A heat sink is a part that conducts heat from a heat generating component to a larger surface area to dissipate the heat to the surroundings thus reducing the temperature of the component. The protective case of the device containing the heat-generating component could theoretically function as a heat sink as well. The heat sink is a passive, single-piece component without moving parts, but choosing the right one in terms of function, performance, cost, and size requires consideration and study. When the computer starts, the processor starts working and in the process it creates heat to a very high level. Phase change material (PCM) heat sinks act as actual heat sinks and are particularly useful where there is a lack of heat exchange media. Simply put, a heat sink is an object that disperses heat from another object. The ATX 4 pin power supply connector is a standard motherboard power connector used to provide +12 VDC to the processor voltage regulator. Heat sink is a heat exchanger used to transfer heat generated by a mechanical or an electronic device to the surroundings. This can happen if the CPU is running at full capacity for an extended period of time or if the air surrounding the computer is simply too hot. If the heat sink is not cooled, it would eventually reach the temperature of the component to which it is attached. Anyone that has opened up an old computer has seen the large chunk of metal placed on a CPU, GPU, or other high-power IC. Traditional heat sinks used for cooling electronics are not exactly heat "sinks," but are rather heat exchangers. Thermal adhesive or thermal grease can improve the performance of the heat sink by filling the air gap between the heat sink and the heat spreader on the device. Heat pipes transport the heat generated by the chip, where it is dissipated to the environment with the aid of the ... friction factor for this mixture of flow is a function of friction The heat source is assumed to cover the entire base of the heat sink. HEAT SINK has a thermal conductor that carries heat away from the CPU into fins that provide a large surface area for the heat to dissipate throughout the rest of the computer, thus cooling both the heat sink and processor. The attachment method of the heat sink and the thermal interface material also affect the die temperature of the integrated circuit. This tool is designed to calculate junction temperature of an electronic device (typically power devices) given four parameters: the maximum ambient temperature, the device's junction-to-package thermal resistance, the thermal resistance of the heat sink… The value of the spreading resistance (R sp) is obtained from [2], Rsp stems from dissimilar contact areas between the source and the sink.That is when the heat sink is larger than the device, as shown in Figure 1. How does the Heat Sink Calculator Work? Wang, this model predicts heat transfer from natural convection horizontal annular heat sinks. Figure 2 shows the typical range of cost functions for different types of heat sinks in terms of required thermal resistance. However, most heat sinks use fins to increase surface area and create optimal air flow patterns, as shown in the table above. This makes the ground not only an excellent heat source in winter but also a good heat sink for cooling in summer. Lecture 19: Heat conduction with distributed sources/sinks (Compiled 2 November 2017) In this lecture we consider heat conduction problems in which there is a distributed source or sink function s(x;t) that applies throughout the domain. MOBO FUNCTION 1. For sufficient heat dissipation through the heat sink, heat must be able to travel from the device through a thermally conductive path to the heat sink. But sometimes the heat sink itself can become too hot. sink heat pipe assembly shown in Figure 1 is mounted on a slim cold plate. Heat sinks function by efficiently transferring thermal energy ("heat") from an object at high temperature to a second object at a lower temperature with a much greater heat capacity. 7 Conductance and heat transfer by the heat sink as a function of the number of fins 18 8 Temperature at the base of the heat sink for fin thickness of 0.0022441 in. Hence, it allows high performance heat sinks to be fabricated for applications. This rapid transfer of thermal energy quickly brings the first object into thermal equilibrium with the second, lowering the temperature of the first object, fulfilling the heat sink's role as a cooling device. Heat sinks function by efficiently transferring thermal energy "heat" from an object at a relatively high temperature to a second object at a lower temperature with a much greater heat capacity. Stamped heat sink geometries are designed for specific electronic package types to ensure optimized fit and function on a PCB. θ CS is a function of the TIM thermal conductivity, its thickness, and the area over which it is spread. A reference link has been placed below the calculator for further reading. A heat sink uses a liquid medium to absorb waste heat energy and move it away from the electronics, where it can then be safely dissipated into the environment. You can use a thermal paste, thermal grease, or another thermally conductive adhesive. If the device overheats, the performance can be impacted, or in worst cases it fails and can become a safety hazard. In computers, it is attached with a microprocessor chip to absorb heat and sends it to air. Electronics generate heat, and tightly stacked electronics