---
_id: '36983'
abstract:
- lang: eng
  text: "<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\">\r\n
    \               <mml:mrow>\r\n                  <mml:mi>Δ</mml:mi>\r\n                  <mml:mi>r</mml:mi>\r\n
    \               </mml:mrow>\r\n              </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\">\r\n
    \               <mml:mrow>\r\n                  <mml:mi>Δ</mml:mi>\r\n                  <mml:mi>r</mml:mi>\r\n
    \               </mml:mrow>\r\n              </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\">\r\n
    \               <mml:mrow>\r\n                  <mml:mi>Δ</mml:mi>\r\n                  <mml:mi>r</mml:mi>\r\n
    \               </mml:mrow>\r\n              </mml:math></jats:alternatives></jats:inline-formula>
    for the correction of structured coaxial geometries even for non-Newtonian fluids
    in the future.</jats:p>"
article_type: original
author:
- first_name: Sebastian
  full_name: Josch, Sebastian
  id: '38243'
  last_name: Josch
- first_name: Steffen
  full_name: Jesinghausen, Steffen
  id: '3959'
  last_name: Jesinghausen
  orcid: https://orcid.org/0000-0003-2611-5298
- first_name: Christopher
  full_name: Dechert, Christopher
  id: '69828'
  last_name: Dechert
- first_name: Hans-Joachim
  full_name: Schmid, Hans-Joachim
  id: '464'
  last_name: Schmid
  orcid: 000-0001-8590-1921
citation:
  ama: 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. <i>Rheologica Acta</i>. Published online 2023. doi:<a href="https://doi.org/10.1007/s00397-023-01383-2">10.1007/s00397-023-01383-2</a>
  apa: Josch, S., Jesinghausen, S., Dechert, C., &#38; Schmid, H.-J. (2023). Experimental
    and simulative determination and correction of the effective gap extension in
    structured coaxial measuring systems. <i>Rheologica Acta</i>. <a href="https://doi.org/10.1007/s00397-023-01383-2">https://doi.org/10.1007/s00397-023-01383-2</a>
  bibtex: '@article{Josch_Jesinghausen_Dechert_Schmid_2023, title={Experimental and
    simulative determination and correction of the effective gap extension in structured
    coaxial measuring systems}, DOI={<a href="https://doi.org/10.1007/s00397-023-01383-2">10.1007/s00397-023-01383-2</a>},
    journal={Rheologica Acta}, publisher={Springer Science and Business Media LLC},
    author={Josch, Sebastian and Jesinghausen, Steffen and Dechert, Christopher and
    Schmid, Hans-Joachim}, year={2023} }'
  chicago: Josch, Sebastian, Steffen Jesinghausen, Christopher Dechert, and Hans-Joachim
    Schmid. “Experimental and Simulative Determination and Correction of the Effective
    Gap Extension in Structured Coaxial Measuring Systems.” <i>Rheologica Acta</i>,
    2023. <a href="https://doi.org/10.1007/s00397-023-01383-2">https://doi.org/10.1007/s00397-023-01383-2</a>.
  ieee: 'S. Josch, S. Jesinghausen, C. Dechert, and H.-J. Schmid, “Experimental and
    simulative determination and correction of the effective gap extension in structured
    coaxial measuring systems,” <i>Rheologica Acta</i>, 2023, doi: <a href="https://doi.org/10.1007/s00397-023-01383-2">10.1007/s00397-023-01383-2</a>.'
  mla: Josch, Sebastian, et al. “Experimental and Simulative Determination and Correction
    of the Effective Gap Extension in Structured Coaxial Measuring Systems.” <i>Rheologica
    Acta</i>, Springer Science and Business Media LLC, 2023, doi:<a href="https://doi.org/10.1007/s00397-023-01383-2">10.1007/s00397-023-01383-2</a>.
  short: S. Josch, S. Jesinghausen, C. Dechert, H.-J. Schmid, Rheologica Acta (2023).
date_created: 2023-01-17T08:04:24Z
date_updated: 2023-03-14T07:41:28Z
department:
- _id: '150'
doi: 10.1007/s00397-023-01383-2
keyword:
- rheology
- rheometry
- suspension
- coaxial
- correction
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://link.springer.com/article/10.1007/s00397-023-01383-2
oa: '1'
publication: Rheologica Acta
publication_identifier:
  issn:
  - 0035-4511
  - 1435-1528
publication_status: published
publisher: Springer Science and Business Media LLC
quality_controlled: '1'
status: public
title: Experimental and simulative determination and correction of the effective gap
  extension in structured coaxial measuring systems
type: journal_article
user_id: '3959'
year: '2023'
...
