کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1803626 | 1024622 | 2009 | 6 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Magnetic separation from superparamagnetic particle suspensions Magnetic separation from superparamagnetic particle suspensions](/preview/png/1803626.png)
We investigate the magnetophoretic separation of magnetic microparticles from a non-dilute flow in a microfluidic channel and their subsequent field-induced aggregation under the influence of an externally applied magnetic force. This force induces dipolar interactions between the particles that aid in their separation from the flow. Existing analytical models for dilute suspensions cannot be extended to non-dilute suspensions in which interparticle magnetic interactions play an important role. We therefore conduct a parametric investigation of the mechanics of this problem in a microcapillary flow through simulations and experimental visualization. When a magnetic field is applied, the magnetic microparticles form an aggregate on the channel wall that is influenced by the competition between the holding magnetic force and the aggregate-depleting flow shear force. Microparticle collection in the aggregate increases linearly with increasing magnetic field strength and is characterized by distinct buildup and washaway phases. The collected microparticle volume fraction in an aggregate is found to depend on a single dimensional group that depends upon characteristic system parameters.
Journal: Journal of Magnetism and Magnetic Materials - Volume 321, Issue 14, July 2009, Pages 2251–2256