0
Research Papers

Flow and Heat Transfer Analysis of an Electro-Osmotic Flow Micropump for Chip Cooling

[+] Author and Article Information
K. Pramod

Department of Mechanical Engineering,
Indian Institute of Technology Madras,
Chennai 600036, India

A. K. Sen

Department of Mechanical Engineering,
Indian Institute of Technology Madras,
Chennai 600036, India
e-mail: ashis@iitm.ac.in

1Corresponding author.

Contributed by the Electronic and Photonic Packaging Division of ASME for publication in the JOURNAL OF ELECTRONIC PACKAGING. Manuscript received December 23, 2013; final manuscript received May 9, 2014; published online June 5, 2014. Assoc. Editor: Pradip Dutta.

J. Electron. Packag 136(3), 031012 (Jun 05, 2014) (14 pages) Paper No: EP-13-1137; doi: 10.1115/1.4027657 History: Received December 23, 2013; Revised May 09, 2014

This paper reports theoretical and numerical analysis of fluid flow and heat transfer in a cascade electro-osmotic flow (EOF) micropump for chip cooling. A simple analytical model is developed to determine the temperature distribution in a two-dimensional (2D) single channel EOF micropump with forced convection due to a voltage difference between both ends. Numerical simulations are performed to determine the temperature distribution in the domain which is compared with that predicted by the model. A novel cascade EOF micropump with multiple microchannels in series and parallel and with an array of interdigitated electrodes along the flow direction is proposed. The simulations predict the maximum flow rate and pressure capability of one single stage of the micropump and the analytical model employs equivalent circuit theory to predict the total flow rate and back pressure. Each stage of the proposed micropump comprises sump and pump regions having opposing electric field directions. The various design parameters of the micropump includes the height of the pump and sump (h), number of stages (n), channel width (w), thickness of the channel wall or fin (r), and width ratio of the pump and sump (s:p) regions. Numerical simulations are performed to predict the effects of these design parameters on the pump performance which is compared with that predicted by the analytical model. The micropump is used for cooling cooling of an Intel® CoreTM i5 chip which produces a maximum heat of 95 W over an area of 3.75 × 3.75 cm. Based on the parametric studies a design for the cascade EOF micropump is proposed which provides a maximum flow rate of 14.16 ml/min and a maximum back pressure of 572.5 Pa to maintain a maximum chip temperature of 310.63 K.

Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Velocity profile v and the negative Debye layer charge density profile ρeq in an ideal EOF

Grahic Jump Location
Fig. 2

EOF between two infinite parallel plates for forced convection

Grahic Jump Location
Fig. 3

Energy conservation for an element of length dx

Grahic Jump Location
Fig. 4

Expected temperature profile along x- and y-directions

Grahic Jump Location
Fig. 5

Planar layout of the proposed 3D cascade EOF micropump

Grahic Jump Location
Fig. 6

Schematic of a single stage of the cascade EOF micropump showing the design parameters

Grahic Jump Location
Fig. 7

Section of a cascade EOF micropump with a single channel and single stage

Grahic Jump Location
Fig. 8

The equivalent circuit model for calculating the total back pressure and flow rate

Grahic Jump Location
Fig. 9

Variation of the temperature of bottom plate along x-direction

Grahic Jump Location
Fig. 10

Variation of the temperature of fluid along y-direction (at x = 0.5 cm)

Grahic Jump Location
Fig. 11

(a) Geometry of the heat transfer in EOF through parallel microchannels separated by channel walls (fins) and (b) surface plot of temperature plot across x–y plane

Grahic Jump Location
Fig. 12

Variation of the temperature at the bottom wall along the flow direction at the center of the channel, i.e., y = 50 μm

Grahic Jump Location
Fig. 13

Variation of the temperature along z-direction at the center of the channel, i.e., y = 50 μm and x = 0.5 cm

Grahic Jump Location
Fig. 14

Surface plot of temperature on y–z plane

Grahic Jump Location
Fig. 15

Variation of temperature in the y-direction at x = 0.5 cm and for different values of z

Grahic Jump Location
Fig. 16

Conceptual model of a section of the 3D cascade EOF micropump used for simulation

Grahic Jump Location
Fig. 17

Surface plot of (a) temperature on x–z plane and (b) temperature on y–z plane, x = 1500 mm

Grahic Jump Location
Fig. 18

Pressure-flow (P-Q) characteristics of 3D cascade EOF micropump per stage per channel

Grahic Jump Location
Fig. 19

Velocity profile in the sump and pump regions

Grahic Jump Location
Fig. 20

(a) Variation of flow rate Q and back pressure ΔP and (b) temperature Tmax with number of stages n

Grahic Jump Location
Fig. 21

(a) Variation of flow rate Q and back pressure ΔP and (b) temperature Tmax with sump-to-pump (s:p) width ratio

Grahic Jump Location
Fig. 22

(a) Variation of flow rate Q and back pressure ΔP and (b) temperature Tmax with wall-to-channel (r:w) width ratio

Grahic Jump Location
Fig. 23

(a) Variation of flow rate Q and back pressure ΔP and (b) temperature Tmax with channel aspect ratio (fixed h)

Grahic Jump Location
Fig. 24

(a) Variation of flow rate Q and back pressure ΔP and (b) temperature Tmax with channel aspect ratio (fixed w)

Grahic Jump Location
Fig. 25

Sketch of the top and bottom layers of the proposed device, the electrode patterns and access hole on the top layer, and the etched fluidic channels and posts/fins are shown

Grahic Jump Location
Fig. 26

Schematic of the process flow for fabrication of the device

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In