Il Nuovo Cimento D

, Volume 8, Issue 2, pp 177–192 | Cite as

Electrohydrodynamic stability of a fluid layer. Effect of a tangential periodic field

  • Abou El Magd A. Mohamed
  • El Sayed F. El hehawey
  • Yusry O. El Dib
Article

Summary

The electrohydrodynamic stability of a fluid layer influenced by a periodic tangential electric field is studied. The model allows for general forms of deformations of the interface. Two simultaneous ordinary differential equations of Mathieu type are obtained. The coupled equations are solved by the method of multiple-scale perturbations for small electric-field amplitude and stability conditions are discussed. It is found that the tangential field has a stabilizing effect except at resonance points. Graphs are drawn to illustrate the resonance regions in a parameter space. The tangential periodic field cannot stabilize a system which is unstable under a constant electric field.

PACS. 68.10

Fluid surfaces and fluid-fluid interfaces 

Riassunto

Si studia la stabilità elettrodinamica di una strato fluido influenzato da un campo elettrico tangente periodico. II modello tien conto delle forme generali di deformazioni dell’interfaccia. Si ottengono due equazioni simultanee differenziali ordinarie del tipo di Mathieu. Le equazioni accoppiate sono risolte col metodo delle perturbazioni su scala multipla per piccola ampiezza di campo, elettrico e si dicutono le condizioni di stabilità. Si è trovato che il campo tangente, ha un effetto stabilizzante eccetto nei punti di risonanza. I grafici sono fatti per illustrare le regioni di risonanza in uno spazio di parametri. Il campo periodico tangente non può stabilizzare un, sistema che è instabile in un campo elettrico costante.

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Copyright information

© Società Italiana di Fisica 1986

Authors and Affiliations

  • Abou El Magd A. Mohamed
    • 1
  • El Sayed F. El hehawey
    • 1
  • Yusry O. El Dib
    • 1
  1. 1.Department of Mathematics, Faculty of EducationAin Shams University HeliopolisCairoEgypt

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