Numerical survey on performance of hybrid NePCM for cooling of electronics: Effect of heat source position and heat sink inclination

2020 ◽  
pp. 1-30
Author(s):  
Hamza Faraji ◽  
Mustapha El Alami ◽  
Adeel Arshad ◽  
Yassine Hariti
Keyword(s):  
Heat Source ◽  
Phase Change ◽  
Heat Sink ◽  
Simple Algorithm ◽  
Electronic Component ◽  
Al2o3 Nanoparticles ◽  
Volume Method ◽  
Velocity Pressure ◽  
Cooling Of Electronics

Abstract This paper reports on numerical simulations of passive cooling of an electronic component. The strategy is based on the fusion of a nano-enhanced phase change material (NePCM) by insertion of hybrid Cu-Al2O3 nanoparticles. This study analyses the combined effects of the position of the electronic component and the inclination of the heat sink for rectangular and square geometries on the heat transfer and flow structure of liquid NePCM. The heat sink is heated by a protuberant heat source simulating the role of an electronic component generating a volumetric power. The electronic component is mounted on a substrate modelling the role of a motherboard. All the walls of the heat sink are adiabatic. The development of a 2D mathematical model is based on the equations of conservation of mass, momentum and energy. This system of equations is solved using the finite volume method and the SIMPLE algorithm for velocity-pressure coupling. The enthalpy-porosity approach is adopted to model the phase change. The results obtained show that the position of the electronic component and the inclination of the enclosure have important effects on the efficiency of the cooling strategy. The inclination of 900 and the position of d=0.5 represent the case where the cooling of the electronic component is guaranteed and operates safely with a minimum temperature difference recorded along it. The electronic component is well cooled in a rectangular heat sink than in a square one.

Numerical Survey of the Melting Driven Natural Convection Using Generation Heat Source: Application to the Passive Cooling of Electronics Using Nano-Enhanced Phase Change Material

2019 ◽  
Vol 12 (2) ◽  
Author(s):  
Hamza Faraji ◽  
Mustapha Faraji ◽  
Mustapha El Alami
Keyword(s):  
Heat Transfer ◽  
Natural Convection ◽  
Heat Source ◽  
Phase Change ◽  
Phase Change Material ◽  
Metallic Nanoparticles ◽  
Simple Algorithm ◽  
Bottom Side ◽  
Volume Method ◽  
Change Material

Abstract The present paper reports numerical results of the melting driven natural convection in an inclined rectangular enclosure filled with nano-enhanced phase change material (NePCM). The enclosure is heated from the bottom side by a flush-mounted heat source (microprocessor) that generates heat at a constant and uniform volumetric rate and mounted on a substrate (motherboard). All the walls are considered adiabatic. The purpose of the investigation is analyzing the effect of nanoparticles insertion by quantifying their contribution to the overall heat transfer. Combined effects of the PCM type, the inclination angle and the nanoparticles fraction on the structure of the fluid flow and heat transfer are investigated. A 2D mathematical model based on the conservation equations of mass, momentum, and energy was developed. The governing equations were integrated and discretized using the finite volume method. The SIMPLE algorithm was adopted for velocity–pressure coupling. The obtained results show that the nanoparticles insertion has an important quantitative effect on the overall heat transfer. The insertion of metallic nanoparticles with different concentrations affects the thermal behavior of the heat sink. They contribute to an efficient cooling of the heat source. The effect of nanoparticles insertion is also shown at the temperature distribution along the substrate.

scholarly journals Numerical study of the thermal and hydraulic performances of heat sink made of wavy fins

2019 ◽  
Vol 23 (1) ◽  
pp. 150-161
Author(s):  
R. Bouchenafa ◽  
Hussein A. Mohammed ◽  
R. Saim
Keyword(s):  
Heat Sink ◽  
Transfer Rate ◽  
Numerical Study ◽  
Simple Algorithm ◽  
Equation Model ◽  
Heat Sinks ◽  
Governing Equations ◽  
Wave Numbers ◽  
Volume Method ◽  
Velocity Pressure

Abstract The aim of this paper is to numerically investigate the thermal and hydraulic performances of the two heat sinks made of wavy fins (WFHS). The governing equations fitted with boundary conditions were solved using the finite volume method, and the SIMPLE algorithm for the coupling velocity-pressure. The two-equation model k-ϵ was used to describe the turbulence phenomenon. The effects of wave numbers and the amplitude of wavy fins heat sink on the thermal and flow fields are studied and compared with the plate fin heat sink (PFHS). The results show that the use of wavy fins improves significantly the heat transfer rate, accompanied by a pressure drop penalty.

Numerical Analysis of a Hybrid Heat Sink Using Phase Change Material: Application to Cooling of Electronic Components

2008 ◽  
Author(s):  
Mustapha Faraji ◽  
Hamid El Qarnia
Keyword(s):  
Phase Change ◽  
Phase Change Material ◽  
Thermal Performance ◽  
Heat Sink ◽  
Energy Transport ◽  
Electronic Component ◽  
Volume Control ◽  
Algebraic Equations ◽  
Control Approach ◽  
Change Material

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-ecosane 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 (2D) 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 discretised by using the volume control approach. The resulting algebraic equations were next solved iteratively by using TDMA algorithm. Numerical investigations were conducted in order to optimize the thermal performance of the heat sink. The optimization involves determination of the key parameters of the heat sink that maximize the time required by the base of the electronic component to reach a critical temperature.

