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What are the fundamental principles of fluid mechanics that govern gas and liquid mixing in microchannels?

Compressibility

Mixing (physics)

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Gas and liquid mixing in microchannels is primarily governed by fluid mechanics principles such as laminar flow, convective diffusion, elasticity, viscosity, and compressibility. In microchannels, due to low hydraulic diameter and flow velocity, laminar flow dominates, hindering effective mixing. The mixing efficiency is influenced by factors like bend radius, dispersed phase fraction, and droplet velocity. Additionally, the interaction between elasticity and viscosity, along with compressibility effects, plays a crucial role in gas flow through microchannels. Numerical simulations using Navier–Stokes equations and quasigasdynamic equations help understand compressible flows in microchannels, essential for designing micro-electro-mechanical systems. These principles collectively impact the mixing performance in microchannels, crucial for various chemical engineering processes and technical systems.

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Journal Article•DOI Mixing efficiency and pressure drop analysis of liquid-liquid two phases flow in serpentine microchannels Jin-yuan Qian, Xiao-juan Li, Zhi-xin Gao, Zhi-jiang Jin - Show less +3 more 01 Sep 2019-Journal of Flow Chemistry 19 Citations	In microchannels, laminar flow affects mixing efficiency. Factors like bend radius and dispersed phase fraction influence mixing and pressure drop, crucial in microscale fluid mechanics.
Journal Article•DOI Transient gas flow in elastic microchannels Shai B. Elbaz, Hila Jacob, Amir D. Gat - Show less +2 more 01 Jul 2018-Journal of Fluid Mechanics 17 Citations	The fundamental principles governing gas flow in elastic microchannels include elasticity, viscosity, weak rarefaction, and low-Mach-number compressibility effects, crucial for understanding fluid mixing in microchannels.
Open access•Book Chapter•DOI Computational Fluid Dynamics of Mixing Performance in Microchannel Siti Nor Azreen Ahmad Termizi, Syamsul Rizal Abd Shukor - Show less +1 more 13 Dec 2019	Mixing in microchannels is primarily governed by fluid viscous effects, laminar flow, and convective diffusion. Diffusion plays a crucial role due to the absence of turbulence in microflows.
Patent Micro-channel fluid mixing unit, device and system Liu Dongren, Liu Xiao, Pan Dan, Jie Sun, Chen Hong, Xiaoyan Liu, Liu Hongzhao - Show less +6 more 29 Nov 2019 1 Citations	The micro-channel fluid mixing unit utilizes low impact loss rate, stable flow, and minimal driving force due to its micro-channel structure, enabling efficient multi-phase multi-component fluid mixing.

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