Numerical evaluation of stresses acting on particles in high-pressure microsystems using a Reynolds stress model. (17th February 2015)

• Record Type: Journal Article
• Authors: Beinert, S.; Gothsch, T.; Kwade, A.
• Is Part Of: Chemical engineering science. Volume 123(2015)
• Page Start: 197
• Page End: 206
• Publication Date: 2015-02-17
• Subjects: Simulations -- Multiphase -- Reynolds-stress model -- Stress analysis -- Dispersing; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2014.10.042
• Languages: English
• ISSNs: 0009-2509

Abstract

Abstract: In the present study a model was developed which enables to calculate the stress acting on particles induced by the fluid flow in microchannels. Computational fluid dynamics (CFD) was used to simulate the flow field in five different microchannel geometries. With the help of a Reynolds - stress model and a stationary particle tracking a quantification of stresses in different geometries at varying pressure differences is possible. Furthermore, the effect of cavitation which occurs if the fluid expands to ambient pressure was investigated. The mass flow rates determined by the simulations are in good agreement with the ones determined experimentally. Except for the z-channel the computed stresses are in good agreement with previously conducted dispersion experiments. Additionally, the computed fluid stress was compared with the calculated Kolmogorov length scale to validate the results. Abstract : Highlights: We investigate the multiphase flow fields of different micro-channels by CFD. A new model to calculate acting stresses on particles was used. Based on the Reynolds stress tensor and a stationary particle tracking a quantification of acting stresses was possible. Effect of steam and cavitation was reproduced. Peak stress seems to be the leading breakage mechanism in turbulent microchannels.