Analysis and optimization of activated carbon coated heat sinks

With the enhancements in nanotechnology, electronic devices shrank in size which led to a necessity to develop efficient thermal management strategies. These small electronic devices could be thermally managed through passive systems provided that effective materials are developed. Here, we use a layer of activated carbon on top of anodized aluminum heat sinks to utilize the sorption cycle of atmospheric water to create a desorption induced evaporative cooling effect. The material properties of the activated carbon lead to enhanced cooling by radiation and desorption, while the geometry of the heat sinks ensure surface area maximization. We develop a numerical simulation platform to determine the optimum geometry and the optimal activated carbon coating mass. Our results show that as the fin diameter and spacing shrink, and as the activated carbon mass increases within the considered range (0-100 mg), effective cooling of the chip could be achieved. We further employ our simulations to decouple the effects of desorption, radiation, and convection. Our analyses reveal that desorption only plays a vital role during the initial periods of operation, while cooling due to radiation and convection leads to an approximate to 20% increase in the overall steady-state heat transfer coefficient. This study goes beyond introducing a passive thermal management strategy for small electronic chips by providing a link between mass diffusion and thermal processes for effective transient operation of thermal devices.


Adsorption properties of boron nitride nanotubes
Khan, Saeed Ahmad; Sezgi, Naime Aslı; Balcı, Fatma Suna; Department of Chemical Engineering (2016)
The developments in nanotechnology in last decades have provided use of nanoparticles for many applications in various areas such as electronics, fuel cells, composites, cosmetics, and biomedical. They have excellent mechanical, thermal, and electrical properties. Nanotechnology is one of the fastest growing areas in materials and engineering science and biotechnology. Nanotubes have been one of the most regarded and studied type of nanoparticles up to now. Boron nitride nanotubes (BNNTs) are an important m...
Investigation of secondary cooling design enhancements in thermally limited compact notebooks
Khan, Muhammad Azhar Ali; Uzgoren, Eray; Muhtaroglu, Ali (2017-01-01)
Thermal design enhancements in a thermally limited compact notebook system are investigated in this paper. System temperature, power, and fan speed are characterized under a range of activity levels. A finite element model is developed, and validated against measurements. Design enhancements improve cooling with minimum intrusion to the existing mechanical design. A passive secondary heat pipe in the system reduces the CPU temperature by 5 degrees C, and improves the system performance through increased CPU...
Comparison of Intelligent Classification Techniques by Practicing a Specific Technology Audit
Berkol, A.; Kara, G.; Turk, A. (2016-09-08)
Technology audit activities arc carried out for assessment of firms' technological requirements, capacity or management capability. The aim of these assessments is to define the weaknesses of firms and develop actions in order to improve firms' technological capacity and/or technology management capability. Generally these activities are implemented with survey questionnaires. These questionnaires can be filled by managers of firms or can be implemented as an interview by independent experts. However, evalu...
Fabrication and investigation of extremely thin CdTe absorber layer solar cells
Hosseini, Arezoo; Erçelebi, Ayşe Çiğdem; Turan, Raşit; Department of Physics (2016)
Extremely thin absorber layer (ETA) solar cells aim to combine the advantages of using very thin and cheaply produced absorber layer on nano structured substrates with stability of all-solid-state solar cells. This type of photovoltaic devices use a nano structured interpenetrating heterojunction of thin light-absorbing layer at the interface between an n- and p-type semiconductors. N-type nano structured TiO2 layer is deposited on a Transparent Conducting Oxide coated glass (TCO) substrate, following with ...
Modeling effects of material properties and composition on ultrasound propagation
Özkök, Okan; Uludağ, Yusuf; Department of Chemical Engineering (2017)
Ultrasonic methods for material characterization have increasingly been used for the last decades thanks to advances in electronics and digital technologies since conventional methods accommodate several disadvantages like being time consuming. Advanced technology has brought highly accurate measurements with reasonable confidence level, and flexible ultrasonic testing parameters. The aim of this work is to carry out material characterization by combining modeling study and outputs of the ultrasonic device....
Citation Formats
A. A. Günay, “Analysis and optimization of activated carbon coated heat sinks,” ISI BILIMI VE TEKNIGI DERGISI-JOURNAL OF THERMAL SCIENCE AND TECHNOLOGY, vol. 42, no. 1, pp. 65–74, 2022, Accessed: 00, 2022. [Online]. Available: