Simulation and experimental investigation of pressure loss and heat transfer in microchannel networks containing bends and T-junctions

In this paper, the pressure loss and heat transfer in bending and branching microchannels for Re numbers ranging from 10 to 3000 are investigated. Redirecting and splitting the fluid leads to an enhanced heat transfer, but at the same time the pressure loss is increased. The shape of the investigated bends and branchings has a significant influence on both, pressure loss and heat transfer. Fluid flow and heat transfer are simulated for single elements like L-bends and T-joints with different shapes. Test structures are fabricated in silicon and experimentally investigated. The aim of this work is to get an impression of the physical behavior in small elements that enable the development of new liquid cooling systems with higher cooling ability and higher effectiveness.

[1]  H. Oertel,et al.  Prandtl - Führer durch die Strömungslehre , 2001 .

[2]  Satish G. Kandlikar,et al.  High Flux Heat Removal with Microchannels—A Roadmap of Challenges and Opportunities , 2005 .

[3]  Norbert Kockmann,et al.  Fluid Dynamics and Transfer Processes in Bended Microchannels , 2005 .

[4]  A. Bejan Constructal-theory network of conducting paths for cooling a heat generating volume , 1997 .

[5]  D. Pence,et al.  REDUCED PUMPING POWER AND WALL TEMPERATURE IN MICROCHANNEL HEAT SINKS WITH FRACTAL-LIKE BRANCHING CHANNEL NETWORKS , 2003 .

[6]  David F. Fletcher,et al.  Low-Reynolds number heat transfer enhancement in sinusoidal channels , 2007 .

[7]  P. Cheng,et al.  Heat transfer and pressure drop in fractal tree-like microchannel nets , 2002 .

[8]  P. Woias,et al.  Characterization of Laminar Transient Flow Regimes and Mixing in T-shaped Micromixers , 2009 .

[9]  Robert W Barber,et al.  Biomimetic design of microfluidic manifolds based on a generalised Murray's law. , 2006, Lab on a chip.

[10]  Optimierte Mikro-Kühlkanäle für thermisch hochbelastete Bauteile , 2006 .

[11]  Adrian Bejan,et al.  Constructal tree-shaped parallel flow heat exchangers , 2006 .

[12]  P. Woias,et al.  Convective mixing and chemical reactions in microchannels with high flow rates , 2006 .

[13]  A. Bejan Shape and Structure, from Engineering to Nature , 2000 .

[14]  D. Poulikakos,et al.  Laminar mixing, heat transfer and pressure drop in tree-like microchannel nets and their application for thermal management in polymer electrolyte fuel cells , 2004 .

[15]  Ian Papautsky,et al.  Effects of rectangular microchannel aspect ratio on laminar friction constant , 1999, MOEMS-MEMS.

[16]  M. Gad-el-Hak The MEMS Handbook , 2001 .

[17]  David F. Fletcher,et al.  Laminar Flow in a Periodic Serpentine Channel , 2006 .

[18]  P. Cheng,et al.  An experimental investigation on the thermal efficiency of fractal tree-like microchannel nets , 2005 .

[19]  Tianliang Yang,et al.  Multiplicity and stability of convection in curved ducts: Review and progress , 2004 .