we determine the effective gap extension δ for different structures and fluids (Newtonian, shear thinning, and model suspensions that can be adjusted to the behavior of real fluids) and compare the corrected values to reference data. We observe that for Newtonian fluids a gap- and material-independent correction function can be derived for every measuring system, which is also applicable to suspensions, but not to shear thinning fluids. Since this relation appears to be mainly dependent on the characteristics of flow behaviour, we show that the calibration of structured measuring systems is possible with Newtonian fluids and then can be transferred to suspensions up to a certain particle content.</jats:p>


Haist M, Link J, Nicia D, et al. Interlaboratory study on rheological properties of cement pastes and reference substances: comparability of measurements performed with different rheometers and measurement geometries. Materials and Structures. Published online 2020. doi:10.1617/s11527-020-01477-w

This paper presents the results of an interlaboratory study of the rheological properties of cement paste and ultrasound gel as reference substance. The goal was to quantify the comparability and reproducibility of measurements of the Bingham parameters yield stress and plastic viscosity when measured on one specific paste composition and one particular ultrasound gel in different laboratories using different rheometers and measurement geometries. The procedures for both in preparing the cement paste and carrying out the rheological measurements on cement paste and ultrasound gel were carefully defined for all of the study’s participants. Different conversion schemes for comparing the results obtained with the different measurement setups are presented here and critically discussed. The procedure proposed in this paper ensured a reasonable comparability of the results with a coefficient of variation for the yield stress of 27% and for the plastic viscosity of 24%, despite the individual measurement series’ having been performed in different labs with different rheometers and measurement geometries.


Jesinghausen S. Rheo-PIV nichtkolloidaler Suspensionen: Strukturelle Untersuchungen der Strömungsentwicklung in Schlitzdüsen mit Fokus auf Wandgleiten. Vol 3. Shaker; 2017.


Jesinghausen S, Weiffen R, Schmid H-J. Direct measurement of wall slip and slip layer thickness of non-Brownian hard-sphere suspensions in rectangular channel flows. Experiments in Fluids. Published online 2016. doi:10.1007/s00348-016-2241-6

Wall slip is a long-known phenomenon in the field of rheology. Nevertheless, the origin and the evolution are not completely clear yet. Regarding suspensions, the effect becomes even more complicated, because different mechanisms like pure slip or slip due to particle migration have to be taken into account. Furthermore, suspensions themselves show many flow anomalies and the isolation of slip is complicated. In order to develop working physical models, further insight is necessary. In this work, we measured experimentally the wall slip velocities of different highly filled suspensions in a rectangular slit die directly with respect to the particle concentration and the particle size. The slip velocities were obtained using a particle image velocimetry (PIV) system. The suspensions consisting of a castor oil–cinnamon oil blend and PMMA particles were matched in terms of refractive indexes to appear transparent. Hereby, possible optical path lengths larger than 15 mm were achieved. The slip velocities were found to be in a quadratic relation to the wall shear stress. Furthermore, the overall flow rate as well as the particle concentration has a direct influence on the slip. Concerning the shear stress, there seem to be two regions of slip with different physical characteristics. Furthermore, we estimated the slip layer thickness directly from the velocity profiles and propose a new interpretation. The PIV technique is used to investigate the viscosity and implicit the concentration profile in the slit die. It is shown that the particle migration process is quite fast.


Open list in Research Information System

Vorträge und Poster

  • Sebastian Pawelczyk, Steffen Jesinghausen, Hans-Joachim Schmid
    Rheological characterization of fresh concrete – Development of an adaptive rheometer and influence of sedimentation prevention measures
    Annual European Rheology Conference, digital (2021)
     
  • Moritz Neukötter, Steffen Jesinghausen, Hans-Joachim Schmid
    Filament extension atomization – A novel process for powder production?
    Annual European Rheology Conference, digital (2021)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    Absolute rheological measurements of suspensions: Influence and correction of wall slip prevention measures
    International Congress of Rheology, digital (2020)
     
  • Sebastian Pawelczyk, Steffen Jesinghausen, Hans-Joachim Schmid
    Rheological characterization of fresh concrete: Development of an adaptive rheometer and influence of sedimentation prevention measuress
    International Congress of Rheology, digital (2020)
     
  • Sebastian, Pawelczyk, Steffen Jesinghausen, Hans-Joachim Schmid
    Wall slip and concentration measurements by means of modified PIV methods
    Annual European Rheology Conference, Portoroz, Slowenien (2019)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    Wall slip and concentration measurements by means of modified PIV methods
    Annual European Rheology Conference, Sorrento, Italien (2018)
     