---
_id: '43034'
abstract:
- lang: eng
  text: "<jats:title>Abstract</jats:title>\r\n               <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>\r\n                     <jats:alternatives>\r\n
    \                       <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\"
    xlink:href=\"graphic/j_arh-2022-0140_eq_001.png\" />\r\n                        <m:math
    xmlns:m=\"http://www.w3.org/1998/Math/MathML\">\r\n                           <m:msub>\r\n
    \                             <m:mrow>\r\n                                 <m:mi>d</m:mi>\r\n
    \                             </m:mrow>\r\n                              <m:mrow>\r\n
    \                                <m:mi mathvariant=\"normal\">max</m:mi>\r\n                              </m:mrow>\r\n
    \                          </m:msub>\r\n                           <m:mo>=</m:mo>\r\n
    \                          <m:mn>5.5</m:mn>\r\n                           <m:mspace
    width=\".5em\" />\r\n                           <m:mi mathvariant=\"normal\">mm</m:mi>\r\n
    \                       </m:math>\r\n                        <jats:tex-math>{d}_{{\\rm{\\max
    }}}=5.5\\hspace{.5em}{\\rm{mm}}</jats:tex-math>\r\n                     </jats:alternatives>\r\n
    \                 </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>"
author:
- first_name: Sebastian
  full_name: Josch, Sebastian
  id: '38243'
  last_name: Josch
- first_name: Steffen
  full_name: Jesinghausen, Steffen
  id: '3959'
  last_name: Jesinghausen
  orcid: https://orcid.org/0000-0003-2611-5298
- first_name: Hans-Joachim
  full_name: Schmid, Hans-Joachim
  id: '464'
  last_name: Schmid
  orcid: 000-0001-8590-1921
citation:
  ama: Josch S, Jesinghausen S, Schmid H-J. Development of an adaptive coaxial concrete
    rheometer and rheological characterisation of fresh concrete. <i>Applied Rheology</i>.
    2023;33(1). doi:<a href="https://doi.org/10.1515/arh-2022-0140">10.1515/arh-2022-0140</a>
  apa: Josch, S., Jesinghausen, S., &#38; Schmid, H.-J. (2023). Development of an
    adaptive coaxial concrete rheometer and rheological characterisation of fresh
    concrete. <i>Applied Rheology</i>, <i>33</i>(1). <a href="https://doi.org/10.1515/arh-2022-0140">https://doi.org/10.1515/arh-2022-0140</a>
  bibtex: '@article{Josch_Jesinghausen_Schmid_2023, title={Development of an adaptive
    coaxial concrete rheometer and rheological characterisation of fresh concrete},
    volume={33}, DOI={<a href="https://doi.org/10.1515/arh-2022-0140">10.1515/arh-2022-0140</a>},
    number={1}, journal={Applied Rheology}, publisher={Walter de Gruyter GmbH}, author={Josch,
    Sebastian and Jesinghausen, Steffen and Schmid, Hans-Joachim}, year={2023} }'
  chicago: Josch, Sebastian, Steffen Jesinghausen, and Hans-Joachim Schmid. “Development
    of an Adaptive Coaxial Concrete Rheometer and Rheological Characterisation of
    Fresh Concrete.” <i>Applied Rheology</i> 33, no. 1 (2023). <a href="https://doi.org/10.1515/arh-2022-0140">https://doi.org/10.1515/arh-2022-0140</a>.
  ieee: 'S. Josch, S. Jesinghausen, and H.-J. Schmid, “Development of an adaptive
    coaxial concrete rheometer and rheological characterisation of fresh concrete,”
    <i>Applied Rheology</i>, vol. 33, no. 1, 2023, doi: <a href="https://doi.org/10.1515/arh-2022-0140">10.1515/arh-2022-0140</a>.'
  mla: Josch, Sebastian, et al. “Development of an Adaptive Coaxial Concrete Rheometer
    and Rheological Characterisation of Fresh Concrete.” <i>Applied Rheology</i>,
    vol. 33, no. 1, Walter de Gruyter GmbH, 2023, doi:<a href="https://doi.org/10.1515/arh-2022-0140">10.1515/arh-2022-0140</a>.
  short: S. Josch, S. Jesinghausen, H.-J. Schmid, Applied Rheology 33 (2023).
date_created: 2023-03-16T19:06:49Z
date_updated: 2023-04-27T11:19:08Z
department:
- _id: '150'
doi: 10.1515/arh-2022-0140
intvolume: '        33'
issue: '1'
keyword:
- Condensed Matter Physics
- General Materials Science
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://www.degruyter.com/document/doi/10.1515/arh-2022-0140/html
oa: '1'
publication: Applied Rheology
publication_identifier:
  issn:
  - 1617-8106
publication_status: published
publisher: Walter de Gruyter GmbH
quality_controlled: '1'
status: public
title: Development of an adaptive coaxial concrete rheometer and rheological characterisation
  of fresh concrete
type: journal_article
user_id: '3959'
volume: 33
year: '2023'
...
