Please use this identifier to cite or link to this item: https://doi.org/10.1016/j.ijheatmasstransfer.2012.11.020
Title: A comparative study of flow boiling heat transfer and pressure drop characteristics in microgap and microchannel heat sink and an evaluation of microgap heat sink for hotspot mitigation
Authors: Alam, T.
Lee, P.S. 
Yap, C.R. 
Jin, L.
Keywords: Flow visualization
Local hotspot
Microchannel heat sink
Microgap heat sink
Pressure instability
Issue Date: 2013
Citation: Alam, T., Lee, P.S., Yap, C.R., Jin, L. (2013). A comparative study of flow boiling heat transfer and pressure drop characteristics in microgap and microchannel heat sink and an evaluation of microgap heat sink for hotspot mitigation. International Journal of Heat and Mass Transfer 58 (1-2) : 335-347. ScholarBank@NUS Repository. https://doi.org/10.1016/j.ijheatmasstransfer.2012.11.020
Abstract: Two phase microgap heat sink has a large potential to minimize the drawbacks associated with two phase microchannel heat sink, especially flow instabilities, flow reversal and lateral variation of flow and wall temperature between channels. This new concept of the two-phase microgap heat sink is very promising due to its high heat transfer rate and ease of fabrication. However, comparison of the performance of microgap heat sink (heat transfer, pressure drop and instability characteristics) with some conventional heat sink has not been investigated extensively. In this study, experiments have been conducted to investigate the heat transfer and pressure drop characteristics of deionized water (DI) in microgap heat sink and compare these experimental results with similar data obtained for microchannel heat sink. These studies are carried out with the inlet DI water temperatures 86 °C at different mass fluxes ranging from 400 to 1000 kg/m2 s, for effective heat flux 0-85 W/cm 2. High speed flow visualizations are conducted simultaneously along with experiments to illustrate the bubble characteristics in the microchannel and microgap heat sink. Experimental result shows that microgap heat sink performs better at high heat flux and low mass flux due to confined slug and annular boiling dominance and consequent delay of dryout phase. So, this microgap technology is promising and an effective method to dissipate very high heat fluxes in compact space with a smaller rate of coolant flow. Moreover, pressure drop is higher in microchannel than microgap heat sink at all the heat fluxes. In addition, encouraging results have been obtained using microgap as it can potentially mitigate local hotspot, reduce flow instabilities, flow reversal and maintain uniform wall temperatures over the heated surface. © 2012 Elsevier Ltd. All rights reserved.
Source Title: International Journal of Heat and Mass Transfer
URI: http://scholarbank.nus.edu.sg/handle/10635/84771
ISSN: 00179310
DOI: 10.1016/j.ijheatmasstransfer.2012.11.020
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

SCOPUSTM   
Citations

30
checked on May 20, 2018

WEB OF SCIENCETM
Citations

22
checked on Apr 23, 2018

Page view(s)

46
checked on May 11, 2018

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.