Fluid flow and heat transfer of liquid-liquid two phase flow in microchannels: A review Ayoub Abdollahi a, ⁎, Rajnish N. Sharma a , Ashkan Vatani b a Department of Mechanical Engineering, University of Auckland, 20 Symonds Street, Auckland, 1010, New Zealand b School of Engineering, Griffith University, Gold Coast Campus, Queensland 4222, Australia abstract article info Available online xxxx The fluid flow and heat transfer behavior of liquid–liquid two phase flows have led to significantly improve the heat transfer rates in microchannels. Both numerical and experimental studies are reviewed in this paper to gain useful insights into the effect of a number of parameters such as film thickness, Peclet number, working fluid and flow geometry on hydrodynamic and thermal behavior of microchannels using liquid-liquid two phase flow. In addition, the paper summarises information about common correlations proposed to predict the pressure drop and heat transfer coefficient in the form of Nusselt number (Nu). The present study shows that there is little agreement across the literature between measured pressure drop and Nusselt number and predictions based on these correlations. Finally, the conclusions and important summaries, and some possible future development of this field are presented. © 2017 Elsevier Ltd. All rights reserved. Keywords: Liquid-liquid Tow-phase flow Heat transfer enhancement Microchannel Slug flow Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 2. Dimensionless parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 3. Pressure drop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 4. Heat transfer of liquid-liquid two phase flow. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 4.1. Numerical investigations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 4.2. Experimental investigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 4.3. Film thickness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 4.4. Effect of Peclet number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 4.5. Potential working fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 4.6. Flow geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 5. Conclusion and prospective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 1. Introduction Dissipating high amount of heat flux is an important issue of modern thermal management with the ever increasing demands for high per- formance and miniaturisation [2]. According to the literature [3] tradi- tional electronic cooling systems are no longer efficient enough to meet the needs of the developed high circuitry systems. Therefore a great deal of recent research has been dedicated to improve the microchannel heat sinks (MCHS) as an effective device for heat removal from microelectronic systems. The concept of MCHS heat sinks is defined as small mass and volume devices with higher convective heat transfer coefficients and large sur- face area to volume ratio. It was first proposed by Tuckerman and Pease [4] in 1981. By using MCHS the heat transfer coefficient could be en- hanced by periodic interruption of the thermal boundary layer, better flow mixing and increasing turbulence rate by generating secondary flow. The magnitude of generated heat flux in computer technology is projected to increase from 300 W/cm 2 to 500 W/cm 2 and 1000 W/cm 2 International Communications in Heat and Mass Transfer 84 (2017) 66–74 ⁎ Corresponding author. E-mail address: Ayoubabdollahi@gmail.com (A. Abdollahi). http://dx.doi.org/10.1016/j.icheatmasstransfer.2017.03.010 0735-1933/© 2017 Elsevier Ltd. All rights reserved. Contents lists available at ScienceDirect International Communications in Heat and Mass Transfer journal homepage: www.elsevier.com/locate/ichmt