Joule heating effects in electrokinetically driven flow through rectangular microchannels: An analytical approach

Sadeghi, A ; Sharif University of Technology | 2013

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  1. Type of Document: Article
  2. DOI: 10.1080/15567265.2013.776150
  3. Publisher: 2013
  4. Abstract:
  5. This is a theoretical study dealing with mixed electroosmotic and pressure-driven flow of a Newtonian liquid in a rectangular microchannel. Both and thermal boundary conditions are considered and the Debye-Hückel linearization is invoked. The governing equations are made dimensionless assuming fully developed conditions and then analytically solved using an infinite series solution. The governing factors are found to be the dimensionless Debye-Hückel parameter, velocity scale ratio, dimensionless Joule heating parameter, and channel aspect ratio. The results indicate that the Nusselt number is an increasing function of the channel aspect ratio, whereas the opposite is true for the velocity scale ratio. In addition, unless a sufficiently high opposed pressure is present, a higher Joule heating rate is generally accompanied by a lower Nusselt number. Moreover, increasing the dimensionless Debye-Hückel parameter gives rise to a higher Nusselt number, unless a high value of the channel aspect ratio with surface heating is considered
  6. Keywords:
  7. Convection ; Electroosmotic flow ; Joule heating ; Microchannel ; Analytical approach ; Channel aspect ratios ; Increasing functions ; Joule heating effect ; Pressure-driven flows ; Rectangular microchannels ; Thermal boundary conditions ; Aspect ratio ; Electroosmosis ; Heat convection ; Microchannels ; Newtonian liquids ; Nusselt number
  8. Source: Nanoscale and Microscale Thermophysical Engineering ; Volume 17, Issue 3 , 2013 , Pages 173-193 ; 15567265 (ISSN)
  9. URL: http://www.tandfonline.com/doi/abs/10.1080/15567265.2013.776150