De Schryver Robin, El Cheikh Khadija, Lesage Karel, Yardimci Mert Yücel, De Schutter Geert
Magnel-Vandepitte Laboratory, Department of Structural Engineering and Building Materials, Faculty of Engineering and Architecture, Ghent University, Technologiepark-Zwijnaarde 60, B-9052 Ghent, Belgium.
Materials (Basel). 2021 Sep 2;14(17):5011. doi: 10.3390/ma14175011.
Rheological quantification is important in many industries, the concrete industry in particular, e.g., pumping, form filling, etc. Instead of performing expensive and time-consuming experiments, numerical simulations are a powerful means in view of rheological assessment. However, due to the unclear numerical reliability and the uncertainty of rheological input data, it is important for the construction industry to assess the numerical outcome. To reduce the numerical domain of cementitious suspensions, we assessed the numerical finite volume simulations of Bingham paste pumping flows in OpenFOAM. We analysed the numerical reliability, first, irrespective of its rheological input by comparison with the literature and theory, and second, dependent on a certain rheological quantification by comparison with pumping experiments. Irrespective of the rheological input, the numerical results were significantly accurate. Dependent on the rheological input, a numerical mismatch, however, existed. Errors below 1% can be expected for proposed numerical rules of thumb: a bi-viscous regularisation, with pressure numbers higher than 5/4. To improve bias due to uncertain rheology, a rheological configuration close to the engineer's aimed application should be used. However, important phenomena should not be overlooked. Further assessment for lubrication flows, in, e.g., concrete pumping, is still necessary to address concerns of reliability and stability.
流变学量化在许多行业中都很重要，尤其是混凝土行业，例如泵送、模板填充等。数值模拟是一种强大的手段，可用于流变学评估，而无需进行昂贵且耗时的实验。然而，由于数值可靠性不明确以及流变学输入数据的不确定性，对建筑行业来说评估数值结果很重要。为了缩小胶凝材料悬浮液的数值范围，我们评估了在OpenFOAM中对宾汉姆浆体泵送流动进行的数值有限体积模拟。我们首先通过与文献和理论比较来分析数值可靠性，这与流变学输入无关；其次通过与泵送实验比较来分析数值可靠性，这取决于特定的流变学量化。无论流变学输入如何，数值结果都相当准确。然而，取决于流变学输入，存在数值不匹配的情况。对于所提出数值经验法则（压力数高于5/4的双粘性正则化），预计误差低于1%。为了改善由于流变学不确定导致的偏差，应使用接近工程师目标应用的流变学配置。然而，重要现象不应被忽视。例如，对于混凝土泵送中的润滑流动，仍需要进一步评估，以解决可靠性和稳定性问题。