Small-Scale Thermal Energy Storage With Capillary Conductivity Enhancement

2016 ◽  
Author(s):  
A. Hays ◽  
E. Borquist ◽  
D. Bailey ◽  
D. Wood ◽  
L. Weiss
Keyword(s):  
Energy Storage ◽  
Heat Source ◽  
Phase Change ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Heat Sink ◽  
Large Scale ◽  
Heat Pipes ◽  
Small Scale ◽  
Conductivity Enhancement

Thermal energy is a leading topic of discussion in energy conservation and environmental fields. Specifically for large-scale applications solar energy and concentrated solar power (CSP) systems use techniques that include thermal energy storage systems and phase change materials to harvest energy. However, on the smaller centimeter scale, there have been historically fewer investigations of these same techniques. The main goal of this paper is to investigate thermal energy storage (TES) as applied to a small scale system for thermal energy capture. Typical large-scale TES consists of a phase change material that usually employs a wax or oil medium held within a conductive container. The system stores the energy when the wax medium undergoes a phase change. In typical applications like buildings, the system absorbs and stores incoming thermal energy during the day, and releases it back to the surrounding environment as temperatures cool at night. This paper presents a new TES unit designed to integrate with a thermoelectric for energy harvesting application in small, cm-scale applications. In this manner, the TES serves as a thermal battery and source for the thermoelectric, even when originating power supply is interrupted. A unique feature of this TES is the inclusion of internal heat pipes. These heat pipes are fabricated from copper tubing and filled with working fluid, mounted vertically, and immersed in the wax medium of the TES. This transfers heat to the wax by means of thermal conductivity enhancement as an element of the heat pipe operation. This represents a first of its kind in this small-scale, thermal harvesting application. As tested, the TES rests atop a low temperature (60 °C) heat source with a heat sink as the final setup component. The heat sink serves to simulate thermal energy rejection to a future thermoelectric device. To measure the temperature change of the device, thermocouples are placed on either side of the TES, and a third placed on the heat source to ensure that the energy input is appropriate and constant. Heat flux sensors (HFS) are placed between the heat source and the TES and between the TES and heat sink to monitor heat transferred to and from the device. The TES is tested in a variety constructions as part of this effort. Basic design of the storage volume as well as fluid fill levels within the heat pipes are considered. Varying thermal energy inputs are also studied. Temperature and heat flux data are compared to show the thermal absorption capability and operating average thermal conductivities of the TES units. The baseline average thermal conductivity of the TES is approximately 0.5 W/mK. This represents the TES with wax alone filling the internal volume. Results indicate a fully functional, heat pipe TES capable of 8.23 W/mK.

Effect of position and height of a shield on convective heat transfer performances of plate fin heat sink

2015 ◽  
Vol 25 (5) ◽  
pp. 1047-1063 ◽  
Author(s):  
Rachid Bouchenafa ◽  
Rachid Saim ◽  
Said Abboudi ◽  
Hakan F. Öztop
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Heat Sink ◽  
Dynamic Performance ◽  
Simple Algorithm ◽  
Governing Equations ◽  
Enhancement Of Heat Transfer ◽  
Content Type ◽  
The One ◽  
Volume Method

Purpose – The purpose of this paper is to examine the thermal and dynamic performance of the plate-fin heat sink fitted with a shield in the bypass. Design/methodology/approach – The governing equations were solved using the finite volume method based on the SIMPLE algorithm. The k-ω Shear Stress Transport was used to model turbulence. The thermal and dynamic results were presented in term of average Nusselt number and friction factor, respectively. The effect of the height (Hs=6, 10 and 13) and the position (X=0, 1/3, 1/2, 2/3 and 3/4) of the shield was studied for a Reynolds number ranging from 2×103 to 12×103 and compared with a heat sink without shield. To evaluate the performance of different heat sink geometries, the efficiency was presented and discussed. Findings – By adding a shield in the bypass, a greater amount of air is injected between the heat sink fins, which improves the heat transfer (advantage) of the one part, and increases the friction on the other hand (disadvantage). The efficiency of the heat sink varies inversely proportional with the Reynolds number. Originality/value – The originality of this work is the method for enhancement of heat transfer.

The effect of an aluminum heat-sink layer on the laser-induced amorphization of SiOx/TeGeSn/SiOx phase-change recording films

1989 ◽  
Vol 47 ◽  
pp. 574-575
Author(s):  
Matthew R. Libera ◽  
Martin Chen
Keyword(s):  
Thin Film ◽  
Phase Change ◽  
Heat Sink ◽  
Multilayer Film ◽  
Glassy Phase ◽  
Film Structure ◽  
Glass Forming ◽  
Active Storage ◽  
Dielectric Layers ◽  
Amorphous States

Phase-change erasable optical storage is based on the ability to switch a micron-sized region of a thin film between the crystalline and amorphous states using a diffraction-limited laser as a heat source. A bit of information can be represented as an amorphous spot on a crystalline background, and the two states can be optically identified by their different reflectivities. In a typical multilayer thin-film structure the active (storage) layer is sandwiched between one or more dielectric layers. The dielectric layers provide physical containment and act as a heat sink. A viable phase-change medium must be able to quench to the glassy phase after melting, and this requires proper tailoring of the thermal properties of the multilayer film. The present research studies one particular multilayer structure and shows the effect of an additional aluminum layer on the glass-forming ability.

Sign in / Sign up

Export Citation Format

Share Document