or poorly ventilated electronics have the potential to generate enough heat to damage or inhibit the function of the devices. Nearly all computers have heat sinks , which help keep the CPU cool and prevent it from overheating. Heat sink definition is - a substance or device that absorbs or dissipates especially unwanted heat (as from a process or an electronic device). That’s the main function why a heat sink is installed over a processor. To aid the heat sink you may wish to draw hot air into the heat sink. Or, if the heat sink is of the same size as the source, but heat is not spread uniformly. Most modern power electronics devices require controlled temperature environments, in order for them to function correctly. A heat sink’s aspect ratio is the comparison between-The fin height; The distance between the fins; Heat sinks generally come in aspect ratios of 3:1 and 5:1. Furthermore, a two-channel function generator was used to excite The heat sink size calculator first calculates the optimum spacing between the fins to achieve maximum convection cooling. These heat sinks can be passive or active based on the addition of a fan which is typically used to increase air flow across the entire board or system. Heat sinks can have different aspect ratios. Types of heat sink Active Heat Sink. Where, T a is the approach fluid temperature to the device/heat-sink. Even better is the combination of heat extraction in winter with heat rejection in summer. A comparison of the interface between a heat sink and an IC without (left) and with (right) TIM. They're most commonly used in computers, but are also found in cell phones , DVD players and even refrigerators. Microchannel heat sinks function in a rather simple manner. It acts as a "bridge" for the southbridge chip to communicate with the CPU, RAM, and graphics controller. Heat sinks consist of fan or cooling device to disperse heat from another object. Alternatively referred to as the PAC (PCI/AGP Controller) and nb, the Northbridge is an integrated circuit responsible for communications between the CPU interface, AGP, and the memory.Unlike the southbridge, the northbridge is directly connected to these components. Heat sinks are either made up of aluminium or copper or any other material which is good conductor of heat. Heat source at the heat sink was obtained by placing the heater mat at the bottom of the heat sink with a regulated temperature of 60 °C using a thermostat and measurements was performed at ambient temperature of 27 oC and ambient humidity is 70% - 84%. 5. Understanding heat sink CFD simulations for greater clarity. In turn, the flow of undesired heat from that component would slow down and stop, and the basic function of the heat sink would be negated. In our experience, it generally estimates the overall heat sink volume within +/- … They absorb excess heat and then transfer it to another media like air or a liquid coolant. Heat sink CFD simulation results. E.g. We rst consider the case … The heat generated by the electronic component is transferred to the coolant by forced convection. The heat sink is usually made of aluminum or copper. Design considerations that omit this thermally conductive path can cause a device to become overheated, leading to premature failure or long-term reliability problems, such as the above-described experience. The simplest heat sink could consist of a single piece of thermally conductive metal. Multiple microchannels are machined on the back of the substrates of electronic components in integrated circuits. The heat sink size calculator is based on a well-established equation for estimating heat sink volume during the early stages of heat sink design. To dissipate, radiate and/or vent heat from some component which gets hot during use. A heat sink with high aspect ratio will have either-A greater density of fins in a specific footprint, The online model incorporates both fin efficiency and radiation functions. The heat produced can actually fry the processor and damage it. Placing a heat sink on a component won't be enough to properly connect the component to the heat sink. A heat sink is not just a reservoir for thermal losses. You'll need an adhesive method to create a solid thermal connection between the heating component and the heat sink. That’s due to the resistance the electricity gets while flowing through it. Adapted image used courtesy of TTS Group TIMs are heat conductive materials that can enhance the thermal coupling between the heat sink and the package. 2. EE World References The width of the heat sink is then calculated based on the number of fins required to dissipate the heat from the heat sink. Optimize your geometry for heat sink CFD simulations. Solar power fans that operate during the daytime are an easy way to accomplish this. It is not suitable for high profile heat sinks on account of the availability and fin efficiency. the processor will definitely get hot just by being turned on. Learn better about analytical functions like transient thermal FEA analysis. The storage function means that excess heat rejected during summer can be reused for heating in winter. Heat sinks are made of metals like copper or aluminum alloy. Heat Sink Attachment Methods. The heat sink is a heat trap storing vast amounts of thermal energy from the hot air in the greenhouse that would otherwise escape during the evening. When the heat sink utilizes fan (HSF) it is active heat sink. 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