Loading...

Rotational regimes of freely suspended liquid crystal films under electric current in presence of an external electric field

Shirsavar, R ; Sharif University of Technology | 2012

995 Viewed
  1. Type of Document: Article
  2. DOI: 10.1007/s10404-012-0943-5
  3. Publisher: 2012
  4. Abstract:
  5. The electrohydrodynamic (EHD) vortices produced by an electric current in freely suspended liquid crystal (LC) films of N-(4-methoxybenzylidene)-4- butylaniline (MBBA), convert to a pure rotation in the presence of external electric field (E ext) perpendicular to the current direction. Here, the direction and strength of the rotation are precisely under control by our self-made device called "liquid-film motor". In this paper, we present experimental observations of the EHD fluid flow when external electric field varies from zero to a value in which pure rotation on the liquid crystal (LC) film is observed. We also show experimentally that the presence of external electric field causes a great decrease in the current produced by the voltage V J required for observing EHD vortices in freely suspended films of MBBA. The LC films begin to rotate when E ext V J reaches a threshold value. This threshold is investigated experimentally as a function of voltage V J and the external electrical field (E ext)
  6. Keywords:
  7. Fluid film motor ; Nematic liquid crystal ; Vortex ; Current direction ; Electeronematic effect ; Electrical field ; Experimental observation ; External electric field ; Fluid films ; Freely suspended film ; Liquid crystal films ; Pure-rotation ; Electrohydrodynamics ; Liquid films ; Nematic liquid crystals ; Organic compounds ; Vortex flow
  8. Source: Microfluidics and Nanofluidics ; Volume 13, Issue 1 , 2012 , Pages 83-89 ; 16134982 (ISSN)
  9. URL: http://link.springer.com/article/10.1007%2Fs10404-012-0943-5