Instability of long fingers in Hele--Shaw flows

Journal Article · Sat Jun 01 00:00:00 EDT 1985 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.864947· OSTI ID:5755490

Park, C W; Homsy, G M

Experiments on steady fingers and their stability in Hele--Shaw cells, are reported. It is shown that the shape of steady fingers scales with a modified capillary number, Ca', as suggested by McLean and Saffman (J. Fluid. Mech. 102, 455 (1981) and our previous analysis (J. Fluid Mech. 139, 291 (1984)). The behavior at large Ca' is investigated by using a wide Hele--Shaw cell. It is observed that such fingers are unstable for Ca'>100, in agreement with the prediction by Taylor and Saffman (second symposium on naval hydrodynamics, 1958, p. 277) of instability as Ca'..-->..infinity. The mechanism is identified as one of tip-splitting, which occurs periodically in the weakly supercritical regime, and in a more complex fashion for large Ca'.

• Research Organization: Department of Chemical Engineering, Stanford University, Stanford, California 94305
• OSTI ID: 5755490
• Journal Information: Phys. Fluids; (United States), Vol. 28:6
• Country of Publication: United States
• Language: English

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TWO-PHASE FLOW
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PHOTOGRAPHY
SCALING LAWS
STEADY-STATE CONDITIONS
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ALCOHOLS
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420400* - Engineering- Heat Transfer & Fluid Flow