  • Sven Pieper, Steffen Jesinghausen, Hans-Joachim Schmid
    Layer-formation of non-colloidal suspensions in a parallel plate rheometer under steady shear
    Annual European Rheology Conference, Kopenhagen, Dänemark (2017)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    Rheo PIV in Rectangular Channel Flows: Slip and Concentration Profiles of Non Brownian Suspensions
    International Congress on Rheology (ICR), Kyoto, Japan (2016)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    PIV Rheologie von Suspensionen in einer rechteckigen Schlitzdüse: Strömungsentwicklung und Wandgleiten
    Jahrestreffen des Fachausschusses "Rheologie" und Jahrestagung der deutschen Rheologischen Gesellschaft, Berlin, Deutschland (2016)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    Rheological characterization of transparent suspensions by means of the velocity profile from PTV/PIV measurements
    Annual European Rheology Conference, Karlsruhe, Deutschland (2014)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    Particle Image Velocimetry and its potential to improve the analysis of suspensions
    International Symposium on Food Rheology and Structure, Zürich, Schweiz, (2015)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    Possibilities and challenges of Rheo-PIV for highly filled suspensions in a slit die
    Annual European Rheology Conference, Nantes, Frankreich (2015)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    Rheological characterization of transparent suspensions by means of the velocity profile from PTV/PIV measurements
    Annual European Rheology Conference, Karlsruhe, Deutschland (2014)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    Highly filled viscoelastic fluids in a slit die: Optical measurements of rheological properties, particle migration and wall slip
    International Congress on Particle Technology (PARTEC), Nürnberg, Deutschland (2013)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    Untersuchung zur Korrelation des Zeta Potentials und der rheologischen Eigenschaften einer Suspension mittels FT-Rheologie
    Jahrestreffen des Fachausschusses "Rheologie", Hohenheim, Deutschland (2012)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    Optical measurement of rheological properties of suspensions in a semitransparent slit die
    International Congress on Rheology (ICR), Lissabon, Portugal (2012)
     
  • Steffen Jesinghausen, Hans-Joachim Schmid
    Rheologische Charakterisierung hoch-gefüllter Suspensionen unter kontinuierlichem Fluss mit Hilfe optischer Methoden
    Partikel/Matrix – Wechselwirkungen und Verbundwerkstoffe – PMP Kolloquium, Paderborn, Deutschland (2011)
     

Betreute studentische Arbeiten

2020

  • Lena Riedemann (Bachelorarbeit): "Maximierung des Energieeintrages durch ein Turbinenrad bei einem Intensivmischer"
  • Moritz Neukötter (Masterarbeit): "Theoretische Beschreibung des Tropfenbildungsprozess beim Filament Extension Atomizer: Entwicklung eines Vorhersagemodells für die Tropfengröße"

2019

  • Lukas Graute (Masterarbeit): "Evaluation eines „Filament Extension Atomizers“ und Modellierung des Tropfenbildungsprozesses"
  • Marie-Luise Kniepkamp (Masterarbeit): "Untersuchung des Einflusses strukturierter Platten auf rheologische Messungen: Modellierung und Korrektur"

2018

  • Benedikt Schmidt (Masterarbeit): "Untersuchung des Austrags- und Förderverhaltens von Hochleistungsbecherwerken für Ersatzbrennstoffe in der Zementindustrie"
  • Sebastian Pawelczyk (Masterarbeit): "Aufbau und Charakterisierung eines „Filament Extension Atomizers“ zur Pulverherstellung für den Polymer Lasersinter-Prozess"

2017

  • Moritz Rüther (Studienarbeit): "Entwicklung und Aufbau einer Modellbrauanlage"
  • Moritz Rüther (Projektarbeit): "Experimenteller Aufbau einer teilautomatisierten Bierbrauanlage zum Einsatz in der Lehre"
  • Sebastian Pawelczyk (Studienarbeit): "Entwicklung eines adaptiven Rheometers für Suspensionen mit Korngrößen bis 1 cm für den Einsatz in der wissenschaftlichen Betoncharakterisierung"

2016

  • Lukas Graute (Bachelorarbeit): "Untersuchung der Strömungsentwicklung von Suspensionen beim Einlauf in Schlitzdüsen unter Beeinflussung des Einlaufverhältnisses und der Strömungsgeschwindigkeit"

2015

  • Igor Uwarow (Projektarbeit): "Bestimmung der Temperaturabhängigkeit des Brechungsindex von PMMA Partikeln"

2014

  • Igor Uwarow (Bachelorarbeit): "Praktische Untersuchung der Einflussgrößen bei der Einfärbung und Dispergierung von vernetzten und unvernetzten PMMA Partikeln sowie deren mechanische Auswirkung auf die gefärbten Partikeln"
  • René Weiffen (Masterarbeit): "Untersuchung der Grenzen klassischer Wandgleitkorrekturen für Suspensionen mit optischen Methoden"

2011

  • Carsten Freymüller (Bachelorarbeit): "Entwicklung eines zweistufigen Siebkonzeptes in der Mähdrescherreinigung"
  • Wei Fu (Studienarbeit): "Theoretische Rührertypenauslegung zur Dispergierung und Vermischung von Klärschlamm auf Grundlage rheologischer Untersuchungen"
  • Xindao Mao (Bachelorarbeit): "Ermittlung von Lackierparametern für eine Laborlackieranlage zur Nachstellung des Farbtones von automobilen Serienanlagen"
     

 

Sonstige Aufgaben

  • Oberingenieur

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