The kinematic-wave theory of particle settling in tube centrifuges has become a subject of scientific discussion. Specifically, the common assumption was made that the flow in a rotating tube of large length/diameter ratio can be treated in one-dimensional approximation. The respective results have been found in agreement with measurements. However, an analysis of the two-dimensional settling process performed in the limit of vanishing particle concentration led to some results that are not in accordance with the one-dimensional flow approximation, irrespective of the length/diameter ratio. It is the aim of the present investigation to gain a better understanding of the process. According to the analysis presented here, quasi-one-dimensional kinematic waves are embedded in a two-dimensional bulk flow that is governed by the continuity equation for the mixture plus the boundary conditions at the walls of the tube. The results based on simplification assumptions are compared with those of the one-dimensional flow approximation. Limiting cases, based on an elaborate analysis of three distinct settling models, are investigated analytically, and the plausibility of some of the respective results is evaluated also in the context of the one-dimensional approximation. Experimental observations, reported in the time span 2001 through 2008, are compared with analytical results obtained and presented. Further experimental work beyond this time span is also analyzed.

管式离心机中颗粒沉降的运动波理论已成为科学讨论的主题。具体地，通常的假设是，可以以一维近似来处理长径比大的旋转管中的流动。已经发现各个结果与测量结果一致。然而，对在消失颗粒浓度的极限下进行的二维沉降过程的分析导致一些结果，这些结果不符合一维流动近似，而与长度/直径比无关。本研究的目的是更好地了解该过程。根据此处提供的分析，准一维运动波嵌入二维整体流中，该二维体流由混合物的连续性方程以及管壁的边界条件决定。将基于简化假设的结果与一维流量近似的结果进行比较。基于对三种不同沉降模型的详尽分析，对极限情况进行了分析研究，并且还在一维近似的背景下评估了某些结果的合理性。将2001年至2008年这段时间报告的实验观察结果与获得的分析结果进行比较。还分析了超出此时间范围的进一步实验工作。将基于简化假设的结果与一维流量近似的结果进行比较。基于对三种不同沉降模型的详尽分析，对极限情况进行了分析研究，并且还在一维近似的背景下评估了某些结果的合理性。将2001年至2008年这段时间报告的实验观察结果与获得的分析结果进行比较。还分析了超出此时间范围的进一步实验工作。将基于简化假设的结果与一维流量近似的结果进行比较。基于对三种不同沉降模型的详尽分析，对极限情况进行了分析研究，并且还在一维近似的背景下评估了某些结果的合理性。将2001年至2008年这段时间报告的实验观察结果与获得的分析结果进行比较。还分析了超出此时间范围的进一步实验工作。并且在一维近似的背景下评估了一些相应结果的合理性。将2001年至2008年这段时间报告的实验观察结果与获得的分析结果进行比较。还分析了超出此时间范围的进一步实验工作。并且在一维近似的情况下评估了某些相应结果的合理性。将2001年至2008年这段时间报告的实验观察结果与获得的分析结果进行比较。还分析了超出此时间范围的进一步实验工作。