---
_id: '24202'
author:
- first_name: Sebastian
  full_name: Pawelczyk, Sebastian
  id: '38243'
  last_name: Pawelczyk
- first_name: Steffen
  full_name: Jesinghausen, Steffen
  id: '3959'
  last_name: Jesinghausen
- first_name: Hans-Joachim
  full_name: Schmid, Hans-Joachim
  id: '464'
  last_name: Schmid
citation:
  ama: Pawelczyk S, Jesinghausen S, Schmid H-J. <i>Charakterisierung des Fließverhaltens
    von Frischbeton – Entwicklung eines adaptiven Rheometers (ACCR) und Einfluss von
    Maßnahmen zur Sedimentationsprävention</i>.; 2021.
  apa: Pawelczyk, S., Jesinghausen, S., &#38; Schmid, H.-J. (2021). <i>Charakterisierung
    des Fließverhaltens von Frischbeton – Entwicklung eines adaptiven Rheometers (ACCR)
    und Einfluss von Maßnahmen zur Sedimentationsprävention</i>.
  bibtex: '@book{Pawelczyk_Jesinghausen_Schmid_2021, place={Digitales Jahrestreffen
    der ProcessNet Fachgruppen MPH und CFD}, title={Charakterisierung des Fließverhaltens
    von Frischbeton – Entwicklung eines adaptiven Rheometers (ACCR) und Einfluss von
    Maßnahmen zur Sedimentationsprävention}, author={Pawelczyk, Sebastian and Jesinghausen,
    Steffen and Schmid, Hans-Joachim}, year={2021} }'
  chicago: Pawelczyk, Sebastian, Steffen Jesinghausen, and Hans-Joachim Schmid. <i>Charakterisierung
    des Fließverhaltens von Frischbeton – Entwicklung eines adaptiven Rheometers (ACCR)
    und Einfluss von Maßnahmen zur Sedimentationsprävention</i>. Digitales Jahrestreffen
    der ProcessNet Fachgruppen MPH und CFD, 2021.
  ieee: S. Pawelczyk, S. Jesinghausen, and H.-J. Schmid, <i>Charakterisierung des
    Fließverhaltens von Frischbeton – Entwicklung eines adaptiven Rheometers (ACCR)
    und Einfluss von Maßnahmen zur Sedimentationsprävention</i>. Digitales Jahrestreffen
    der ProcessNet Fachgruppen MPH und CFD, 2021.
  mla: Pawelczyk, Sebastian, et al. <i>Charakterisierung des Fließverhaltens von Frischbeton
    – Entwicklung eines adaptiven Rheometers (ACCR) und Einfluss von Maßnahmen zur
    Sedimentationsprävention</i>. 2021.
  short: S. Pawelczyk, S. Jesinghausen, H.-J. Schmid, Charakterisierung des Fließverhaltens
    von Frischbeton – Entwicklung eines adaptiven Rheometers (ACCR) und Einfluss von
    Maßnahmen zur Sedimentationsprävention, Digitales Jahrestreffen der ProcessNet
    Fachgruppen MPH und CFD, 2021.
date_created: 2021-09-13T07:52:49Z
date_updated: 2022-09-13T07:04:04Z
ddc:
- '540'
- '530'
department:
- _id: '150'
file:
- access_level: closed
  content_type: application/pdf
  creator: spawelcz
  date_created: 2021-09-13T07:47:53Z
  date_updated: 2021-09-13T07:47:53Z
  file_id: '24205'
  file_name: Charakterisierung des Fließverhaltens von Frischbeton.pdf
  file_size: 1743037
  relation: main_file
  success: 1
file_date_updated: 2021-09-13T07:47:53Z
has_accepted_license: '1'
language:
- iso: ger
place: Digitales Jahrestreffen der ProcessNet Fachgruppen MPH und CFD
status: public
supervisor:
- first_name: Steffen
  full_name: Jesinghausen, Steffen
  id: '3959'
  last_name: Jesinghausen
- first_name: Hans-Joachim
  full_name: Schmid, Hans-Joachim
  id: '464'
  last_name: Schmid
title: Charakterisierung des Fließverhaltens von Frischbeton – Entwicklung eines adaptiven
  Rheometers (ACCR) und Einfluss von Maßnahmen zur Sedimentationsprävention
type: misc
user_id: '38243'
year: '2021'
...
