How to characterize laminar flow in microchannels?
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Laminar flow in microchannels can be characterized using various parameters. One important dimensionless number is the Reynolds number (Re), which compares the inertial forces to the viscous forces in the flow. However, for converging-diverging microchannels (CDMCs), a new dimensionless number called ReG (Re · Gm) is found to be more appropriate for flow characterization . Another parameter that affects laminar flow in microchannels is the aspect ratio (AR), which is the ratio of the channel width to its height. The required development length (L) for laminar flow in microchannels with different ARs can be estimated using numerical methods and a general correlation . Additionally, the surface roughness of microchannels can also influence laminar flow and heat transfer. The Poiseuille number and Nusselt number of laminar flow in rough microchannels are found to depend on the cross-section shape and Reynolds number of the flow . The hydrodynamic characteristics of laminar flow in tortuous microchannels are also affected by geometrical parameters, such as the channel path and Reynolds number . Empirical studies have shown that laminar flow in microchannels follows the conventional Poiseuille flow theory, with the critical Reynolds number and Nusselt number depending on the aspect ratio .
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| Papers (5) | Insight |
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48 Citations | The paper discusses the characterization of laminar flow in microchannels by investigating flow resistance and thermal behavior in rectangular microchannels of different sizes and aspect ratios. |
8 Citations | The paper discusses the hydrodynamic characteristics of laminar flow in tortuous microchannels. It mentions that flow visualizations and time-resolved velocity measurements were performed to study the flow patterns and transition from steady to transient flow. However, it does not provide a specific characterization method for laminar flow in microchannels. |
| The paper discusses the characterization of laminar flow in microchannels by using the Poiseuille number and the Reynolds number. | |
13 Citations | The paper suggests using the dimensionless number ReG (Re · Gm) to characterize laminar flow in microchannels. |
| The paper provides a detailed numerical investigation on the required development length in laminar flow in microchannels with rectangular cross section and different aspect ratios. It does not specifically mention how to characterize laminar flow in microchannels. |
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