Effects of passage divider and packed brass beads on heat transfer characteristic of the pin-fin heat sink by water cooling

2019 ◽  
Vol 56 (5) ◽  
pp. 1429-1441
Author(s):  
Tzer-Ming Jeng ◽  
Sheng-Chung Tzeng ◽  
Ching-Wen Tseng ◽  
Chia-Hung Chang
2018 ◽  
Vol 7 (3.14) ◽  
pp. 1
Author(s):  
Wei Long Yeo ◽  
Kim Ho Yeap ◽  
Koon Chun Lai ◽  
Pei Song Chee ◽  
Kok Seng Ong

In the present study, the fluid flow and heat transfer characteristic of microchannel heat sink with microfins are studied numerically at Reynold number ranging from 400 to 1200. The influence of microfins on the Nusselt number and pressure drop are investigated. Five different types of microfins namely cylindrical microfins (Case A), diverge cylindrical microfins (Case B), diverge cylindrical microfins with semi-circle rib (Case C), diverge cylindrical microfins with rectangular rib (Case D) and diverge cylindrical microfins with triangular rib (Case E) are designed. A comparative analysis of these five types of microfins with bare microchannel has been conducted. The result highlighted the extended microfins augmented the heat transfer characteristic by disrupt the thermal boundary layer. The overall thermal performances of microchannel heat sink with microfins are 1.1 – 1.47 times higher compared to bare microchannel.  


2021 ◽  
Vol 170 ◽  
pp. 107109
Author(s):  
Mohanad A. Alfellag ◽  
Hamdi E. Ahmed ◽  
Mohammed Gh. Jehad ◽  
Marwan Hameed

2011 ◽  
Vol 115 (1164) ◽  
pp. 83-90 ◽  
Author(s):  
W. Bao ◽  
J. Qin ◽  
W. X. Zhou

Abstract A re-cooled cycle has been proposed for a regeneratively cooled scramjet to reduce the hydrogen fuel flow for cooling. Upon the completion of the first cooling, fuel can be used for secondary cooling by transferring the enthalpy from fuel to work. Fuel heat sink (cooling capacity) is thus repeatedly used and fuel heat sink is indirectly increased. Instead of carrying excess fuel for cooling or seeking for any new coolant, the cooling fuel flow is reduced, and fuel onboard is adequate to satisfy the cooling requirement for the whole hypersonic vehicle. A performance model considering flow and heat transfer is build. A model sensitivity study of inlet temperature and pressure reveals that, for given exterior heating condition and cooling panel size, fuel heat sink can be obviously increased at moderate inlet temperature and pressure. Simultaneously the low-temperature heat transfer deterioration and Mach number constrains can also be avoided.


Author(s):  
D. Sahray ◽  
H. Shmueli ◽  
N. Segal ◽  
G. Ziskind ◽  
R. Letan

In the present work, horizontal-base pin fin heat sinks exposed to free convection in air are studied. They are made of aluminum, and there is no contact resistance between the base and the fins. For the same base dimensions the fin height and pitch vary. The fins have a constant square cross-section. The edges of the sink are blocked: the surrounding insulation is flush with the fin tips. The effect of fin height and pitch on the performance of the sink is studied experimentally and numerically. In the experiments, the heat sinks are heated using foil electrical heaters. The heat input is set, and temperatures of the base and fins are measured. In the corresponding numerical study, the sinks and their environment are modeled using the Fluent 6 software. The results show that heat transfer enhancement due to the fins is not monotonic. The differences between sparsely and densely populated sinks are analyzed for various fin heights. Also assessed are effects of the blocked edges as compared to the previously studied cases where the sink edges were exposed to the surroundings.


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