---
_id: '21948'
abstract:
- lang: eng
  text: <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>
article_number: '467'
article_type: original
author:
- first_name: Sebastian
  full_name: Pawelczyk, Sebastian
  id: '38243'
  last_name: Pawelczyk
- first_name: Marieluise
  full_name: Kniepkamp, Marieluise
  last_name: Kniepkamp
- first_name: Steffen
  full_name: Jesinghausen, Steffen
  id: '3959'
  last_name: Jesinghausen
  orcid: https://orcid.org/0000-0003-2611-5298
- first_name: Hans-Joachim
  full_name: Schmid, Hans-Joachim
  id: '464'
  last_name: Schmid
citation:
  ama: 'Pawelczyk S, Kniepkamp M, Jesinghausen S, Schmid H-J. Absolute Rheological
    Measurements of Model Suspensions: Influence and Correction of Wall Slip Prevention
    Measures. <i>Materials</i>. Published online 2020. doi:<a href="https://doi.org/10.3390/ma13020467">10.3390/ma13020467</a>'
  apa: 'Pawelczyk, S., Kniepkamp, M., Jesinghausen, S., &#38; Schmid, H.-J. (2020).
    Absolute Rheological Measurements of Model Suspensions: Influence and Correction
    of Wall Slip Prevention Measures. <i>Materials</i>, Article 467. <a href="https://doi.org/10.3390/ma13020467">https://doi.org/10.3390/ma13020467</a>'
  bibtex: '@article{Pawelczyk_Kniepkamp_Jesinghausen_Schmid_2020, title={Absolute
    Rheological Measurements of Model Suspensions: Influence and Correction of Wall
    Slip Prevention Measures}, DOI={<a href="https://doi.org/10.3390/ma13020467">10.3390/ma13020467</a>},
    number={467}, journal={Materials}, author={Pawelczyk, Sebastian and Kniepkamp,
    Marieluise and Jesinghausen, Steffen and Schmid, Hans-Joachim}, year={2020} }'
  chicago: 'Pawelczyk, Sebastian, Marieluise Kniepkamp, Steffen Jesinghausen, and
    Hans-Joachim Schmid. “Absolute Rheological Measurements of Model Suspensions:
    Influence and Correction of Wall Slip Prevention Measures.” <i>Materials</i>,
    2020. <a href="https://doi.org/10.3390/ma13020467">https://doi.org/10.3390/ma13020467</a>.'
  ieee: 'S. Pawelczyk, M. Kniepkamp, S. Jesinghausen, and H.-J. Schmid, “Absolute
    Rheological Measurements of Model Suspensions: Influence and Correction of Wall
    Slip Prevention Measures,” <i>Materials</i>, Art. no. 467, 2020, doi: <a href="https://doi.org/10.3390/ma13020467">10.3390/ma13020467</a>.'
  mla: 'Pawelczyk, Sebastian, et al. “Absolute Rheological Measurements of Model Suspensions:
    Influence and Correction of Wall Slip Prevention Measures.” <i>Materials</i>,
    467, 2020, doi:<a href="https://doi.org/10.3390/ma13020467">10.3390/ma13020467</a>.'
  short: S. Pawelczyk, M. Kniepkamp, S. Jesinghausen, H.-J. Schmid, Materials (2020).
date_created: 2021-05-04T08:48:48Z
date_updated: 2023-01-17T07:45:59Z
department:
- _id: '150'
doi: 10.3390/ma13020467
keyword:
- wall slip prevention
- effective gap height
- parallel-plate system
- structured surfaces
- model suspensions
- cement paste
- fresh concrete
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://www.mdpi.com/1996-1944/13/2/467
oa: '1'
publication: Materials
publication_identifier:
  issn:
  - 1996-1944
publication_status: published
quality_controlled: '1'
status: public
title: 'Absolute Rheological Measurements of Model Suspensions: Influence and Correction
  of Wall Slip Prevention Measures'
type: journal_article
user_id: '3959'
year: '2020'
...