Thermal Characterization of Passive Cooling Techniques for High-Power Component Clusters
0
Citation
4
Reference
10
Related Paper
Abstract:
One of the most significant reasons for thermal defects in electronic systems is having high temperature areas on an electronic printed circuit board caused by multiple heat sources placed in a cluster. The current research focuses on characterizing thermally two possibilities of cooling such areas, one by employing individual heat sinks for each component in the cluster and another with having one heat sink to dissipate the temperature from all components at once. It has been shown that using individual heat sinks for each component has a significant impact on the overall temperature of the system, reducing the temperature with approximately 20 °C, in steady-state conditions. Individual heat sinks can be integrated in all electronic systems where high-power component clusters are used.Keywords:
Electronic component
Component (thermodynamics)
High heat
Sink (geography)
Passive cooling
Reduction of thermal resistance of naturally-cooled cooling system has been investigated. Pin-fin type heat sink was utilized as to clarify the effect of pin arrangement on the thermal performance of heat sink. The pitch of fins was set 1, 2, 3, 4, 5mm where the surface area of all heat sink was set as the same. The results show that the thermal resistance of heat sink decreases with increasing pitch of fin arrangement from 1 to 4mm, whereas the thermal resistance gets increase when the pitch was set 5mm. The results also show that even the slight decrease in fin efficiency causes the increase in the thermal resistance.
Fin
Sink (geography)
Cite
Citations (0)
Heat sinks are a critical component in numerous thermal management strategies, ranging from consumer electronics to data centers. The ability to perform an accurate thermal performance analysis of a heat sink is a crucial step in the design process. In situations where the heat sink is larger in area than the component it is being used to cool, a phenomena known as thermal spreading resistance takes effect. Thermal spreading resistance is not as easily calculated as other components of the thermal resistance of a heat sink (i.e. material and external thermal resistance). However, multiple solutions have been proposed and published that can be used to calculate thermal spreading resistance. The difficulty lies in that most of these solutions contain a very complex set of equations and are not very practical for use by the industry. As a result, the present research is aimed at developing a simple equation that can be used to calculate the thermal spreading resistance of a heat sink based on certain geometric and thermal characteristics.
Sink (geography)
Thermal reservoir
Cite
Citations (0)
The ongoing development of faster and smaller electronic components has led to a need for new technologies to effectively dissipate waste thermal energy. The pulsating heat pipe (PHP) shows potential to meet this need, due to its high heat flux capacity, simplicity, and low cost. A 20-turn flat plate PHP was integrated into an aluminum flat plate heat sink with a simulated electronic load. The PHP heat sink used water as the working fluid and had 20 parallel channels with dimensions 2 mm × 2 mm × 119 mm. Experiments were run under various operating conditions, and thermal resistance of the PHP was calculated. The performance enhancement provided by the PHP was assessed by comparing the thermal resistance of the heat sink with no working fluid to that of it charged with water. Uncharged, the PHP was found to have a resistance of 1.97 K/W. Charged to a fill ratio of approximately 75% and oriented vertically, the PHP achieved a resistance of .49 K/W and .53 K/W when the condenser temperature was set to 20°C and 30°C, respectively. When the PHP was tilted to 45° above horizontal the PHP had a resistance of .76 K/W and .59 K/W when the condenser was set 20°C and 30°C, respectively. The PHP greatly improves the heat transfer properties of the heat sink compared to the aluminum plate alone. Additional considerations regarding flat plate PHP design are also presented.
Condenser (optics)
Sink (geography)
Cite
Citations (8)
This paper provided a new type vapor chamber coupled fin heat sink, which is applied to high power LED light source. It shows good performance for the heat dissipation of high power LED devices. To compare its performance, the same LED light source with only fin heat sink was also fabricated and tested. Experimental tests, numerical simulation and thermal resistance analysis were conducted on the two prototypes. The basic principle of vapor chamber, the experiment set-up and the detailed comparisons between the simulated results and the tests results were also presented in this paper. The results showed that the vapor chamber coupled fin heat sink could make the temperature of the fin base plate uniform, the thermal resistance of vapor chamber was as low as 0.05K/W. The fin heat sink assembled on vapor chamber demonstrated good heat removal capacity, indicating an overall thermal resistance of 0.654K/W at the ambient temperature of 27°C.
Fin
Sink (geography)
Cite
Citations (20)
Recently the heat generation rate of electronic devices continues to increase, reaching as high as 100 W for CPUs in desktop PCs. Since conventional cooling methods are coming close to performance limits due to the restriction as to the outer dimensions allowed for heatsinks, there is a need for new cooling methods focusing on high-heat generating devices —in excess of 100 W. Accordingly, we have investigated the applicability of a new heatpipe-based remote heatsink (HP-RHS), where heatsinks with a sufficient heat-dissipating area are installed in an open space, and the heat is transferred there using heatpipes. The experimental results show that, using an HP-RHS with a 120-mm square fan, a heat rate of up to some 150 W can be dissipated adequately while keeping the temperature difference between the CPU case and the ambient below 30°C. This paper describes the successful development of such a good heatsink, which is capable of cooling over-100W heat-generating devices offering practicality together with silent operation.
