Abstract The effective mixing process is critical in biological and chemical processes. The main objective of the present study is to investigate the influence of normal and Halbach magnet arrays on the mixing performance of a three-inlet micromixer numerically. In this microdevice, ferrofluid is injected into the center inlet, and water is injected into two other inlets. The influence of Remanent Flux Density Norm (RFDN), number of magnets, magnet distance from the main microchannel entrance, and inlet flow rate is considered. It is revealed that the micromixer with magnets exhibits a 165% improvement in the mixing efficiency compared to the one with no magnetic field. The results show that increasing the magnetic field does not always increase the mixing quality. Even in some cases, it has a negative effect. It is demonstrated that the mixing efficiency is strongly influenced by the magnet arrangement. An optimal position is found for the magnet arrangement to achieve the maximum mixing efficiency of 91%. Contrary to the normal configuration, Halbach magnet array creates a parabolic profile for flux density. Halbach array can improve the mixing performance, depending on all magnets’ RFDN. The proposed microchannel can be used as a useful device for biological applications.

中文翻译：

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平面法向和Halbach磁体阵列对微混合影响的数值研究

摘要 在生物和化学过程中，有效的混合过程至关重要。本研究的主要目的是通过数值研究法线和 Halbach 磁体阵列对三入口微混合器混合性能的影响。在这个微型装置中，铁磁流体被注入中心入口，水被注入另外两个入口。考虑了剩余磁通密度范数 (RFDN)、磁铁数量、磁铁与主微通道入口的距离以及入口流速的影响。结果表明，与没有磁场的微型混合器相比，带磁铁的微型混合器的混合效率提高了 165%。结果表明，增加磁场并不总能提高混合质量。即使在某些情况下，它也会产生负面影响。结果表明，混合效率受磁铁排列的强烈影响。找到了磁铁布置的最佳位置，以实现 91% 的最大混合效率。与正常配置相反，Halbach 磁体阵列创建了磁通密度的抛物线轮廓。Halbach 阵列可以提高混合性能，这取决于所有磁铁的 RFDN。所提出的微通道可用作生物应用的有用装置。