Topic
Hele-Shaw flow
About: Hele-Shaw flow is a research topic. Over the lifetime, 5451 publications have been published within this topic receiving 151320 citations.
Papers published on a yearly basis
Papers
More filters
•
01 Jan 1985
TL;DR: In this article, the authors define fundamental concepts and definitions of flow, including the concept of flow with heat interaction, generalized flow, and isentropic flow and normal shock wave.
Abstract: 1. Fundamental Concepts and Definitions. 2. Equation of Flow. 3. Isentropic Flow. 4. Normal Shock Waves. 5. Adiabatic Frictional Flow in a Constant-Area Duct. 6. Flow with Heat Interaction and Generalized Flow. 7. Two-Dimensional Waves. 8. Linearized Flow. 9. Method of Characteristics. 10. Computational Fluid Dynamics. 11. Methods of Experimental Measurements. Appendix: Tables and Figures. General References. Index.
311 citations
••
TL;DR: In this paper, the lattice Boltzmann method is applied to simulate the two-dimensional isothermal pressure driven microchannel flow, and two boundary treatment schemes are incorporated to investigate their impacts to the entire flow field.
Abstract: Microflow has become a popular field of interest due to the advent of microelectromechanical systems. In this work, the lattice Boltzmann method, a particle-based approach, is applied to simulate the two-dimensional isothermal pressure driven microchannel flow. Two boundary treatment schemes are incorporated to investigate their impacts to the entire flow field. We pay particular attention to the pressure and the slip velocity distributions along the channel in our simulation. We also look at the mass flow rate which is constant throughout the channel and the overall average velocity for the pressure-driven flow. In addition, we include a simulation of shear-driven flow in our results for verification. Our numerical results compare well with those obtained analytically and experimentally. From this study, we may conclude that the lattice Boltzmann method is an efficient approach for simulation of microflows.
309 citations
••
TL;DR: In this paper, a three-dimensional computational stability analysis of flow over a backward-facing step with an expansion ratio (outlet to inlet height) of 2 at Reynolds numbers between 450 and 1050 is presented.
Abstract: Results are reported from a three-dimensional computational stability analysis of flow over a backward-facing step with an expansion ratio (outlet to inlet height) of 2 at Reynolds numbers between 450 and 1050. The analysis shows that the first absolute linear instability of the steady two-dimensional flow is a steady three-dimensional bifurcation at a critical Reynolds number of 748. The critical eigenmode is localized to the primary separation bubble and has a flat roll structure with a spanwise wavelength of 6.9 step heights. The system is further shown to be absolutely stable to two-dimensional perturbations up to a Reynolds number of 1500. Stability spectra and visualizations of the global modes of the system are presented for representative Reynolds numbers.
308 citations
••
TL;DR: In this paper, the Lagrange approach is used to define reduced bases and the basis functions in this approach are obtained from the numerical solutions, and the feasibility of this method for flow control is demonstrated on boundary control problems in closed cavity and wall-bounded channel flows.
306 citations
••
TL;DR: In this paper, experimental observations of liquid microchannel flows are reviewed and results of computer experiments concerning channel entrance, wall slip, non-Newtonian fluid, surface roughness, viscous dissipation and turbulence effects on the friction factor are discussed.
Abstract: Experimental observations of liquid microchannel flows are reviewed and results of computer experiments concerning channel entrance, wall slip, non-Newtonian fluid, surface roughness, viscous dissipation and turbulence effects on the friction factor are discussed. The experimental findings are classified into three groups. Group I emphasizes 'flow instabilities' and group II points out 'viscosity changes' as the causes of deviations from the conventional flow theory for macrochannels. Group III caters to studies that did not detect any measurable differences between micro- and macroscale fluid flow behaviors. Based on numerical friction factor analyses, the entrance effect should be taken into account for any microfluidic system. It is a function of channel length, aspect ratio and the Reynolds number. Non-Newtonian fluid flow effects are expected to be important for polymeric liquids and particle suspension flows. The wall slip effect is negligible for liquid flows in microconduits. Significant surface roughness effects are a function of the Darcy number, the Reynolds number and cross-sectional configurations. For relatively low Reynolds numbers, Re < 2000, onset to turbulence has to be considered important because of possible geometric non-uniformities, e.g., a contraction and/or bend at the inlet to the microchannel. Channel-size effect on viscous dissipation turns out to be important for conduits with Dh < 100 µm.
300 citations