High heat
Passive cooling
Active cooling
Cite
Citations (2)
As socketable LED modules are being developed the need for thermal characterization of heat-sinks aimed at cooling such modules has also arisen. The natural approach from manufacturers is to apply the component level LED thermal testing standards to characterize complete LED module and heat-sink systems. In order to obtain the real thermal resistance of such a complete assembly needs the consideration of the radiant power of the LEDs when calculating the thermal resistance of the complete assembly. Also, the contribution of the LED module, the thermal interface between the module and the heat-sink and the thermal resistance of the heat-sink need to be separated. For the latter problem thermal transient measurements followed by structure function analysis is a solution. To eliminate the need for the measurement of radiant flux of the LED module we suggest building a thermal dummy of the module in question which mechanically is compatible with the module but the heat source is a conventional silicon device instead of LEDs. The paper provides details how such a thermal dummy was created and used in characterizing different heat-sinks aimed at a particular LED module family.
Thermal grease
Transient (computer programming)
LED lamp
Cite
Citations (4)
For thermal management, power electronic devices are typically mounted on a heat sink with a thermal interface material (TIM) between the device tab and heat sink for the purpose of electrical isolation. Different thermal interface materials are available. The device can be mounted on to the heat sink with a screw or a special mounting clamp. Over the thermal resistances of the device, interface material and heat sink, the contact thermal resistances are also significant, but are challenging to be quantified. This paper presents experimental studies to evaluate the thermal resistance between the device junction and the heat sink, considering different thermal interface materials and different clamps at different mounting torques of the fastening screw. The device power dissipation, on state resistance and heat sink temperature are measured. Since the junction temperature cannot be measured directly, a procedure to estimate the same based on measured on-state resistance is presented. The experimental arrangement and techniques are reported along with comparative results for different mounting arrangements.
Thermal grease
Cite
Citations (3)
Seamless advancements in the electronics industry lead to high heat fluxes from very limited thermal real estates. Use of natural convection air cooling is of interest to meet some of the low flux cooling needs, while active cooling techniques via liquid or forced convection are the methods of choice. In natural convection heat transfer applications, the components used for cooling may represent a significant portion of the overall weight of the system. Consequently, advanced materials are of interest in such applications, as they may substantially reduce the total size and weight of the system. Many of these advanced materials have anisotropic thermophysical properties, hence the control of thermal conductivity is crucial. This paper is motivated to address the lack of understanding of the use of anisotropic advanced materials in natural convection environments. Numerical simulations are carried out to test the performance of heat sinks made of such materials and comparisons are made with the heat sinks of traditional engineering materials under the same conditions. The results demonstrate that the total weight of the system may be reduced drastically with the use of advanced materials relative to the most commonly used heat sink materials at the same thermal performance. A figure of merit (FOM) is proposed to compare the thermal performance of different heat sinks. Total resistance, conduction and convection resistances, and performance-related FOM values for each heat sink are presented. It is shown that the conduction thermal resistance is dominant at lower fin thicknesses for sparse heat sinks while it is negligible for dense heat sinks. Pyrolytic graphite-based heat sinks demonstrate the best thermal performance, while carbon-foam heat sinks produce the highest FOM values due to the material's low density.
Passive cooling
Fin
Computer cooling
Active cooling
Electronics cooling
Cite
Citations (21)
Cite
Citations (0)
This paper describes the results of a computational investigation of the thermal performance of chip scale package arrays with various low profile heat sinks. The arrays considered were fully populated with both modules and heat sinks. The heat sinks used in any single array were identical. The parameters evaluated included module spacing, cooling air inlet velocity, per module power dissipation, and heat sink design. The heat sinks fell into two categories: the plate and the block. A plate was defined as a single continuous piece of material covering all of the modules in the array. The block heat sinks were individual pieces of material that were affixed to each module and were not physically connected to the other heat sinks in the array. The results of this study are presented as thermal resistances for each module in the array. Also considered, for some specific cases, are the heat transfer coefficients for each heat sink as a function of its position within the array. Interesting results included the changing of the shape of the resistance curve with changes in heat sink design. Also noted was the relationship between the thermal resistance of a module and the heat transfer coefficient for the top surface of that heat sink. Related to this were the changes in thermal resistance due to changes in the material properties used in the modules and how this affected the heat flow within the array.
Thermal grease
Cite
Citations (2)