Electronic component cooling enhancement using nanofluids in a radial flow cooling system

For 300 MW inner cooling turbo generator, a discrete model for cooling material flow distribution of radial ventilation cooling system has been developed. The structure optimization is studied with this model. The effect of the radial distance and the tangential distance on stator’s radial flow distribution was analyzed and optimized. The results of the simulation show that with the same inlet-outlet flow pressure the flow deviation increased as the radial distance increased but the tangential distance decreased oppositely.

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Passive Cooling of Protruding Electronic Components by Latent Heat of Fusion Storage

Journal of Electronic Packaging ◽

10.1115/1.3103953 ◽

2009 ◽

Vol 131 (2) ◽

Cited By ~ 6

Author(s):

Mustapha Faraji ◽

Hamid El Qarnia

Keyword(s):

Heat Sink ◽

Cooling System ◽

Heat Removal ◽

Electronic Component ◽

Heat Of Fusion ◽

Volume Control ◽

Maximum Temperature ◽

Algebraic Equations ◽

Electronic Components ◽

Control Approach

The aim of the present work is to study the thermal performance of a hybrid heat sink used for cooling management of protruding substrate-mounted electronic chips. The power generated in electronic chips is dissipated in phase change material (PCM) (n-eicosane with melting temperature Tm=36°C) that filled a rectangular enclosure. The advantage of using this cooling strategy is that the PCMs are able to absorb a high amount of heat generated by electronic component (EC) without acting the fan, during the charging process (melting of the PCM). A two-dimensional mathematical model was developed in order to analyze and optimize a heat sink. The governing equations for masse, momentum, and energy transport were developed and discretized by using the volume control approach. The resulting algebraic equations were next solved iteratively by using tri diagonal matrix algorithm. A series of numerical investigations were conducted in order to examine the effects of the heat generation based Rayleigh number, Ra, and the position of the bottom electronic component, Lh, on the thermal behavior of the proposed cooling system. Results are obtained for velocity and temperature distributions, maximum temperature heat sources, percentage contribution of plate (substrate) heat conduction on the heat removal from electronic components, temperature profile within finite conductive plate and local heat flux density at the plate—modules/PCM interface. The effect of these two key parameters on the electronic component working time (time required by electronic components to reach a critical temperature, Tcr) was analyzed.

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Numerical Evaluation on the Heat Dissipation Capability of Liquid Metal Based Chip Cooling Device

Electronic and Photonic Packaging, Electrical Systems Design and Photonics, and Nanotechnology ◽

10.1115/imece2005-80189 ◽

2005 ◽

Cited By ~ 4

Author(s):

Zhong-Shan Deng ◽

Jing Liu

Keyword(s):

Liquid Metal ◽

Thermal Management ◽

Heat Dissipation ◽

Cooling System ◽

Three Dimensional ◽

Heat Transfer Process ◽

Liquid Cooling ◽

Chip Cooling ◽

Cooling Enhancement ◽

Liquid Cooling System

With the sharp improvement in computational speed of CPU, thermal management becomes a major concern in the current microelectronic industry. Conventional thermal management methods for CPU chip cooling are approaching their limit for quite a few newly emerging high integrity and high power processors. Therefore, liquid metal based chip cooling method has been proposed to accommodate to this request. In order to better understand the mechanisms of the cooling enhancement by the liquid metal based cooling technique, the three-dimensional heat transfer process thus involved in the cooling chip is numerically simulated in this study. A series of calculations with different flow rates and thermal parameters are performed. The cooling capability of the liquid metal is also compared with that of the water-cooling system. The results indicate that the liquid metal has powerful cooling capability, which is much better than that of the conventional liquid-cooling system.

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A High Angle, Double Tilting Cold Stage for the AEI EM7

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052262 ◽

1974 ◽

Vol 32 ◽

pp. 450-451

Author(s):

P.R. Swann ◽

A.E. Lloyd

Keyword(s):

Habit Plane ◽

Temperature Control ◽

Tilt Angle ◽

Cooling System ◽

Thermal Drift ◽

High Angle ◽

Cold Stage ◽

High Degree ◽

Better Than

Figure 1 shows the design of a specimen stage used for the in situ observation of phase transformations in the temperature range between ambient and −160°C. The design has the following features a high degree of specimen stability during tilting linear tilt actuation about two orthogonal axes for accurate control of tilt angle read-out high angle tilt range for stereo work and habit plane determination simple, robust construction temperature control of better than ±0.5°C minimum thermal drift and transmission of vibration from the cooling system.

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A conduction-cooled stage for high-resolution Cryo-SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131048 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1282-1283

Author(s):

John G. Sheehan

Keyword(s):

High Resolution ◽

Liquid Nitrogen ◽

Mechanical Stability ◽

Cooling System ◽

Cold Trap ◽

Nitrogen Gas ◽

Particulate Suspensions ◽

Advantages And Disadvantages ◽

Convection Cooling ◽

Styrene Butadiene

The goal is to examine with high resolution cryo-SEM aqueous particulate suspensions used in coatings for printable paper. A metal-coating chamber for cryo-preparation of such suspensions was described previously. Here, a new conduction-cooling system for the stage and cold-trap in an SEM specimen chamber is described. Its advantages and disadvantages are compared to a convection-cooling system made by Hexland (model CT1000A) and its mechanical stability is demonstrated by examining a sample of styrene-butadiene latex.In recent high resolution cryo-SEM, some stages are cooled by conduction, others by convection. In the latter, heat is convected from the specimen stage by cold nitrogen gas from a liquid-nitrogen cooled evaporative heat exchanger. The advantage is the fast cooling: the Hexland CT1000A cools the stage from ambient temperature to 88 K in about 20 min. However it consumes huge amounts of liquid-nitrogen and nitrogen gas: about 1 ℓ/h of liquid-nitrogen and 400 gm/h of nitrogen gas. Its liquid-nitrogen vessel must be re-filled at least every 40 min.

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