A new benchmark for the secondary fluid flow through curved ducts. (2nd February 2022)

• Record Type: Journal Article
• Authors: Harding, Brendan
• Is Part Of: Chemical engineering science. Volume 248:Part B(2022)
• Publication Date: 2022-02-02
• Subjects: Dean flow -- Secondary flow magnitude -- Vortex pair -- Curved microfluidic ducts; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2021.117196
• Languages: English
• ISSNs: 0009-2509

Abstract

Highlights: We develop a new model of the secondary flow velocity in curved ducts. Our model respects the asymptotic scaling at low flow rates. Our model is very accurate over Dean numbers from 0 to 100. Discussion of why existing power law models are inappropriate. Illustration that our new model provides a significantly better benchmark. Abstract: Steady flow through curved ducts has numerous applications in the chemical engineering sciences. A recent example is within the field of microfluidics in which curved ducts have cross-section dimensions much smaller than one millimetre. The validation of steady fluid flow through curved microfluidic ducts is a crucial part of verifying any experimental work or numerical modelling in this field. Of particular interest is a measure of the secondary flow which consists of a counter-rotating vortex pair in the cross-sectional plane. We develop a new model for the magnitude of the secondary flow velocity within curved ducts having rectangular cross-sections. Our modelling respects the scaling at asymptotically small flow rates while carefully considering how this is modified for increasing Dean number. Lastly, we discuss why this new model is a more appropriate benchmark of the secondary flow than a power law model commonly found throughout the literature.