It was easy to calculate the thermal resistance from the geometry of the. Radiation heat transfer can represent up to 30% of heat rate in natural convection heat sinks. A heat sink is an environment or object that absorbs and dissipates heat from another object using thermal contact either direct or radiant. In this report, both parts are considered separately. For the cooling purpose,it incorporates a fan or cooling device.
A heat sink was designed on geometry based optimization tool with the. Heat sinks are used in a wide range of applications wherever efficient heat dissipation is. When heat flows out of a transistor, it passes through the case transistor and into the heat sink, which then radiates the heat into the surrounding air. Pdf heat sinks are a kind of heat exchangers used for cooling the electronic devices due to the simplicity of fabrication, low cost, and reliability. Heat sink selection methodology advanced thermal solutions. Optimization of heat sinks with flow bypass using entropy. It also helps to clear up common misconceptions and design mistakes. Heat sink design goals may vary, but in this report, optimization of the vertical heat sink is the main objective. Heat transfer from the heat sink consists of radiation and convection from both the intrafin passages and the unshielded surfaces of two outer fins. At higher altitudes the convection contribution becomes less as the air becomes less dense ex. Reviewdesign and analysis of heat sink optimization and. The heat transfer in sinks is especially by convection, but also by radiation. To understand the principle of a heat sink, consider fouriers law of heat conduction. In earlier fabrications, a solid heat sink was either screwed or clamped to the power package.
And9016 heat sink selection guide for thermally enhanced. A heat sink is a passive heat exchanger that transfers the heat generated by an electronic or a. Mosfets, the minimum length of the heat sink in order to. Design considerations for thermal management of power supplies pdf. But the heat dissipation is still the major problem of enhancing the thermal performance the heat sink. Heatsink theory guide page 1 introduction heatsink theory guide page 2 materials.
A theoretical analysis of the cooling effect of a heat sink is presented in this study. Fouriers law of heat conduction states that if temperature. Pdf thermal analysis and optimum fin length of a heat sink. Thermal resistance theory and practice using a printed circuit board as a heat sink. The manufacturing process is usually by extrusion, but also by cast, bonded, folded, skived and stamped processes. The heat transfer theory helps explain practical aspects of how heat sinks work. Sometimes the transistor is connected to a large heat sink with fins causing more efficient removal of heat from the transistor.
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