A paradox in Hele-Shaw displacements

  title={A paradox in Hele-Shaw displacements},
  author={Gelu Pacsa},
  • Gelu Pacsa
  • Published 17 July 2018
  • Physics
We study the Hele-Shaw immiscible displacements when all surfaces tensions on the interfaces are zero. The Saffman-Taylor instability occurs when a less viscous fluid is displacing a more viscous one, in a rectangular Hele-Shaw cell. We prove that an intermediate liquid with a variable viscosity can almost suppress this instability. On the contrary, a large number of constant viscosity liquid-layers inserted between the initial fluids gives us boundless growth rates with respect to the wave… 


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